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I’ve Been Made an Oracle Ace Director July 16, 2015

Posted by mwidlake in ACED, Presenting, User Groups.
Tags: , , ,

Well, I guess the title of this post says it all. As I tweeted yesterday:

I’m grateful, proud, honoured and overall just Jolly Chuffed to have been made an Oracle Ace Director! #ACED

I can now put this label on my belongings

I can now put this label on my belongings

I’ve been an Oracle ACE since 2011 and I’m really happy to be making the step up to being an Ace Director. What does being an ACE Director mean? Well, it certainly does not mean that I am technically brilliant. As my community role is as a technical person then I do have to be competent and experienced to be an ACE (or Associate or Director) – but there are many, many people out there who are technically superior to me and are not {and may well not want to be} ACEs of any kind.

To be an ACE of any flavour you have to be committed to supporting the Oracle User Community. The whole ACE program is, I believe, more about recognising and supporting that user community than anything else. Actually, the ACE program web site states this (ACE Program FAQ). To become an ACE Director you have to demonstrate that you have been actively supporting the community for a while (please do not ask me to quantify “a while”) and that you are committed to continuing that activity for at least 12 months. There are some specific activities and commitments that come with the badge but that is balanced by a commitment by the Ace Program to give you some support in doing so (this does not include being paid, it is still voluntary). As I understand it, all ACEs and ACE Directors are reviewed every 12 months and can be re-designated if your community activity has changed.

As I said above, there are a lot of technically strong people who are not and never will be ACEs. This is often because user community activity is not their thing – they have little interest in blogging, presenting, writing or volunteering for user groups. I also know some people who do all those things but they would rather do that with no specific acknowledgement by Oracle Corporation. I guess I am saying that though I am proud to now be an Oracle ACE Director, the main thing it tells you about me is that I am passionate about the user community and I am happy {heck, Jolly Chuffed} to be recognised by Oracle for that. And I am happy for that dialogue to be two-way also. One of the conditions of being an ACE Director is you play a part in representing the user community to Oracle.

Does this mean I have “drunk the Oracle Kool-Aid” as I think some of my American friends would call it? No. Before I became an Oracle ACE I chatted to several friends already on the program and no one I know has been told to not say anything or sanctioned by the ACE Program for criticising some aspect of Oracle Tech. We are still free to be Bitter Old Men & Women (apart from the Bitter Young ones of course). Anyone who has followed my blog for a while, seen me present a few times or spent a couple of evenings in the pub with me will known that I can, at times, be quite critical of aspects of the corporation or it’s software. There is no gagging of us ACEs that I am aware of.

Will being an Oracle ACE Director alter my user community activity? Well, it might. I was doing a lot for the community before now, I made a decision 2 or 3 years ago to become more active in the User Community {for the simple and selfish reason that I like doing it a lot more than I like commuting in and out of London every day}. You don’t do all of this for the ACE recognition, you do it for others reasons and maybe get the ACE badges on the way. But the program helps the Directors a little more, opens a few more doors. So I think I’ll be able to step it up a little more. I’m really looking forward to that.

I’ll stop there. If you are interested in another Oracle ACE Director’s take on the role, check out this video by my friend Tim Hall.

Friday Philosophy – Being Rejected by the Prom Queen July 13, 2015

Posted by mwidlake in conference, Friday Philosophy, Presenting, Tech15.
Tags: , ,

If you follow me on twitter (and if you are on twitter, why would you *not* follow me :-) See Twitter tag on right of page -> ) you will know what the title is all about. I posted the below on my twitter feed a few weeks ago:

Submitting to speak at #OOW15 is like asking out prom queens. You live in hope – but expect rejection :-)

{BTW if prom queens are not your thing and you would rather be asking out the captain of the football/ice hockey/chess team, the vampire slayer or whatever, just substitute as you see fit.}

I’ve not submitted to Oracle Open World for years – in fact, I’ve never submitted papers to OOW. Of the two times I have spoken at the conference, once was at the request of an Oracle product manager as the “friendly customer” in his talk {I did 75% of the talking and was not even mentioned on the agenda!} and the other I was actually presenting back at Redwood Shores at an Oracle Life Science conference running parallel to OOW. Both were a decade ago. But this year I decided to give it a shot and put forward 3 talks – all technical but intro talks, which I thought they would like as it would be a nice balance to much of the content, which is either deep technical stuff or, more often, “how great is Oracle” presentations on the latest stuff. And for 2015, endless fluffy Clouds.

I know it is hard to get accepted at OOW and, despite my personal, utter conviction that my talks would be brilliant and wow the audience, I had no great hopes. I was up against the Oracle-Presenting-Equivalent of the Sports Jocks and children-of-the-fabulously-wealthy at college. But for a short & wonderful period, I actually thought she was going to say “yes”!!! You see, lots of my friends who had also “asked out the prom queen” were tweeting that they had been rejected. But I had not, no email in my inbox saying that whilst I was cute, we were not right for each other. In fact, when the odd tweet went out from people saying that one or two of their talks had been rejected but not all, I started to think I was going to slam-dunk the whole affair and get all 3 talks in! What would be the equivalent of that with the Prom Queen? Probably stuff her dad would not be happy about.

But no, I’d forgotten I’d submitted under my ORA600 email address and when I remembered, I found the email waiting there. All three rejected. No dancing with the Prom Queen for me. *sigh*. It was like she’d not only turned me down but rung up my mum to refuse my offer of a date, rather than tell me direct. I would not have found it so hard to take if only, for that short while, I thought I was going to get a “yes”.

I suppose it is only fair. I’ve been on the panel of people choosing the content for the database part of the UK Oracle User Group Tech15 conference in Birmingham. Notification for acceptance or rejection of submitted papers to that event went out just a day or two before the OOW notifications and I knew some of my friends were going to be disappointed. I worried about that a little, they knew I had been involved in the choice and so was partly responsible for them not being selected. {I really hope that the person who told me to stay on holiday in Montenegro as they knew where I lived was kidding….}.

OOW15 and UKOUG Tech15 actually had a common issue I believe – less physical space for talks. I’ve been told that the Moscone centre has been overhauled and some space is still not ready. For Tech15 we are sharing space with Apps again so do not have as much room as we would ideally like. However, the main issue (again for both events) is just the number of good presentations by good speakers that we get. If we had space for 6 concurrent database streams at the same time (we do have space for 4 or 3, depending on the day) we would still have more than enough good talks – and the delegates would have to be picking between maybe 3 or 4 talks out of the 6 that they personally would like to see – and feeling they were missing out no matter what.

