Re: PostgreSQL pre-fork speedup

Adrian Phillips <adrianp@broadpark.no>

From: Adrian Phillips <adrianp@broadpark.no>
To: pgsql-hackers@postgresql.org
Date: 2004-05-06T15:21:18Z
Lists: pgsql-hackers
>>>>> "sdv" == sdv mailer <sdvmailer@yahoo.com> writes:

    sdv> Yes, I realize it's a bit old but I just wanted to make a
    sdv> small point that forking is slower. It's funny you should ask
    sdv> because thread creation on Linux has in fact improved over
    sdv> process creation much more in 2.4 kernel.

    sdv> Benchmark at IBM shows Linux 2.4 thread creation is 30x
    sdv> faster than process creation. Process creation on Windows
    sdv> 2000 is about twice longer than process creation on
    sdv> Linux. This means forking on Win32 will be 2x slower! See
    sdv> 2002 benchmark below:

    sdv> http://www-106.ibm.com/developerworks/linux/library/l-rt7/?Open&t=grl,l=252,p=mgth

Excuse me for butting in here but this shows that fork AND exec is
slower than thread creation. I was under the impression that (for 2.2
or 2.4 at least) both fork and thread creation used clone (kernel not
libc). Only when a process does an exec does the diiference show
(well, actually it seems when either process modifies its stack).

Now, saying that, I have no idea how postgresql works so will shut up.

Sincerely,

Adrian Phillips

-- 
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