*cough splutter*
Mar. 14th, 2005 09:02 pm![[personal profile]](https://www.dreamwidth.org/img/silk/identity/user.png){kind=small}
andrewduckerHaving arrived home to discover that, despite the best minds on the internet bending their minds in deep discussion to the solving of the problem, abortion is apparently still a contentious issue, I have decided to avoid getting involved in anything more than a desultory fashion (i.e. to point out that the problem depends on individual definitions of 'person' and is thus unlikely to be solved).
I am also feeling fairly ill, with a sore throat and spinning head. If I don't feel a fair bit better by tomorrow I shall stay at home rather than polluting the office - work's not in an emergency state at the moment, and I've got the bits of infrastructure in place to do with dates, so I don't need to push myself in if my brain is non-functional.
Am now going to stare vacantly at The West Wing (start of series 4) in the hope that I can keep myself occupied until tired enough to fall unconscious.
I am also feeling fairly ill, with a sore throat and spinning head. If I don't feel a fair bit better by tomorrow I shall stay at home rather than polluting the office - work's not in an emergency state at the moment, and I've got the bits of infrastructure in place to do with dates, so I don't need to push myself in if my brain is non-functional.
Am now going to stare vacantly at The West Wing (start of series 4) in the hope that I can keep myself occupied until tired enough to fall unconscious.
![[identity profile]](https://www.dreamwidth.org/img/silk/identity/openid.png){kind=small}
no subject
Date: 2005-03-14 10:00 pm (UTC)Where do you work?
no subject
Date: 2005-03-14 10:20 pm (UTC)no subject
Date: 2005-03-15 11:50 am (UTC)What do they code in COBOL for? Actually, what do they run?
(Curiosity....cats....I know)
no subject
Date: 2005-03-15 12:07 pm (UTC)We also run Assembler on the mainframe, and a variety of other bits and pieces of software, including DB2 for our relational databases and IMS for our heirarchical ones. If you don't know what a heirarchical database is then count yourself lucky :->
Off mainframe we use Java, VB6, C# and whatever other technologies are useful to us at the time.
no subject
Date: 2005-03-15 12:16 pm (UTC)Tens of millions of lines? Big project. Big fun ^_^.
no subject
Date: 2005-03-15 01:21 pm (UTC)Mainframes are largely different from PCs in their levels of redundancy - when you're processing billions of pounds of data through tens of millions of transactions in terabytes of data you _cannot_ crash. Everything is multiple redundany, backups happen over several levels (and are transparent - if I try to open a file that hasn't been looked at in a while then a message pops up asking me to wait and it's fetched from backup hard drives or from tapes (if it's been quite a while). Security is built in at the OS level and access to most files is on a line by line basis (it's possible to have access to append to a file but not read or modify it).
You wouldn't use a mainframe for your local business, but no bank or other large financical organisation would dream of working with anything smaller.
Oh, and heirarchical databases are a nightmare - you know how XML stores data for the 'children' of an item inside that item? Heirarchical databases are somewhat similar. Back when speeds were a lot lower they were the best way to store data that you always wanted access to together. Nowadays they just cause hassle :->
no subject
Date: 2005-03-15 01:31 pm (UTC)no subject
Date: 2005-03-15 02:02 pm (UTC)Why don't you try telling management that it would be better for your coding schemes to have a telnet/ssh link to the mainframe at all times, incase anything goes wrong. Of course, this would mean putting a nice box in your home, and you'd just *have* to *have* a Quad 3Ghz G5 / dual itanium / dual xeon / insert stupidly overpowered architecture here by the side of your bed to do that.....and a very, very fat pipe, of course.....
no subject
Date: 2005-03-15 02:35 pm (UTC)no subject
Date: 2005-03-15 01:58 pm (UTC)The closest thing I've come to that is when I assembled a 5Tb-holding 5U rackmount "Backup Solution" for my school (I was on work experience there in the summer). That had 3 hot swap PSUs, all the hard drives were hot-swap (and serial ata; guaranteed life of 7 years, cost a fortune, it held 20 of them) and were raided. I can certainly understand why the have systems like that (and will probably continue to have systems like that - look what happened when the US FAA 'Upgraded" *nix servers to Win 2K Advanced - they died after 48 days and there were 700 near misses) but still, yoiks.
How much space does the thing have? Petrabyes of stuff? If it just contains customer's financial information, then you must have a _lot_ of clients. How many processors does the thing have?
Oh, and I know that part of XML well....The library sold me a 2003 book on XML for £2 after someone wrote "Microsoft SUCKS" on the inside front page. I see why relational databases have replaced them (you have to admit, MySQL pwns)
no subject
Date: 2005-03-15 02:44 pm (UTC)And it uses Z/OS as its operating system - IBM mainframe people snigger at the youth and wish-washy-ness of Unix.
There's an old story about an IBM mainframe where, during maintenance, someone accidentally unplugged the main hard drive. The one that the swap file was on. The box carried on working, putting threads that depended on the memory on the swap file on hold, until someone noticed that lots of threads were waiting for resources, and plugged the hard drive back in. At which point it carried on as if nothing had happened. I'd like to see Unix do _that_.
Some more info here:
http://en.wikipedia.org/wiki/MVS
and here:
http://www.os390-mvs.freesurf.fr/mvs.htm
no subject
Date: 2005-03-15 03:14 pm (UTC)How much ram has it got?
And thanks for the links...wikipedia is like pringles- "Once you pop, you can't stop". I'm currently reading a page on how to mathematically invert a sphere. How I got to that from the MVS page.....
I see what you mean; the article makes them look more bulletproof than a challenger Mk 2. How large is it? And how many billions did it cost?
no subject
Date: 2005-03-15 04:06 pm (UTC)To be honest I don't think that they are that much faster (on a per-CPU) basis than a PC, or have that much more RAM, per se. What they have is amazing throughput, so that they can speed through data much faster than an indivudual PC can.
no subject
Date: 2005-03-15 04:13 pm (UTC)no subject
Date: 2005-03-15 05:09 pm (UTC)It's more, in fact, that we sometimes want to do a billing run which modifies vast numbers of customers, and does it all in a small time-period (like, overnight, when the databases can be opened exclusively).
no subject
Date: 2005-03-15 07:27 pm (UTC)....Does it play Quake 3 well? After all, that is *the* best excuse for most common benchmark in existence...
Yes, I do know that you *can't* play it on it, though if the BOHF is to be believed it doesn't stop professional sysadmins...
no subject
Date: 2005-03-15 07:38 pm (UTC)no subject
Date: 2005-03-15 07:58 pm (UTC)no subject
Date: 2005-03-15 10:31 pm (UTC)no subject
Date: 2005-03-15 08:43 am (UTC)no subject
Date: 2005-03-15 08:30 pm (UTC)