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9:32:52
p_l
there are specialized banking DBs used for decades, often with data storage systems tailored for particular bank
9:33:24
p_l
Oracle, SAP HANA, etc. etc. shows up in analysis applications or various non-account parts
9:34:16
p_l
for example, in a project I work with, we use distributed in-memory store from Oracle (it was acquisition) for various "funds" data (it's called even "General Funds Manager")
9:34:42
beach
Despite what shka says, if I ever get the time, I should read up on all these issues and then form an opinion about the current state of things.
9:35:20
p_l
some of the most costly (in licensing and hw) systems are on the other hand low-memory (comparatively) but very highly available and more concerned with huge I/O rates as they talk all over the world
9:36:29
p_l
beach: generally, there's a lot of in-memory stores in play in OLAP, while many OLTP tasks are low-memory intensive but need disk for persistence and I/O for comms
9:36:49
p_l
meanwhile with OLAP it's all about "load as much data as you can so we can analyse it in all directions"
9:38:06
p_l
shka: well, yes, but I am not talking about lazy programmers who go with "what is easiest without considering drawbacks"
9:38:48
shka
what could be done and should be done is distributed, P2P, transactional, in-memory storage
9:47:10
shka
well, until big business will be able to swap developers in their lisp project, you won't see lisp projects in big business
10:26:58
p_l
shka: now consider that some of those machines require 2x the memory vs. what you can use, due to RAIM in mirror mode
10:27:25
p_l
phoe: "on the street" is the pricing without "enterprise markup" (actually an extra guarantee among other things, important when dealing with that kind of money)
10:28:38
p_l
and if you deal with things like z-series mainframes you have a machine that has 2.5 the amount of memory you can maximally spec, because mirror RAIM and that .5 for internal use by machine itself
10:31:10
p_l
I heard anecdotes of a big z-Series losing whole I/O drawer under max load and it having not affected the application
10:33:47
flip214
well, we've got a customer who didn't notice that his RAID controller was dead for two weeks, because the data was accessible via the software-mirror (DRBD)
10:35:23
p_l
flip214: this is more a case where the I/O of the system, which was under load (including things like mirroring to another machine) was unaffected
10:36:06
p_l
IO drawer is where things like Ethernet, Infiniband and FC (plus occassional ancient ESCOM) cards sti
10:37:31
p_l
reliable in-memory systems tend to be expensive as well, especially when you don't want to directly deal with disk (either huge expensive NUMA systems, or RDMA)
10:53:52
shka
p_l: RDMA is getting cheaper, and besides, even without RDMA you can build reasonable system
10:56:16
p_l
shka: yes, but the latencies make it very far from "let's just think of memory instead of multiple completely disparate systems"
10:57:00
p_l
and in my experience, companies balk when I suggest "ok, let me hit ebay, I'll have the 56GBit low-latency fabric ordered by tomorrow on the cheap" ;)
10:59:19
shka
anyway, those would be different beast, i agree, but this approach has some advantage over ultra expensive huge IO mainframes
10:59:56
p_l
most companies that lease mainframes have very specific reasons for doing so (combination of RAS requirements, power, software base, etc.)
11:01:05
flip214
you can get 56gbit IB, 2 dual-port adapters and 2 cables (so two machines can talk 112gbps) for < €1000
11:03:05
flip214
so all of the data needs to have been seen before the first data byte can be transmitted
11:04:25
p_l
shka: there are some low-level details that impact how fast you can go with Ethernet without changing it into non-Ethernet, including how it's designed for Store-and-Forward data
11:05:25
p_l
shka: IB doesn't have store-and-forward inside subnet (most sites anyone sees are single subnet)
11:08:17
p_l
Netherlands used Myrinet on mixed Myrinet/10GbE links, in poland I think we did something shitty with plain IP... ;)
11:08:45
p_l
flip214: IB uses IPv6 *addressing*, and intra-subnet packets have 16bit address for wormhole routing
11:09:32
p_l
the 16bit addresses are internal affair of the subnet that software stack is not supposed to bother itself with (outside of management software for subnet itself)
11:11:54
p_l
it's much harder to do wormhole switching when you have to match complex 128bit addressing to ports ;)
19:27:33
rpg
I suspect that CL-DOT cannot handle subgraphs, but I'm not 100% sure. Can anyone confirm?
21:29:51
fiddlerwoaroof
When I quickload it in Lispworks, I get an error about defining (METHOD DESCRIBE-OBJECT :AFTER (SYMBOL T)) visible from package Common-Lisp
21:31:13
fiddlerwoaroof
I guess this settles it: "Users can write methods for describe-object for _their own_ classes if they do not wish to inherit an implementation-supplied method."