Re: Too many open files (was Re: spinlock problems reported earlier) - Mailing list pgsql-hackers

From The Hermit Hacker
Subject Re: Too many open files (was Re: spinlock problems reported earlier)
Date
Msg-id Pine.BSF.4.21.0008272025160.717-100000@thelab.hub.org
Whole thread Raw
In response to Too many open files (was Re: spinlock problems reported earlier)  (Tom Lane <tgl@sss.pgh.pa.us>)
Responses Re: Too many open files (was Re: spinlock problems reported earlier)
List pgsql-hackers
On Sun, 27 Aug 2000, Tom Lane wrote:

> Hmm, this is interesting: on HPUX, man sysconf(2) says that
> sysconf(_SC_OPEN_MAX) returns the max number of open files per process
> --- which is what fd.c assumes it means.  But I see that on your FreeBSD
> box, the sysconf man page defines it as
> 
>      _SC_OPEN_MAX
>              The maximum number of open files per user id.
> 
> which suggests that *on that platform* we need to divide by MAXBACKENDS.
> Does anyone know of a more portable way to determine the appropriate
> number of open files per backend?

Okay, I just checked out Solaris 8/x86, and it confirms what HP/ux thinks:
    _SC_OPEN_MAX            OPEN_MAX                   Max open files per
       process
 

I'm curious as to whether FreeBSD is the only one that doesn't follow this
"convention"?   I'm CCng in the FreeBSD Hackers mailing list to see if
someone there might be able to shed some light on this ... my first
thought, personally, would be to throw in some sort of:

#ifdef __FreeBSD__ max_files_per_backend = sysconf(_SC_OPEN_MAX) / num_of_backends;
#else max_files_per_backend = sysconf(_SC_OPEN_MAX);
#endif




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