first time user with out of memory question

[Janning Vygen]

Am Sonntag, 11. Juni 2006 20:51 schrieb dormando:
> Janning Vygen wrote:
> > Hi
> >
> > i am running a dedicated memcached server with 4 GB Ram on linux (debian
> > stable) for php session data (kernel 2.6.8-2-k7-smp, memcached 1.1.12-1)
>
> Are you running debian-amd64 sarge or debian 32-bit sarge?
>

debian 32-bit sarge

kind regards,
janning

> > Two days ago i ran "out of memory". In the log it says
> >
> >    malloc(): Cannot allocate memory
> >
> > and stats slab produced "out of memory" message, too. At this time it was
> > impossible for many users to login to our web application.
> >
> > first i wondered because the "STAT bytes" was far lower than "STAT
> > limit_maxbytes". Then i read in the archives that memcached needs much
> > more memory than bytes to save. (60%). thats ok. i restarted memcached to
> > get it running again.
> >
> > but i am concerned about it. As i have 3,5 GB dedicated to memached (-m
> > 3584) it should not run out of memory.
> >
> > but anyway: i thought that memcached would delete the oldest key to get
> > space for a new key and you should never get an "out of memory" message
> > as i am NOT running it with -M (-M is not the default, isn't it?)
> >
> > but memcache is increasing memory since restart. Shouldn't it use old
> > entries before? I set expiration to 600 seconds but oldest entries are as
> > old as uptime:
> >
> > STAT items:8:number 38371
> > STAT items:8:age 87089
> > STAT uptime 87091
> >
> > Maybe i did something wrong with expiration time. But i set it to "time()
> > + 600".
> >
> > Is it possible that memcached hit an OS limit? a look at ulimit -a shows
> > me:
> >
> > core file size        (blocks, -c) 0
> > data seg size         (kbytes, -d) unlimited
> > file size             (blocks, -f) unlimited
> > max locked memory     (kbytes, -l) unlimited
> > max memory size       (kbytes, -m) unlimited
> > open files                    (-n) 1024
> > pipe size          (512 bytes, -p) 8
> > stack size            (kbytes, -s) 8192
> > cpu time             (seconds, -t) unlimited
> > max user processes            (-u) unlimited
> > virtual memory        (kbytes, -v) unlimited
> >
> > i guess i have to check this "open files" limit as this limits memcached
> > to 1024 connections, right?
> >
> > BTW: 'lsof | grep memcached' showed up some lines like this:
> >
> >   memcached 8487    root   10u  sock  0,4   54375193 can't identify
> > protocol
> >
> > what does it mean??? Is it ok?
> >
> > Ok, long post and i didn't got to a cool question which is easy to
> > answer. Maybe somebody can give me a hint anyway. Any help is very
> > appreciated.
> >
> > kind regards,
> > janning