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Hi Jeroen, |
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on Saturday, 2006-04-22 at 22:26:43, you wrote: |
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> >Lacking any benchmarks from before the change, that's the best measure I |
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> >have. It might have been the firmware upgrade, but I doubt it. If I have |
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> >to reboot any time soon, maybe I'll do another test to verify it. |
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> > |
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> Rrright.. that's the big disadvantage of having to sort this stuff out |
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> on a production machine :) |
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> We're only now starting to convince (read: force) our developers *not |
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> *to put live code on production systems /before /we have had a chance to |
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> test it. |
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> You know how it goes... |
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Sure...actually I tested most of the installation on another machine |
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before switching it over to the server, but it didn't have quite the |
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same hardware. This is a fairly small university department so we just |
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can't justify a second ProLiant box for the occasional upgrade :) |
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> Still only 300mbits, though... a server like that should be able to |
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> handle SSH at near-line speed. |
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Yup...that one hasn't been faster before either though. |
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> >OK, that was a bit misleading, I meant that even assuming things about |
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> >the flat file the scheduler sees of the disk like that offsets in the |
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> >file sort of linearly correspond to cylinders |
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> That *may* be true for old IDE drives, but it isn't even remotely true |
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> for SCSI, which is its own higher-level abstraction on top of the |
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> physical drive interface already, |
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Huh? OK, block remapping for error recovery and stuff, but usually you |
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can observe in benchmarks how the transfer rate corresponds to the |
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offset, just like you'd expect it if the offset corresponded to the |
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cylinder. |
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> not to mention the layer the SmartArray puts on top of /that/. |
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Sure. That's why I was thinking of the NOOP scheduler. |
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> >---which is what it does to |
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> >implement things like the elevator algorithm---are virtually always |
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> >right for simple drives but may not be for a RAID. |
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> > |
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> Erm.. that's what I said :) |
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Me too :) Just haven't benchmarked NOOP yet but I'm gonna try. |
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Thanks for your input, I'll ask if we can afford the BBWC module...not |
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that anybody was crying for it, but an admin needs a new toy once in a |
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while as well! |
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cheers! |
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Matthias |
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-- |
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I prefer encrypted and signed messages. KeyID: FAC37665 |
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Fingerprint: 8C16 3F0A A6FC DF0D 19B0 8DEF 48D9 1700 FAC3 7665 |
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