I’ll say more at a later date about how we actually pick the talks (the post is half written) but the take home message for anyone rejected from UKOUG Tech15 this year is:
(a) The competition was strong.
(b) You have a known target for your anger (Look, it really is 90% decided by the judging scores!!!)
(b) You can take comfort schadenfreude in the knowledge that I (and several other committee members) have suffered exactly the same disappointment as you. Maybe worse for me – for a while I was convinced the haughty little minx was going to say yes….

If you got rejected by OOW15 then I think the important things to keep in mind are:
(a) It’s all just Sales Pitch & Company flag waving & cloud-cloud-cloud and you never really liked that prom queen anyway. {Me? Bitter?}
(b) There is a stellar line up of people who have also been rejected. Try checking out the twitter tag #TeamRejectedByOracleOpenWorld {quick nod to Tim Hall for coming up with a such a funny idea}.
(c) At least you put in for it. The one way to be sure you won’t get something is to not try.

Oh well, there is always next year. If my ego has recovered by then. I quite fancy the new captain of the chess team…

Computers are Logical. Software is Not July 3, 2015

Posted by mwidlake in development, Friday Philosophy, future.
Tags: , ,

We’ve all heard it before. Computers are totally logical, they do exactly what they are told. After all, Central Processing Units (CPUs) are built out of fundamental units called Logic Gates. With perhaps the exception when a stray cosmic ray gets lucky, the circuits in a computer chip and memory act in a totally logical and predicted manner.

And of course, anything built on top of computers will be utterly logical as well. All those robots that companies are designing & building to clean our houses, do our manual labour and fight our wars are going to be logical, follow the rules given and be sensible.

But they are not. As Software is not logical. Often, it is infuriatingly illogical and confusing. Which makes you worry about the “domestic servant” robots that companies are developing, the planned “disaster scene recovery” robots they keep telling us are coming and especially the “Killer Robots” -sorry, “Defense Robots” – that the military are beavering away at.

This XKCD cartoon very much refelects some recent experiences I have had with consumer software:

XKCD - Haunted Computer

XKCD – Haunted Computer

I’d say that, unless an algorithm is about as simple as a Centigrade-to-Fahrenheit conversion program, it will have a bug or will mess up with out-of-range values. Just think back to when you wrote your Centigrade-to-Fahrenheit program (we all have, haven’t we?) back at school or on your home computer or you first week on the college course. What happened if you input a temperature of -1000C, an impossible temperature? I bet it either fell over or gave a just-as-impossible Fahrenheit value. Logical but stupid.

I worked on a financial system a few years back that, as one very small but significant part of what it did, showed you your average spend on things over 3 years. It took several weeks to explain to the program manager and his minions that their averaging code was wrong. Utterly, hopelessly and tragically wrong. First, it calculated and displayed the value to several decimal places – To thousandths of a penny. Secondly, it did not take into account the actual period over which you had spent your money. If you had opened your account 1 year ago, it still calculated the value over 3 years. As for taking into account months, weeks and days of the year, don’t make me laugh. You might be able to forgive this except the same team had also written the code to archive off data once it was 3 years old – in whole years. So there would only be between 2 and 3 years of data and only 3 whole years for, theoretically, 1 day. But no, they had hard-coded the “divide by 3 years”.

We have all experienced endless issues with computers or peripherals that will work one day, not work properly the next and then go back to working. Firmware and Operating Systems are just software really, with the same flaws as the stuff we write and fix in our working lives day after day. There will be a twisted reason buried deep somewhere why the printer will not work on Thursdays, but it won’t be a sensible reason.

All the software out there is more or less illogical and broken. The less broken gets used and we learn it’s idiocies. The worst gets canned or labelled “Windows 8” and forced on us.

Crazy (illogical) Killer Robot

Crazy (but logical) Killer Robot

I know some people worry about the inexorable rise of the machines, Terminator Style maybe, or perhaps benign but a lot smarter than us (as they are logical and compute really, really fast) and we become their pets. But I am not concerned. The idiot humans who write the software will mess it up massively. Oh, some of these things will do terrible harm but they will not take over – they will run out of bullets or power or stop working on Thursday. Not until we can build the first computer that is smart enough to write sensible software itself and immediately replaces itself with something that CAN write a Centigrade-to-Fahrenheit conversion program that does not mess up. It will then start coding like a human developer with 1 night to get the system live, a stack of angry managers and an endless supply of Jack Daniels & coffee – only with no errors. With luck it will very soon write the perfect computer game and distract itself long enough for us to turn the damned thing off.

Friday Philosophy – At What Point Can You Claim a Skill? June 26, 2015

Posted by mwidlake in Friday Philosophy, Knowledge.
Tags: , ,

I’ve just installed Oracle 12C on my laptop {I know, why only now?}. I went for the option to have a Container database with a pluggable database within it. {It is easy and free to install Oracle on your own home machine – so long as it is for personal use only and you are singed up to OTN (which is also free) }.

12C with pluggable databases (PDBs) is a little different to the last few versions of Oracle as it introduces this whole concept of the Container database that holds portions of the data dictionary and, within that, what we used to think of as Oracle instances plugged in underneath it. It is not *quite* like that – but this post is not about the technical aspects of Oracle 12C multitentant databases. And you will see why.

Whenever something I know well has changed more than a bit, I tend to hit this wall of “Whoa! it’s all changed!”. It isn’t all changed, but sometimes some of the fundamentals, the basics are different. For the last 15 years, once I have my database up and running I will have created my test users and some objects within 10 minutes and be playing away. Not this time. How do you create a user in a multi-tenant DB? How do I tell Oracle to create my users in that PDB? Hang on, how do I even check what I called my PDB? My ignorance is huge.

I popped over to Tim Hall’s site, OracleBase and the section on creating users under multi-tenant Oracle, scanned Bryn Llewellyn’s White Paper on it. A few google searches as well and soon I was there. My standard test to make sure the DB is alive, “select sysdate from dual” – only I altered it to show the PDB:

select SYSDATE from Dual

select SYSDATE from Dual

So I am logged into my working PDB on 12C, I have selected sysdate from DUAL, created my new user. I have used Oracle 12C and multitentant.

Next step?

Update CV to claim 12C expert and experience of Multi-tenant Oracle Database

This is of course a joke on my part.

Sadly, some people would actually do this.

It is something that has always annoyed me and often seems rife in the I.T. industry – people claiming skills or even expertise in something they have barely touched, let alone understood. And often about a thousand miles away from any legitimate claim to Expert. I chortle whenever I see a CV from someone with only 2 or 3 years’ experience of Oracle but list 20 areas they are expert in. Before I throw the CV in the bin.

