Memcached Debuging/Server Logs Monitor the Memcached Servers?
I have chat engine which is based on the Memcached variables, putting them into arrays and reading them in other end via jquery,
which works fine 95% of the times, however when the server load is high memcached (presume its the memcached) the crash and browser gets stucks up.
I dont think its jquery issue since this only happens when the server load is very high.
I need a way to monitor the memcached servers or somehow write a log file into where the fails/errors comes in...
Any idea on how i can do this ? or any idea why memcached servers fails ? I run the memcached as follows
$GLOBALS['MemCached'] = FALSE;
$GLOBALS['MemCached'] = new Memcache;
$GLOBALS['MemCached']->pconnect('localhost', 11211);
My memcached config is as follows
#! /bin/sh
#
# chkconfig: - 55 45
# description: The memcached daemon is a network memory cache service.
# processname: memcached
# config: /etc/sysconfig/memcached
# pidfile: /var/run/memcached/memcached.pid
# Standard LSB functions
#. /lib/lsb/init-functions
# Source function library.
. /etc/init.d/functions
PORT=11211
USER=memcached
MAXCONN=1024
CACHESIZE=128
OPTIONS=""
if [ -f /etc/sysconfig/memcached ];then
. /etc/sysconfig/memcached
fi
# Check that networking is up.
. /etc/sysconfig/network
if [ "$NETWORKING" = "no" ]
then
exit 0
fi
RETVAL=0
prog="memcached"
pidfile=${PIDFILE-/var/run/memcached/memcached.pid}
lockfile=${LOCKFILE-/var/lock/subsys/memcached}
start () {
echo -n $"Starting $prog: "
# Ensure that /var/run/memcached has proper permissions
if [ "`stat -c %U /var/run/memcached`" != "$USER" ]; then
chown $USER /var/run/memcached
fi
daemon --pidfile ${pidfile} memcached -d -p $PORT -u $USER -m $CACHESIZE -c $MAXCONN -P ${pidfile} $OPTIONS
RETVAL=$?
echo
[ $RETVAL -eq 0 ] && touch ${lockfile}
}
stop () {
echo -n $"Stopping $prog: "
killproc -p ${pidfile} /usr/bin/memcached
RETVAL=$?
echo
if [ $RETVAL -eq 0 ] ; then
rm -f ${lockfile} ${pidfile}
fi
}
restart () {
stop
start
}
# See how we were called.
case "$1" in
start)
start
;;
stop)
stop
;;
status)
status -p ${pidfile} memcached
RETVAL=$?
;;
restart|reload|force-reload)
restart
;;
condrestart|try-restart)
[ -f ${lockfile} ] && restart || :
;;
*)
echo $"Usage: $0 {start|stop|status|restart|reload|force-reload|condrestart|try-restart}"
RETVAL=2
;;
esac
exit $RETVAL
Solution 1:
Define an additional variable in /etc/sysconfig/memcached
:
PORT="11211"
USER="memcached"
MAXCONN="1024"
CACHESIZE="64"
LOGFILE="/var/log/memcached.log"
OPTIONS=""
Edit the start()
function in the init script as belows:
start () {
#echo -n $"Starting $prog: "
# insure that /var/run/memcached has proper permissions
if [ "`stat -c %U /var/run/memcached`" != "$USER" ]; then
chown $USER /var/run/memcached
fi
#daemon --pidfile /var/run/memcached/memcached.pid memcached -d -p $PORT -u $USER -m $CACHESIZE -c $MAXCONN -P /var/run/memcached/memcached.pid $OPTIONS -vv > $LOGFILE 2>&1
$prog -d -p $PORT -u $USER -m $CACHESIZE -c $MAXCONN -P /var/run/memcached/memcached.pid $OPTIONS -vv > $LOGFILE 2>&1
RETVAL=$?
#echo
[ $RETVAL -eq 0 ] && action $"Starting $prog: " /bin/true && touch /var/lock/subsys/memcached
}
then restart the memcached, you'll see something like this in the /var/log/memcached.log
:
slab class 40: chunk size 616944 perslab 1
slab class 41: chunk size 771184 perslab 1
slab class 42: chunk size 1048576 perslab 1
<26 server listening (auto-negotiate)
<27 server listening (auto-negotiate)
<28 send buffer was 129024, now 268435456
<29 send buffer was 129024, now 268435456
<28 server listening (udp)
<29 server listening (udp)
Don't forget to configure logrotate.
Solution 2:
First, you are not showing memcached configuration, you are showing the startup script. You need to look for a file named like /etc/memcached.conf
. To enable logging, you need to uncomment the line
logfile /var/log/memcached.log
Also, you can increase the verbosity by enabling -v
or -vv
option.
If memcached is crashed, you can look into system logs /var/log/messages
and /var/log/syslog
to check for possible error conditions.