Re: is it cygwin or window2000 problem.?

Hi reini and yuzhouliu!

I get 62 connections with PostgreSQL 7.2 on cygwin + w2000.
Also stresstested it much like i described on
http://research.rem.nl/performance.html
No crashing during high load.

The limitation is due to windows not having a fork() call (yet), which
cygwin tries to overcome with a ProcessCreate32() (whatever) call, but that
one is bound to a max of 64 with the same name by windows, and one (or 2)
are taken by the masterprocess. So you get 63/62.
62 is the safe side.

If you want more connections use the new native PostgreSQL 8.0.1 for windows
(www.postgresql.org)
Or go to linux/bsd/unix for earlier versions.
Dont forget to set the buffersize according to the description in
postgresql.conf!

Greetings, J Hondius

-----Oorspronkelijk bericht-----
Van: pgsql-cygwin-owner(at)postgresql(dot)org
[mailto:pgsql-cygwin-owner(at)postgresql(dot)org] Namens Reini Urban
Verzonden: woensdag 16 februari 2005 9:53
Aan: yuzhouliu
CC: pgsql-cygwin(at)postgresql(dot)org
Onderwerp: Re: [CYGWIN] is it cygwin or window2000 problem.?

yuzhouliu schrieb:
> Reini Urban wrote:
>> yuzhouliu schrieb:
>>> hello:
>>> i install postgres in cygwin + windows2000NT,and it work good
>>> for
>>> myself.
>>> but more than 64 connections it will error to me:Could not fork
>>> new process for connection:Resource temporarily unavailable.
>>> why ? is it cygwin or window2000 problem.?
>>
>> That's a builtin cygwin limitation.
>>
>> But you are lucky that your system works with that many connections!
>> Recommended is to use much less. (5-15)
>>
> you say :That's a builtin cygwin limitation,
> what and how can i do.do i need to change my os to Linux or BSD,Unix?

no,
you may not use max-connections > 63 on cygwin.
Recommended is 10. I can do up to 40.

initdb tries the correct values automatically on init.
If this is wrong, because your system is too fast, you may want to set
this manually in /usr/share/postgresql/data/postgresql.conf and restart.
--
Reini Urban
http://xarch.tu-graz.ac.at/home/rurban/

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