Re: [K12OSN] cache running out of file descriptors (SOLVED)

[Mike Rambo <mrambo lsd k12 mi us>]

Eric Harrison wrote:
> 
> On Tue, 1 Apr 2003, Mike Rambo wrote:
> 
> >Yesterday I noticed "WARNING! Your cache is running out of file
> >descriptors" in cache.log.
> 
> I assume that means system file handles.
> 
> To adjust the maximum number of file handles, add the following line to
> /etc/sysctl.conf
> 
>         fs.file-max = 65536
> 
> and run "sysctrl -p"
> 

I assume this was 'sysctl -p'. I couldn't find a sysctrl on my system.

I tried this and somehow killed the server in the process. It acted like
something happened to iptables or something. We could ping the inside
netcard on the box from the WAN. From the box itself we could ping both
ways but no traffic was being forwarded anywhere. Nothing to squid and
no non-http traffic was being forward out either. We had to reboot the
box to get it running again. Since school was in session I was hesitant
to try it again so I held off. Later in the day I got some suggestions
from Henrik Nordstrom on the squid users list.

(among other things) Henrik Nordstrom wrote:
> 
> You can also try the following settings to reduce the amount of
> filedescriptors used:
> 
>   half_closed_clients off
> 
> And if that does not help
> 
>   server_persistent_connections off
> 
> and finally if still a problem
> 
>   client_persistent_connections off
> 

The first one didn't have any discernible effect. I tried the last two
this morning and have discovered it is a HUGE win. Not only have the
errors disappeared but access speed has increased very very noticeably.
According to cachemgr.cgi the number of requests per second we are
servicing has increased by fully one third. The difference in web
interactivity is amazing.

I'm still waiting for an answer from Henrik to see if there is any
downside to making these changes (the defaults were probably the way
they were for _some_ reason) but I wanted to send this experience back
to the list just in case it can help out someone else.

Thanks.


-- 
Mike Rambo
mrambo lsd k12 mi us