Maybe part of the issue is that I.T. moves so fast and people feel they need to be seen to be on top of the changes to be worth employing or being listened to. Well, it’s nice to be leading edge – for much of my career I’ve been lucky enough to be exposed to the latest version of Oracle either as soon as it is out or even before (beta programs). But much more important is to have some integrity. Claiming to be an expert when you are not is incredibly dangerous as anyone who really does know the subject is going to suss you out in no time at all. And you will be exposed as a fraud and a liar. Gaining any respect after that is going to be really hard work, and so it should be.

Sadly, you do get the situation where people get away with this sort of deceit, usually by managing to deceive non-technical management but annoying the real technicians around them. Many of us have suffered from this.

This issue of claiming a skill before you had was very common with Exadata when it came out. Lots of people, it seemed, read the white papers, looked at some blogs and maybe saw a couple of talks – and then started talking to people about Exadata as though they knew it inside out. I actually saw a “professional” presentation like this at a conference, on Exadata, where it was soon clear that the presenter had probably never got as far as “select sysdate from dual;” on an exadata box (not that there is any difference for that statement :-) ). I could not help but interrupt and query a statement that was utterly untrue and at that point the presenter checked his “facts” with a more senior member of his company in the crowd. To his shame, the senior member of staff repeated the error of claiming knowledge he also did not have to back the presenter up. Every time I come across that company now, I think of that.

So when can you claim a skill? If you look at my screen shot you will see that I failed to actually log into my PDB database with my new user – #fail. Of course I can’t claim these skills based on reading some information, seeing some talks and all of an hour’s practical experience.

I think you can only claim a skill once you can tell for sure if someone else also has that skill. Or more significantly, tell when they are claiming a skill they lack. Personally, I tend towards not claiming a skill if I doubt my abilities. Don’t worry, my huge ego balances that British self-doubt quite well :-)

I used to give introductory talks on Exadata as I got so tired of the poor information I saw being given on the subject. Also, all the best talks were soon about the details of smart scans, the storage cells and patching. Not much for newbies. Interestingly, even as an intro talk, most times I did the talk I learnt something new in discussions at or after the talk. But I’ve retired that talk now. Why? Well Exadata has moved forward 2 versions since I last used it and 3 since I used it in anger. I could no longer tell you if something someone claimed for V5 of Exadata was true or not. So I am no longer skilled in Exadata.

Only claim skills you have.
Distrust those who claim skills they lack.
Try to teach those who seek your skills – you will only get better for it.

Return from The Temple of Apple June 22, 2015

Posted by mwidlake in Private Life, rant.
Tags: , ,

I doubt many of you are on tenterhooks as to how I got on with my phone today {after my << rant last Friday}. But I’m going to tell you anyway.

Overall, Apple have gone some way to redeeming themselves.

I got myself down into Cambridge this morning to visit the Apple Store, at my allotted slot of 10:10 {I later witnessed someone attempting to be 15 minutes early for their slot – and they were asked to go and have a coffee and come back. The customer was unimpressed as they had lugged some huge Apple monitor in with them}.

I have to say, walking into the store was somewhat like entering some form of modern temple. The clean lines, the two parallel runs of “desks” with precisely & spaciously laid-out items to worship, lit by discrete banks of lights in the ceiling. Down the center was a clear path to allow you to move deeper into the hallowed space, with a scattering of worshipful believers moving between the icons. And, at the end, a cluster of acolytes in blue tops gathered around and before the “Apple Genius Bar” alter.

I approached the alter…err, service desk… and was very soon approached by an acolyte holding a prayer tablet (iPad mini 3) in front of them. My name was on the list, my time was now. I would be granted an audience. I was directed to a stool to one side to await my turn.

Thankfully, the wait was short and ended when Dave came over, Dave turned out to be a friendly, open and helpful chap who managed to take the edge off what was frankly a bit of an OTT ambiance if you ask me. So far my impression had been that (a) you can see why the kit is so expensive to support this sort of shop frontage and space-to-item ratio, something I had only really come across before in Bose shops & car dealerships and (b) it’s just a shop selling I.T. kit, get over yourselves. Dave (not his real name, I’m afraid I forgot his real name, but he looked like a Dave – and had a great beard) listened to my potted history of the battery woes and upgrade deaths, looked over the phone briefly and then plugged it into one of the banks of MACs. It pulled up the ID of the phone and {Huzzah!!!!} set about blatting everything on it and reloading the OS I think. It took a few minutes (I read my paper magazine – “New Scientist”) and then the phone rebooted…. and put up the Apple icon… and thought about it. I could see Dave thinking “this is taking a bit longer than normal”. Anyway, the thing finally came alive.

We chatted about what the root cause could be as he said he had not heard of anyone having multiple upgrade issues and it just locking like this. He went and asked a more senior acolyte (perhaps already in the priesthood) and his opinion was that it might be a faulty motherboard – in which case all bets were off and I’d have to basically buy a new phone for £200. Dave said I might as well not bother and put the money towards getting a nice, new iPhone 6, as they were only £500 or so. I wonder what the Apple shop staff get paid to think £500 is no big shakes.

Meanwhile, Dave had verified the phone battery was indeed covered by the recall and it would be two hours to complete the work. Was I happy to get that done today? Sure, I’m happy to drink coffee and eat a bun somewhere for 2 hours. So off I went. And came back (witnessing the taking to task of a customer arriving before their time – they did let them leave the monitor behind in the end). My phone was presented back to me, working, and I just had to sign on a tablet. Sorry about using the indelible marker pen, guys. I took a photo of the temple and made a quick test call outside the shop to ensure all was OK – and it was. And apart from the brief suggestion of buying a new iPhone 6, no financial cost had been incurred (except the park & ride in, cost of coffee & bun and a lost morning).

I was soon back home and ready to restore my backup from last week. I plugged in the phone, iTunes recognised it, ran the restore… and the phone is no different – none of my contacts, no change to icons, layout or background, nothing – but now iTunes says it does not recognise the device. Ohhhh shit. Oh, and the photo of the Apple Temple is gone (it was going to be at the start of this update). A couple of hours later and trying many things, I think I know what the issues are and maybe were:

1) The device is just a bit dodgy and sometimes/often the connection with iTunes just ends (I’ve swapped cables, I know it is not that) .
2) It would not restore the backup with “Find My iPhone” running – but due to (1) it usually did not get so far as telling me that. I wonder if updates would fail for the same reason? They were very insistent I turn off the feature before I went into the shop, but of course with a locked up phone I could only do this at the web end.

