Re: [GENERAL] Hardware optimising - Mailing list pgsql-general

From Bruce Momjian
Subject Re: [GENERAL] Hardware optimising
Date
Msg-id 199909012321.TAA25838@candle.pha.pa.us
Whole thread Raw
In response to Re: [GENERAL] Hardware optimising  (Dimitri <dimitri@france.sun.com>)
List pgsql-general
> Hi Bruce!
>
> I think you are not right with remark about threads...
> At least with Sun Solaris you will be much faster with multithreaded
> process vs multi processes.
> Why? Because Solaris is real multithreaded kernel, so it sees only
> threads in the kernel level.
> "Process" is a user view for running task, and 1 process = at least 1
> thread.
> Why multithreaded process wil be faster than multi processes? - Because
> switching between threads will cost much less than between processes, so
> you wil have more CPU time to continue your job.
> And, of course, all threads can use any CPU, so you win more with more
> CPU(s), but even with ONE CPU on your machine you will be faster with 10
> threads than with 10 processes...

Agreed.  Sentenses removed.  New text:

We handle each user connection by creating a Unix process. Backend
processes share data buffers and locking information. With multiple
CPU's, multiple backends can easily run on different CPU's.<BR><BR>


--
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