Re: running out of file descriptors

[Bryan Christ <bryan.christ@gmail.com>]

Yes--the daemon runs as root.  It believe it's running out of file
descriptors because as soon as I hit that magic 700 number, the
daemons fail to stop accepting connections and all of the transfer
threads start aborting with EPIPE.  My only other thought is perhaps I
am somehow hitting a limit on the number of open sockets I can have...
but as far as I know that is the same as the number of max open file
descriptors.

On Mon, Feb 16, 2009 at 7:06 AM, Glynn Clements
<glynn@gclements.plus.com> wrote:
>
> Bryan Christ wrote:
>
>> >> I am writing a multi-threaded application which services hundreds of
>> >> remote connections for data transfer.  Several instances of this
>> >> program are run simultaneously.  The problem is that whenever the
>> >> total number of active user connections (cumulative total of all open
>> >> sockets tallied from all process instances) reaches about 700 the
>> >> system appears to run out of file descriptors.  I have tried raising
>> >> the open files limit via "ulimit -n" and by using the setrlimit()
>> >> facility.  Neither of these seem to help.  I am currently having to
>> >> limit the number of processes running on the system to 2 instances
>> >> allowing no more than 256 connections each.
>> >
>> > Have you tried editing /etc/security/limits.conf  (or equivalent file
>> > on your system) to increase the max number of open files?
>>
>> It seems that would be the same as setting RLIMIT_NOFILE via
>> setrlimt() or the same as using the userspace tool "ulimit -n".  Am I
>> wrong?  Isn't this the same?
>
> Is your daemon running as root? If not, it cannot increase any hard
> resource limit. Are you checking the return value (and errno) from
> setrlimit()?
>
> BTW, what do you mean by "appears to run out of file descriptors"?
> Which system call fails, and with what error?
>
> --
> Glynn Clements <glynn@gclements.plus.com>
>



-- 
Bryan
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