Swap usage with 16gb of RAM o.O
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Hello guys!
I have a Mac mini with 16gb of RAM installed, but I just noticed that the pfsense box is using 1% of the 32gb of Swap. Is this normal, is this a bug?
I will try to post as much info as I can below:
top -o size command output
last pid: 25917; load averages: 1.08, 0.91, 0.61 up 17+19:30:31 15:47:17 54 processes: 1 running, 53 sleeping CPU: 8.4% user, 0.0% nice, 6.4% system, 8.3% interrupt, 76.9% idle Mem: 1768M Active, 11G Inact, 2238M Wired, 185M Cache, 1843M Buf, 67M Free Swap: 32G Total, 298M Used, 32G Free PID USERNAME THR PRI NICE SIZE RES STATE C TIME WCPU COMMAND 76785 proxy 17 20 0 4710M 4216M uwait 1 27:03 54.98% squid 22577 root 15 20 0 1275M 1076M kqread 2 259:55 2.73% ntopng 30460 unbound 4 20 0 583M 507M kqread 0 535:03 0.00% unbound 22560 root 1 20 0 253M 23736K nanslp 1 26:51 0.00% php 14054 root 1 23 0 233M 26620K accept 2 0:00 0.98% php-fpm 246 root 1 24 0 229M 11524K kqread 3 1:13 0.00% php-fpm 76447 proxy 1 52 0 73644K 6804K wait 2 0:00 0.00% squid 45423 root 1 20 0 71040K 10964K select 3 7:53 0.00% bsnmpd 28114 root 1 20 0 65076K 4828K kqread 2 1:38 0.00% lighttpd 9459 root 1 20 0 56752K 7156K kqread 1 5:31 0.00% lighttpd_pfb 75081 root 1 20 0 55628K 5992K select 3 0:00 0.00% sshd 19663 root 1 52 0 43568K 1784K wait 3 0:00 0.00% login 7820 root 1 20 0 32424K 3780K select 0 0:00 0.00% sshd 87302 root 1 20 0 28344K 18104K select 3 2:49 0.00% ntpd 22985 root 1 20 0 28328K 2020K piperd 3 0:26 0.00% rrdtool 19298 root 3 37 0 28156K 4948K uwait 2 34:59 0.00% redis-server 37858 dhcpd 1 20 0 24844K 5284K select 1 2:20 0.00% dhcpd 15139 proxy 1 20 0 24080K 2924K select 2 0:21 0.00% pinger 75247 proxy 1 20 0 24080K 2920K select 2 0:19 0.00% pinger 63326 proxy 1 20 0 24080K 2920K select 0 0:15 0.00% pinger 53369 proxy 1 20 0 24080K 2920K select 3 0:06 0.00% pinger 5578 proxy 1 20 0 24080K 2540K select 3 0:28 0.00% pinger 77105 proxy 1 20 0 24080K 2528K select 3 0:27 0.00% pinger 83503 root 1 20 0 21988K 2976K CPU1 1 0:00 0.00% top 17674 root 1 20 0 21732K 4664K select 1 8:10 0.00% openvpn 53296 root 1 20 0 21160K 4228K select 1 4:56 0.00% miniupnpd 261 root 1 40 20 19024K 1980K kqread 0 0:00 0.00% check_reload_status 263 root 1 52 20 19024K 1748K kqread 3 0:00 0.00% check_reload_status 19584 root 1 20 0 18780K 1960K select 1 0:00 0.00% inetd 82779 root 1 44 0 17476K 3492K pause 2 0:00 0.00% tcsh 80773 root 1 52 0 17136K 2348K wait 2 0:00 0.00% sh 74340 root 1 25 0 17136K 2272K wait 2 0:05 0.00% sh 48779 root 1 52 20 17136K 1956K wait 3 3:53 0.00% sh 20417 root 1 29 0 17136K 1888K ttyin 2 0:00 0.00% sh 20168 root 1 52 0 17136K 1888K wait 0 0:00 0.00% shuname -a output
[2.2.6-RELEASE][admin@fserver.home]/root: uname -a FreeBSD fserver.home 10.1-RELEASE-p25 FreeBSD 10.1-RELEASE-p25 #0 c39b63e(releng/10.1)-dirty: Mon Dec 21 15:20:13 CST 2015 root@pfs22-amd64-builder:/usr/obj.RELENG_2_2.amd64/usr/pfSensesrc/src.RELENG_2_2/sys/pfSense_SMP.10 amd64General statistics
Services running
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Hello! Anyone has any ideas on what's going on? I have plenty of RAM available, so I'm not sure why the system is using my Swap one!
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The swap usage is quite low, I would not be worried about it.
Do you notice any performance hit?You can always disable swap, go to /etc/fstab and comment out or delete the swap mount line.
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The swap usage is quite low, I would not be worried about it.
Do you notice any performance hit?You can always disable swap, go to /etc/fstab and comment out or delete the swap mount line.
I didn't notice any performance hit to be honest, but it's quite intriguing why it's using swap when there's almost 80% free RAM!
thanks!
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I see squid running. I bet you had a memory spike once or more that caused some pages to get swapped out, but those pages have yet to be referenced again and just stay in limbo until the next time they are needed. Also, you don't need to reach 100% memory usage to get paging. Memory gets fragmented and if there are no large enough contiguous segments, the kernel may need to swap out pages to effectively defrag the memory.