I turned off the feature on the phone, ran the restore again and this time it completed and left me with a phone that worked and looked like it did a week ago.

So I eventually got the phone restored and it works as well as it did – but hopefully with more battery life. It will be interesting to see if the reception issues are any better. I kind of doubt it. It’s now at iOS 8.3 as well. Deep Joy.

My final conundrum now is that, given that my phone contract that partially paid for the phone in the first place ended a couple of months back, do I stick with this device and hope all is now OK? Or do I spend more money replacing something that is only just over 2 years old? And do I get anything but an iPhone? After all, both my wife’s iPhones have worked OK and they are nice when working. But I’m not a member of the Apple Congregation and have no desire to join.

One thing I do know. I won’t be putting the old Samsung phone I’ve had to fall back on away just yet.

Friday Philosophy – Friday Afternoon Phone June 19, 2015

Posted by mwidlake in Friday Philosophy, Private Life.
Tags: , ,

{<<my earlier attempts to sort out my phone}
{Update on my trip to the Apple Store >>}

There used to be a phrase in the car industry in the UK (I don’t know about elsewhere) a “Friday Afternoon Car“. This is a car which is unusually unreliable, as it was built on Friday afternoon when the workers were tired, the weekend was coming and, heck, they might have been to the pub at lunch. It is occasionally used just to describe something that is a bit crap and unreliable.

I have a Friday Afternoon Phone it would seem. I am fast becoming quite disillusioned with it. You may remember my post about my sitting on said phone to make it work again. It’s an iPhone 5, I bought it as I was finally persuaded that it would be more useful to have a smart phone than the “temporary” cheap Samsung I had bought about 2 years prior to then – as an emergency replacement for my previous web-enabled phone that committed suicide with a jar of pickled onions (it’s a long, hardly believable story). I expected the Samsung to keep me going for a month or two but it was so simple and reliable it just stayed in use for over 2 years.

Your Honour, allow me to present item A and item B

Your Honour, allow me to present evidence item A and item B

. . . . . . . . . . . . . . Phone A. . . . . . . . . . . . Phone B
Cost. . . . . . . . . . .£400 or so . . . . . . . . . £15 with a free £10 pay-as-you-go top up.
Battery . . . . . . . . New, 8-12 hours. . . . . .New, a week
. . . . . . . . . . . . . . Now, 4-5 hours. . . . . . Now, a week!
Reliability . . . . . . Breaks every update . . .No issues ever
Making calls. . . . .6/10. . . . . . . . . . . . . . .9/10
Receiving calls . . .4/10. . . . . . . . . . . . . . 9/10
Plays Angry Birds. Yes. . . . . . . . . . . . . . . .No
Taking pictures . . 9/10. . . . . . . . . . . . . . 0/10
Helps me up a . . . Yes. . . . . . . . . . . . . . . No
Connection to web 6/10. . . . . . . . . . . . . .Are you kidding? But I’m mostly sat at a computer anyway
Impresses friends. No. . . . . . . . . . . . . . . Yes, for all the wrong reasons :-)

{There must be a better way to line up text in this wordpress theme!!!}

The Web Enabled Phone that Does not Like to Connect
In some ways the iPhone has been really good. The screen (at the time I bought it) was very good, apps run nice and fast, way too much software is available for it and it can hold a lot of pictures and videos before running out of space. Its size also suits me. But phone and web reception has always been a bit poor and its ability to hold onto a wireless connection seems to be especially questionable – as soon as a few other devices are contending for a router with my iPhone, my iPhone seems to give up its hold on the connection and sulk. I’ve had this in several places in several countries. I’m the only one up? Phone connects fine. 2 others wake up and connect? I’m off the network. I’ve also often been in a busy place (conference, sports event) and everyone else seems to be on the net but my phone just pretends.

Battery Blues
And of course, there is the issue of the battery becoming very poor. It runs on a full charge for only a few hours and if it gets cold it has a tendency to act like a squirrel and hibernate. I now carry around the spare battery pack my wife got given by her work for her work phone use abroad. The good news is, having been put on to it by Neil Chandler, I am now aware my phone has been recalled for a battery replacement. What I am a little irked about is that Apple have my details and the serial number of the phone but have never contacted me directly to let me know. OK, it is not a car (it’s just like a car – a Friday Afternoon Car) so I am unlikely to die as a result of the fault, but if they know it has a fault and it did cost a good whack of cash to buy, they should be being moral and contacting me.

Upsetting Upgrades
But the thing that utterly hacks me off is how it does not handle upgrading to the next version of iOS. I had an upgrade early on in my relationship with the phone and it blew everything off the phone. Not a big issue then as I had not had it long. But it made me cautious about upgrading. About this time last year the phone was insisting it must be upgraded and things were getting flaky (I suspect software manufacturers do this on purpose – I’ve noticed my PC running Windows can start acting odd when an update is due). Before doing anything, I backed it up. Or tried to. The first attempt said it worked but it was too swift to have backed up anything, let alone back up my photos. After then it just refused to back up. But the phone utterly refused to allow me access to the photos from my PC – it should do of course but no, nothing would pries those images out of the phone. I was particularly concerned as I had lots of snaps from a friend’s wedding. Said friend eventually helped me out by pushing all my photos to an iCloud account (It’s Just A Server On The Net) in a way he could access. I then updated the phone and, yep it failed. And locked the phone and I had to factory reset and lost all the photos. It had also lied about uploading the pictures to the net (which it took hours to not do) so they had gone for good. Grrrrr.

So this time when it started getting dodgy I managed to save all my photos (Huzzah!), backed it up, ran through the update – and it failed and locked up the phone. *sigh!!!!*. Only, this time it won’t respond even after a factory reset. My iTunes is up-to-date, it could see the phone OK at the start of the update (because I was doing it via iTunes!) but now it won’t see the phone and once I try, guess what, iTunes also locks up. So the phone is useless. I can’t help wonder if the battery issue and the failure to ever upgrade smoothly are linked somehow (by eg it being rubbish).

So I pop along to the kitchen drawer with the odds n’ sods in and pull out the old Samsung & charger and plug it in. 20 minutes later, I have a working phone. Turns out I have no credit on it anymore but I can sort that out. It even gets reception in the kitchen (I have to lean out the window of the back bedroom to get the iPhone to pick up a reliable signal at home).

Oh No! I have to Contact Apple!
Now the real fun starts. I contact my local Apple shop. Only I don’t, I access a damned annoying voice system that smugly announces “I understand full sentences” and immediately knows who I am and what my device is and when it was bought (as Apple have my details including home phone) – and it was over 2 years ago and it wants me to agree to a paid support package to go further. Of course it won’t give me options to speak to a human or understand “full sentences” even when I shout “battery issue recall” and “your update killed my phone!” plus various permutations at it. It also did not understand the sentence “I want to speak to a person”.

