Cool, Thanks, Shawn. I was also looking the swapiness and it is set to 60. Will try this out and let you know. Thanks, again.
On Thu, Feb 22, 2018 at 10:55 AM, Shawn Heisey <apa...@elyograg.org> wrote: > On 2/21/2018 7:58 PM, Susheel Kumar wrote: > >> Below output for prod machine based on the steps you described. Please >> take a look. The solr searches are returning fine and no issue with >> performance but since last 4 months swap space started going up. After >> restart, it comes down to zero and then few weeks, it utilization reaches >> to 40-50% and thus requires restart of solr process. >> > > I bet that if you run this command, it will show you a value of 60: > > cat /proc/sys/vm/swappiness > > This makes the OS very aggressive about using swap, even when there is > absolutely no need for it to do so. > > If you type the following series of commands, it should fix the problem > and prevent it from happening again until you reboot the system: > > echo "0" > /proc/sys/vm/swappiness > swapoff -a > swapon -a > > Note that when the swapoff command runs, it will force the OS to read all > the swapped data back into memory. It will take several minutes for this > to occur, because it must read nearly a gigabyte of data and figure out how > to put it back in memory. Both of the command outputs you included say that > there is over 20GB of free memory. So I do not anticipate the system > having problems from running these commands. It will slow the machine down > temporarily, though -- so only do it during a quiet time for your Solr > install. > > To make this setting survive a reboot, find the sysctl.conf file somewhere > in your /etc directory and add this line to it: > > vm.swappiness = 0 > > This setting does not completely disable swap. If the system finds itself > with real memory pressure and actually does NEED to use swap, it still will > ... it just won't swap anything out before it's actually required. > > I do not think the behavior you are seeing is actually causing problems, > based on your system load and CPU usage. But what I've shared should fix > it for you. > > Thanks, > Shawn > >
