Messages in this thread |  | | | Date | Sun, 23 Mar 2008 07:38:42 +0100 | | From | Manfred Spraul <> | | Subject | Re: Scalability requirements for sysv ipc |
Mike Galbraith wrote:
> On Sat, 2008-03-22 at 15:22 +0100, Manfred Spraul wrote:
>
>> Mike Galbraith wrote:
>>
>>> Total: 4691827 Total: 3942000
>>>
>>>
>> Thanks. Unfortunately the test was buggy, it bound the tasks to the
>> wrong cpu :-(
>> Could you run it again? Actually 1 cpu and 4 cpus are probably enough.
>>
>
> Sure. (ran as before, hopefully no transcription errors)
>
>
Thanks:
sysv sem:
- 2.6.22 had almost linear scaling (up to 4 cores).
- 2.6.24.3 scales to 2 cpus, then it collapses. with 4 cores, it's 75%
slower than 2.6.22.
sysv msg:
- neither 2.6.22 nor 2.6.24 scale very good. That's more or less
expected, the message queue code contains a few global statistic
counters (msg_hdrs, msg_bytes).
The cleanup of sysv is nice, but IMHO sysv sem should remain scalable -
and a gloal semaphore with IDR can't be as scalable as the RCU protected
array that was used before.
--
Manfred
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