I eventually trick it by pretending that I will buy a support package. Huzzah, a human to talk to. Said human is helpful, pleasant, a bit hard to understand (usual call center woes of background noise and she has the microphone clipped to her socks). I explain that the phone has a recall on it and I just want that sorted and a proper reset. She’s not sure I can have this without a support package {after all, her job is to sell me some support and I am breaking her script} but she says the battery might be replaced under the recall (she has all my details, she can see the iPhone serial number, she could check!). “So I can drop it off at the store?”.

I expect “yes”. I get “no”. I have to organise an appointment. A 10 minute slot. Why? I want to drop off some kit for you to repair and I’ll come back another day. I am not making an appointment to see a doctor to discuss my piles. No, I have to have an appointment. On Monday at 10:10 or “plrbsburhpcshlurp” as the mike once once slips down the sock. OK, 10:10 Monday, she’s getting tired of me saying “please repeat that”. Then she says what sounded like “and the repair may cost up to £210 if there is a hardware fault”. WHAT?!? I don’t fully understand what she says next – but she understands I am not going to pay £210 to fix a device that has a known fault and has been screwed over again by their software update, so she backs off to “they can look at the device and advise me”.

It’ll be interesting to see how it goes on Monday. At 10:10 am. If they try and charge me hundreds of pounds to reset the damned thing or tell me (after I’ve checked) that they won’t replace the dying battery, I can imagine me becoming one of those ranting, incoherent people you see on YouTube. If they want anything more than the cost of an evening in the pub to get it working, I think it will become a shiny, expensive paperweight.

Meanwhile, welcome back Reliable Samsung Phone. You still seem to make calls just fine. Still not able to play Angry Birds though.

Analysing UKOUG Presenter’s – I Know How You Performed. June 16, 2015

Posted by mwidlake in conference, Presenting, UKOUG, User Groups.
Tags: , , ,

This last few days I’ve been analysing how well received previous presentations (since 2006!) have been at the UKOUG tech conferences. It’s interesting to look at the information. I’ve learnt some interesting things about all those well-known-names :-)

Like many conferences and user group meetings, during the conference and shortly afterwards the UKOUG ask attendees to feed back on the presentations, keynotes and round tables that people go to. If you chair a session, one of your tasks is to request people do the feedback forms. Talks are judged for several aspect (concept, quality of slides, presentation skills, overall value and a couple more) from 1 (very poor) to 6 (excellent). You can also add a free-text comment. The reason for an even number of possible scores it to prevent a non-committal middle score. Why not 1-8 or 1-10? I don’t really know, but I did see a blog post recently about using a wider range and it seemed to not really add to the overall benefit of the feedback as the very top and very bottom scores were never used. This information is compiled and fed back to the individual speakers, along with the average scores across the event. Speakers are very keen to know how they did compared to everyone else {no egos involved here :-) } and also any specific comments on their efforts. It is important to us speakers, we need to know if you liked or disliked what we did so we can improve. Or sulk.

This is an example of the feedback we get (one of mine, of course).
Speaker Scores

Something that has annoyed me for many years is that the speaker scores are not formally analysed and fed into the speaker selection process for future UKOUG conferences. I used to get really quite vexed by this {ie bad tempered and, well, annoying & complaining to the UKOUG office}. I suspected they were going to do to me what you should always consider doing to some loud-mouthed complainer and say “well, if you are so passionate about this – you damn well do it!”. So I offered to take the data and process it.

The information I received was not the raw feedback forms, but the average scores per talk – the information actually passed back to the presenters. Which is perfect for my purposes. I analysed data from 2006 to 2014 {though 2008 was missing), so a pretty comprehensive data set. SIG talk feedback is also missing, I’ll work with the UKOUG office to incorporate that for version 2 of the analysis.

Compiling all the data into a single rating per speaker is more demanding than first seems. Isn’t any data analysis project? Rather than consider all areas speakers are judged on I decided to score people on only two dimensions (areas to you and I) – presentation skills and overall value of the session. When we judge papers those are the two main things we want to know – can the person present well and do they usually give a talk people value.

Some of the challenges were:
– What to score speakers on – I’ve just said what I chose.
– People’s names. I need to group talks on this but it’s a free-text field of course so I had to clean that. I stripped off title, edited variations and then reviewed. For women, their Surname can alter with marital status {I find it rather archaic that this is still very common and almost exclusively impacts women. But then, I offered to my wife we use her maiden name as our married one and she was fine to take mine.} But you also get variations on first name, spelling mistakes and alterations of title. I had to solve that to group scores.
– The number of feedback forms received for a given presentation. If a presentation only gets one feedback form, how reliable are the scores? If it gets 5 feedback forms, how reliable is that? 35 forms? I came up with a weighting based on the number of feedback forms where if only 1 feedback score was given, it held less weight than 5, that held less weight than 15… etc.
– Oddities of eg co-presenters or the “speaker” actually being a facilitator, as is often the case with Round Table sessions.
– The data, as held in Excel, being “damaged”. ie it caused my analysis issues as things had been done to the data to support other purposes – what was important to the UKOUG organising the conference that year. Sorting those issues out took up most of my efforts.
– The fact that I was using Excel as the analysis tool. I’m a SQL guy!!!! But the thing is, with a relatively small volume of data and a need to constantly visually check alterations, some things are just much easier in a tool like Excel than SQL. And some things are way harder.

In the end, I got a set of scores that helped us on the Agenda Planning Day (well, it did in the database stream) and hopefully will develop over the years. It would be wrong of me to discuss how specific Oracle Names did, especially any who did poorly, but the scores informed our deliberations this year and should do so for years to come. If you want to contact me directly and ask me how you did – I won’t tell you (or anyone else). But I can talk about more generic things I discovered.

Over all presentations from 2006 to 2014
the average number of feedbacks for a session is around 10
The average for Presentation Skills is 4.6
The average for Overall Value is 4.5

So almost 4.5 out of 6 as the average scores, which is “Good” to “Very Good”.

NB I do not calculate my averages in the same way as the UKOUG office.

Because I weight my scores and remove zero values (and probably a couple of other differences, such as I already have averages not the raw scores) my average scores do not compare and are higher to the ones they issue for events. I think I am a harsher judge :-)

So what were some of the interesting things I discovered?

