Any news on this (sorry if I missed it)?
Are both hosts solaris ?
The messages are single packets ? (Otherwise we'd check for
Nagle issue).
I see three timers in this order of magnitude.
By tuning each one individually with ndd we would try to get
a picture for which one influences the result.
tcp_push_timer_interval
tcp_local_dack_interval
tcp_co_timer_interval
But before that the snoop output may prove useful to look at.
-r
Jim M writes:
> Hello.
>
> One of the developers I support is having a performance challenge. He
> is writing a simple message processing application that receives a
> small message on a socket and writes a response to that socket, then
> waits for the next message. The application runs one thread per
> client connection. On a single-CPU system, a single application
> thread can process a message and transmit its response in under 1 ms.
> With two or more processors enabled, still running a single thread,
> there is a delay of about 40 ms between recipt of the message and
> transmission of the response. This delay is consistent, not
> intermittent. Running additional threads causes the delay to become
> inconsistent, but always in excess of 40 ms.
>
> We are running on a 900 MHz V880 with 4 processors under Solaris 9.
> Timing measurements were made with snoop.
>
> If anyone would care to suggest something we might do to get the
> latency down to a reasonable level on an SMP configuration, I would
> greatly appreciate it. Please let me know if you would find any
> additional information helpful.
>
>
> This message posted from opensolaris.org
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