Toothed Belt Warning Light Immediate Overheat
05-09-2009 | 04:16 PM
#61
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multitasking is a process where individual subprocesses receive some tiny fraction of the total attention actually required for all the tasks included. Formula is something like the inverse-square rule as it applies to any two tasks attempted concurrently. Obviouly more than two at a time is exponentially worse.
Give me a second to get linsh gooing and I'll expound more fully...
Give me a second to get linsh gooing and I'll expound more fully...
You've completely neglected queue priority and thread-dependent vs thread-independent functions. Also, the IO scheduler plays a role in task queing. Know your semaphores, they will guide you(Solaris is the master at this).
05-09-2009 | 06:26 PM
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From: Gone. On the Open Road
05-09-2009 | 07:11 PM
#63
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Hey, I said Solaris, that's sys V, rel 4 from SunOS 4 right through S-9. Cha-ching
IIRC, the latency was first a result of flushing dirty cache, then the pages got a freshness bit and a lot of that latency went away cause they could overwrite. Been a while, I don't recall exactly. I never coded for Sun, just fixed em.
05-09-2009 | 07:53 PM
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Hey, I said Solaris, that's sys V, rel 4 from SunOS 4 right through S-9. Cha-ching
05-09-2009 | 08:16 PM
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I haven't paid attention to R-T issues, since Sun0S 4. But, IIRC, that was still BSD-based. IRIX (SGI's spin of Sys V with R-T extensions, specifically for interrupt latency) was, at the time, the only reasonably-pure UNIX workstation OS on which you could do "real" real-time stuff.
NREL could model weather for all of N america, it was - impressive.
Manly computing.
Last edited by docmirror; 05-09-2009 at 08:36 PM.
05-09-2009 | 08:24 PM
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Yup. Drool. In the mid-80s, SGI brought in some workstations to demo for us. The company I was at, at the time, bought a boat load of 'em.
There was one project I worked on for which we needed certain bitmaps. We added a nice "splat" sound when these certain bitmaps appeared on the displayed world map. The Navy brass was not amused. At all.
Manly computing.