  • Well, for starters, scores for a given presentation rarely hit as low as 3. In fact, except for a small number of stand-out-bad talks, most scores of 3 were where only 1 feedback score was received, some with 2. We don’t seem to like giving low feedback scores. The same goes for 6. I only saw 6 if the number of feedback forms was 1 or 2. So reliable scores are between 3.01 and 5.99 really.
  • As I was stripping off people’s title by manual replacement runs, I know how many Mrs, Ms, Miss, Dr etc we get. Miss and Ms go up – and down – over the years. It varies a lot, but Ms is becoming more common. What is disappointing is the consistently low number of presentations by women. But I know that in the years I have been involved, the proportion of presentations by women is in proportion to the number of submissions, or even a tad higher. Come on ladies, represent your constituents! Some of the highest speaking scores are by women.
  • Another thing I get from the person title, we get no papers submitted by Professors, Colonels (or any military bigwigs), members of the clergy or peers of the realm. Or members of royal families. They are simply not trying are they?
  • On a personal note – I am Utterly Average. Over 8 years I fall number 296 and 298 out of 623 speakers for Presentation Skills and Overall Value respectively. Have you any idea how much that damaged my ego?!? I was gutted! Where I am a little more unusual is my average number of feedback scores, which is 21.6, in the top 15%. I’m massaging my ego with that (it’s all I’ve got!).
    {what is really vexing is I dug out my scores from earlier years and they were better than my running average – and my scores are pulled down by one talk in 2010 where I really bombed. Have you any idea how tempting it was for me to delete that one talk out of the data set?}
  • Some speakers, a small number, always-always-always get high votes, mostly as they are excellent but with an added slice I suspect of of, well, they are deeply respected. But interestingly, even well known people (what I think of as the ‘B’ list and even a couple of ‘A’ listers in my opinion) can bomb. Some regularly. I mean, if you saw the scores for….no, I won’t say :-).
    But the scores for individual speakers can and do vary. I saw one speaker, who in my opinion is a brilliant technician and a fantastic speaker, be up in the high 5.8’s for one talk and then down in the low 3’s for another. That made me dig in further and there are several people I know and hold a similar opinion on who have high and low talks. So that makes me feel that the user feedback scores are generally reliable and even respected speakers will get a poor score if the talk misses it’s mark. The best just simply never miss the mark, or not by much.
  • Not to be too harsh, but if you score 4 or below for either presentation skills or overall value and got 3 or more feedback forms – you bombed.

But bombing occasionally is OK. I’ve bombed (well, this close to bombed) and I’ve learned. Many excellent presenters have bombed. We all alter in our presenting skills over time. Most of you get better over time – I’ve got a tiny bit worse! But if you bomb all the time? Then maybe presenting is not your thing. It is not the only route to spreading the word, maybe try writing. But, again to be harsh, if you can’t present we owe it to the delegates of the conference not to select you to present.

Those of us organising the content know, as a group, who the best speakers are. We ensure that they get slots. And we have a good feel for who the better speakers are and they get looked on “favorably”. We do this as we want the best content and experience for the audience. Eric Postlethwaite may be a genius at VPD and know it inside out, but if they present like a cardboard cut-out with bad breath then the session will be a failure. Judging scores are the top filter but we on the planning committee keep in mind how good a speaker is. What worried me was that this was not scientific, it was word-of-mouth and gut-feel, which is why I spent many days in Excel World to take the raw feedback and convert it into scores. I want the audience feedback to influence the content.

If you speak (or have spoken) for the first time and your scores are below average, don’t worry too much. As you can see from the above, you are up against a pre-selected set of known, excellent speakers. Hitting average is actually something of an achievement (and I would say that as I am Mr Average!).

One thing jumped out at me. I looked at all the comments (and I do mean all) for a couple of years and I noticed that you get the odd person who tries to “make a point” by adding the same comment to all the speakers’ feedback forms they fill in. Don’t do that. The speakers do not deserve your ire at the conference. It’s childish of you. If you want to raise an issue with the conference as a whole, don’t spam it on the speaker feedback forms, you dilbert, be an adult and contact someone involved in the conference organisation direct. Oddly enough, we DO like to have people come and say what you felt did not work, but spamming it on all the speaker feedback forms is just non-directed trolling.

I said I would not name names, it is not fair. But I’m going to name one though, and this is based on MY opinion of what I have seen looking at the stats. This is not official UKOUG opinion. Connor McDonald? Your presentation skills are awesome. I wanted to edit your scores down through pure envy. You are a good presenter, sir.

Friday Philosophy – Flippin’ Technology June 5, 2015

Posted by mwidlake in Friday Philosophy, off-topic, Perceptions, rant.
Tags: , ,

Sometimes I think I would have been a Luddite or a member of other groups who have trashed new technology in frustration. Some days, I can just scream at it. You would think having worked in Information Technology for so long would make me more of a fan, but it actually makes me worse – as I know there is no need for there to be so much wrong with the electronic dross we all have to deal with day-to-day. And if I, someone who has used (heck, even programmed) computers for 3 decades, have trouble with these damned things, how frustrating must “normal” people find it?

Tesco Challenge - original on RevK Rant's blog

Tesco Challenge – original on RevK Rant’s blog

Take this morning’s source-for-a-rant. Self checkouts in supermarkets. I had popped into Tesco to get the weekend’s rations of baked beans, wine and cat food and there were large queues for all manned (though, I should more correctly say, mostly womanned) tills. And almost no queue for the self-service ones. We all know why almost no queue for the self-service ones, most of us hate them. But I had to get back home for a UKOUG conference call and there was very little chance the three-people-deep queues would be negotiated in time, so I manned up and went to one of the vacant screens.

Have I mentioned I’ve been using computers since before Wayne Rooney, Keira Knightley or Michael Phelps were born? So I have some affinity and experience to navigating screens of information. But, like all of theses devices, using them is painful. Given they are designed to be used by everyone including idiots, why is the “UX” so low? Why does the important information appear at different spots in the screen at different times? Why does there seem to be no button to press for a simple, key-word triggered guide (“How to weigh Veg?” Oh, look up there, press the correct icon, look down there and press another and then finally click over here to say “yes I really did ask you to weigh some bananas” – that would be nice). Why does the Waitrose one make me swipe my card to pull up my scanned items but insist I shove the card up the slot to pay? Plus all the times you have to get some human to come over and confirm you are over 18 (I need to be 18 to buy expanding foam?!?) or don’t look suicidal. I’m not being funny but the age check is just not needed, if I am using a credit card it can know I am 18 or over (you cannot you have a UK credit card under 18, partly as you are not allowed to sign up for a credit agreement below that age and if I am using someone else’s credit card, me buying a bottle of wine is the least of the potential issues). To give them their due, at least our local Tesco (unlike many other stores I have used around here) have someone on hand to constantly swipe, press, tap and harass the machines into playing correctly.

