On 14/02/2013 10:12 p.m., Amm wrote:
Hello,
I have a query about how --with-filedescriptors and ulimit.
Every 2-3 days I keep getting WARNING that system is running out of descriptors.
I compiled squid using --with-filedescriptors=16384.
So do I still need to set ulimit before starting squid?
Yes. Squid obeys both limits. The smaller of the two will determine how
many are available for active use.
Or does squid automatically set ulimit? (as it starts as root)
Squid can set its available FD state at something higher. Squid built
with system support for adjusting rlimit can use it to request higher
limits. But ulimit (or SELinux and friends) can come along later and
prevent a number of those sockets being opened...
I am using Fedora 16 with systemd squid.service (standard fedora file, no change)
Cache.log says:
2013/02/14 10:28:52 kid1| With 16384 file descriptors available
which is as expected.
squidclient gives this:
[root@localhost ]# squidclient -h 127.0.0.1 mgr:info |grep -i desc
File descriptor usage for squid:
Maximum number of file descriptors: 16384
Largest file desc currently in use: 888
Number of file desc currently in use: 774
Available number of file descriptors: 15610
Reserved number of file descriptors: 100
ulimit -H -n gives 4096
ulimit -n gives 1024
These are standard Fedora settings, I have not made any changes.
... when this proxy reaches the limit for Squid, you will get a message
about socket errors and FD reserved will jump from 100 to something just
below that limit to prevent running out of FD in future.
NP: there is a bug currently being investigated in squid-dev that Squid
does not report when it does not have rlimit support available.
So back to my question:
If I am compiling squid with --with-filedescriptors=16384
do I need to set ulimit before starting squid?
Or does squid automatically set ulimit?
Yes.
Amos