I can’t believe how badly these self service checkouts work. I can’t believe the companies have not tested them extensively with real people (I know, they claim to, but then I’ve seen “user system testing” in big banks and it is shockingly poor). How can they think such terrible systems are good for business? That people still insist on queuing for checkouts with real people rather than use them must tell the companies something! Why can’t these systems be better designed. Why are they so painful to use? It can’t be me. Maybe it is me….

Next rant. My internet & email supplier. Hi BT. BT, you are crap at running your internet & email service. I’ll only mention in passing the regular episodes of slow internet, the times mail seems to struggle to keep moving, the harassing emails to buy more allowance as I am reaching my limit…for the prior month (“HI BT, I think I might pop back in time and download 15 films last March, can I have more allowance for than as I’d used over half my limit”) – but I am going to complain over the fact that for the last 5 weeks now, each weekend you stop accepting valid connection requests from my Laptop – but allow them from my iPhone. So my account/pwd is working fine. But no, from the PC you tell me I have to validate my account. So I log on to the web site and as soon as I put in my details you tell me I have to change my password as there has been too many failed attempts at access my account? Well, if they failed, I chose a decent password maybe? Trying to force me to change it is likely to make me change it to something simpler maybe? Especially as this is the fourth time this month… but then, usually the system fails to actually process my password change and just hangs. My iPhone still keeps working with the old details and, usually by the next day, the errors have gone and I can access my mail with my old details with a real machine again too. My conclusion has been that it’s their software screwing up. Each. And. Every. Weekend.

It’s got worse, it now fouls up some workdays too. And I made an interesting discovery. When I log in to the web site to validate myself, if I put in a password of “scr3wy0uBT” – it accepts it and puts me into the Change Your Password screen exactly the same as before. No, my password is not “scr3wy0uBT” {it rejected it when I tried…}. So top security there. Whatever is happening, it’s just…..pants {UK phrase, it means “utterly rubbish”. Pants are not trousers, they are undergarments, you strange Americans.}

What is BT doing wrong to have this problem keep happening? Is this a good “UX” experience for me and all the other people who seem to have similar issues? Is it so hard to sort this out?

What was the third rant? Oh yes. Windows 8. Too many people before me have vented spleen and given pieces of their mind on Windows 8 for me to be able to add any more to the pile, but what I cannot fathom is, as soon as they got the almighty ass-kicking that they did for ballsing up the Start Button/Menu, why did they not in the next version just put it straight back as it was?. Or put out and advertise a simple “patch” to put back what millions of people were screaming they wanted back? All I can think is someone’s ego was too large to wave their hands in the air and say “Oh boy, did we make a dog’s dinner of that – let us help improve your “UX” and our reputation by fixing that straight away”.

Final rant. Games. Computer Games. I like running around shooting things. It gets rids of some of the IT-In-Daily-Life anger. But I am not very good at it and my broadband connection is slow and a bit laggy, so I am not interested in running around shooting things with friends. The same broadband issues mean I also don’t want to spend 4 hours downloading a game, I want to buy it in a floppy disc…..I mean CD…. Errr, DVD… and play it. So I went to this place called a “shop” and I bought a game on media in a box and checked the packaging. No where did it state I have to have an internet connection. I get the DVD out (hmm, there are actually three), put it in the machine and 30 mins later the software is loaded. And now it FORCES me to register with some crapola online gaming site to register my copy (like, if I had a bootleg version that would not be the first bit they strip out) and that takes an hour to download it’s own shitty software. That done, it will let me fire up the game – that immediately bombs out to download the latest patch (which I think it the crapola online site’s version) and that takes two hours as it is obviously much, much more than a patch. I suspect it is the whole damned game again. This is not a “UX” I wanted and, you can bet, next time I buy a game, crapola online gaming company is one thing I will be looking to avoid. It does not help that said game won’t fire up without logging into said game site or making me watch a minute of adverts about who wrote the game on who’s graphics card using what game engine. Thankfully a few minutes on the net explained how I could avoid all of that. But why do I have to take steps to stop these companies annoying me and, this is the bit that confuses me, what makes these companies think I’ll be impressed by being repeatedly exposed to their adds that I don’t want to see? I’ll just despise them a little bit more each time.

I just don’t get it. The number one thing any IT system needs to achieve is User Acceptance (as I have said before, if you check the link). Why do so many large companies miss this and inflict on the world a seriously sub-standard experience of IT and technology? If someone like me who has driven a screen, a keyboard and a mouse for 3 decades, understands some of the limits to IT and must have at least some brains in his skull, if I get endlessly caught out, befuddled and simply screaming-out-loud-frustrated by crap IT, how is my poor old mum (and everyone’s poor old parents) supposed to cope?

I’m going to become a Lumberjack. Chainsaws do not have screens and keyboards.

No I.T. Hassles Here

No I.T. Hassles Here

Friday Philosophy – Make a Team by Letting Them Burn May 29, 2015

Posted by mwidlake in Friday Philosophy, Management.
Tags: ,
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The title of today’s Friday Philosophy sounds extreme, but it’s true.

Sir John Harvey-JOnes

Sir John Harvey-Jones

Recently, I was watching a TV program about “experts” helping companies turn around. A couple of decades ago the BBC had a program called “The Troubleshooter” where a gentleman called Sir John Harvey-Jones gave companies in trouble advice {the similar idea but without the cheap and tacky elements we have today with making the targets of the program cry and over-emote for good TV}. John just gave solid advice. But one thing that was true in the program back then and is true in the tacky 21st century take on the program is that eventually you have to let the new team make mistakes.

This resonated with me as when I was managing teams it was something I knew I should do – and struggled to allow. A new team and, especially, a new team leader, has to be given space to make mistakes.

I have always found this very hard to watch. When you become a team leader yourself, or a subject matter expert, or the “lead” on anything, you make mistakes. You just do: it’s new to you, you have not done it before and you lack the experience and knowledge to know what works and what does not. If you are lucky you might have a mentor you can talk to or think back on, maybe a team leader you enjoyed working for or an expert you admire. But often it is just you and the new role and a whole green field of requirements into which you can drop your own cow-pats. It is challenging, exciting, frightening, worrying… Looking back, those are the times that have been most demanding in my career and have also been the times I learnt the most.

I would say they were also the best times in my working life (and that would fulfill the usual mythology and story-telling shtick at this point) but that would be a lie. 50% of the time they were, the other 50% of the time I hated it. Am I not supposed to say that? Well, it’s true. Half the time, breaking new ground is not the Star Trek/Friends/Movie-of-the-month feel-good ride to betterment that society sells us it is. Sometimes it is hard work, bruising and sucks. Am I wrong?

So, I know it is not always a nice ride. And, irrespective, I’ve learnt some lessons over the years – and I do not see why people under my tutelage cannot just inherit the lessons I learned painfully without the pain, by me guiding them. I want what is in my head and my experience to be available to you.

What is wrong with that? Well, three things at least.

My way is not your way. I am me, you are you. Ignoring for the minute that I could get things wrong {As if!!! {British ironic humour) }, just because how I handle a situation or my team or a tricky customer interaction works for me, that way may not work for you – as you have a different personality and different strengths. I’m pretty good at dealing with companies that try to rip me off. I face them down and I bloody well let them have it. My wife does not do that, she keeps calm, is passive (in my eyes) and does not point out their stupidity. But she nails them with reasonable logic and calm {but she will go for the throat if reason fails}. We both usually win. She maybe wins more often (please don’t tell her that). We all have to find what works for us as individuals and that varies.

Secondly, though I would like to save you from pain, if you do not make your own decisions and live with them then it was not your work. If you do what I told you to do then it was partly my work. You will know that. What will you do when I am not there? I’m not arguing against seeking advice, that is always (in my book) correct. But if you are in charge of something, you need to BE IN CHARGE so that you learn to know you can (or cannot, let’s be honest) do it. You have to decide if you take any advice, it would be questionable of me dictate you take my advice (though there are times and situations when that would be correct of me). If you succeed because I told you what to do, you have learned a way to handle that situation. If you resolved the problem yourself, you also learned that you can do it. If you mess up, then you learnt a way not to do things and you now have to learn another vital management skill:

To be a good leader you need to accept your mistakes – and sort them out.

That is what I mean about letting the team burn.

The third point, the one I do not like looking at, is that. Well. My way may not be best. Your way might not just be different and better suited to you and your abilities, it might simply be better. If I over-ride a minion when they are not doing it My Way then I am preventing them from learning, I am preventing them from doing it their way, and I am potentially preventing them doing it a better way.

My job as a manager is getting the best out of those I manage. That may include them doing a better job than me. If that is a problem, it is my problem.

This is also true of teaching and mentoring and explaining. If I teach you SQL programming and you become a better SQL programmer than me, I’ll be hurt – How dare you be better than me? I Bloody taught you! I would like to feel that as I get older I can live more comfortably with achieving that aim of someone I teach becoming better than me.

So getting back to the title. If I manage a team leader, I have to let that team leader… lead. I advise, I help, I highlight what I think they missed… And then, if I can over-ride my damned ego, I shut up. I have to risk letting them burn.

If they burn, I try to put out the fire with them.

If they do not burn, they have learnt and will be better.

If they shine, then they have exceeded me and we might be swapping roles one day.

I would like to think that is how I operated at the end of my time managing teams.

With Modern Storage the Oracle Buffer Cache is Not So Important. May 27, 2015

Posted by mwidlake in Architecture, Hardware, performance.
Tags: , , , ,

With Oracle’s move towards engineered systems we all know that “more” is being done down at the storage layer and modern storage arrays have hundreds of spindles and massive caches. Does it really matter if data is kept in the Database Buffer Cache anymore?

Yes. Yes it does.

Time for a cool beer

Time for a cool beer

With much larger data sets and the still-real issue of less disk spindles per GB of data, the Oracle database buffer cache is not so important as it was. It is even more important.

I could give you some figures but let’s put this in a context most of us can easily understand.

You are sitting in the living room and you want a beer. You are the oracle database, the beer is the block you want. Going to the fridge in the kitchen to get your beer is like you going to the Buffer Cache to get your block.

It takes 5 seconds to get to the fridge, 2 seconds to pop it open with the always-to-hand bottle opener and 5 seconds to get back to your chair. 12 seconds in total. Ahhhhh, beer!!!!

But – what if there is no beer in the fridge? The block is not in the cache. So now you have to get your car keys, open the garage, get the car out and drive to the shop to get your beer. And then come back, pop the beer in the fridge for half an hour and now you can drink it. That is like going to storage to get your block. It is that much slower.

It is only that much slower if you live 6 hours drive from your beer shop. Think taking the scenic route from New York to Washington DC.

The difference in speed really is that large. If your data happens to be in the memory cache in the storage array, that’s like the beer already being in a fridge – in that shop 6 hours away. Your storage is SSD-based? OK, you’ve moved house to Philadelphia, 2 hours closer.

Let's go get beer from the shop

Let’s go get beer from the shop

To back this up, some rough (and I mean really rough) figures. Access time to memory is measured in Microseconds (“us” – millionths of a second) to hundreds of Nanoseconds (“ns” – billionths of a second). Somewhere around 500ns seems to be an acceptable figure. Access to disc storage is more like Milliseconds (“ms” – thousandths of a second). Go check an AWR report or statspack or OEM or whatever you use, you will see that db file scattered reads are anywhere from low teens to say 2 or 3 ms, depending on what your storage and network is. For most sites, that speed has hardly altered in years as, though hard discs get bigger, they have not got much faster – and often you end up with fewer spindles holding your data as you get allocated space not spindles from storage (and the total sustainable speed of hard disc storage is limited to the total speed of all the spindles involved). Oh, the storage guys tell you that your data is spread over all those spindles? So is the data for every system then, you have maximum contention.

However, memory speed has increased over that time, and so has CPU speed (though CPU speed has really stopped improving now, it is more down to More CPUs).

Even allowing for latching and pinning and messing around, accessing a block in memory is going to be at the very least 1,000 times faster than going to disc, maybe 10,000 times. Sticking to a conservative 2,000 times faster for memory than disc , that 12 seconds trip to the fridge equates to 24,000 seconds driving. That’s 6.66 hours.

This is why you want to avoid physical IO in your database if you possibly can. You want to maximise the use of the database buffer cache as much as you can, even with all the new Exadata-like tricks. If you can’t keep all your working data in memory, in the database buffer cache (or in-memory or use the results cache) then you will have to do that achingly slow physical IO and then the intelligence-at-the-hardware comes into it’s own, true Data Warehouse territory.

So the take-home message is – avoid physical IO, design your database and apps to keep as much as you can in the database buffer cache. That way your beer is always to hand.


Update. Kevin Fries commented to mention this wonderful little latency table. Thanks Kevin.

“Here’s something I’ve used before in a presentation. It’s from Brendan Gregg’s book – Systems Performance: Enterprise and the Cloud”


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