Hello,
I have few Solaris 11.2 servers. Since sometime, we are noticing high memory utilization in them.
Here is current config
root@ser22-zonemgr:~# /tmp/memory.sh
Physical memory size: 36864
Memory usage in MB: 32938
Memory usage in %: 89%
root@ser22-zonemgr:~#
root@ser22-zonemgr:~# echo ::memstat -v | mdb -k
Page Summary Pages Bytes %Tot
----------------- ---------------- ---------------- ----
Kernel 721833 5.5G 15%
Guest 0 0 0%
ZFS Metadata 74346 580.8M 2%
ZFS File Data 853646 6.5G 18%
Anon 2351933 17.9G 50%
Exec and libs 2369 18.5M 0%
Page cache 222555 1.6G 5%
Free (cachelist) 4922 38.4M 0%
Free (freelist) 486988 3.7G 10%
Total 4718592 36G
root@ser22-zonemgr:~#
From prstat -->
NPROC USERNAME SWAP RSS MEMORY TIME CPU
115 timesten 16G 15G 43% 76:49:22 1.6%
106 root 2887M 2698M 7.3% 383:50:51 2.2%
8 daemon 41M 56M 0.2% 1:15:31 0.0%
8 pkg5srv 37M 38M 0.1% 1:07:26 0.0%
8 john 12M 34M 0.1% 0:00:00 0.0%
2 smmsp 3936K 13M 0.0% 0:03:25 0.0%
2 netadm 3808K 9032K 0.0% 0:07:34 0.0%
2 netcfg 2560K 6664K 0.0% 0:07:39 0.0%
2 hspokes 2408K 15M 0.0% 0:00:00 0.0%
2 noaccess 2088K 8096K 0.0% 0:00:02 0.0%
And here is from another server
ser42-zonemgr:~# /tmp/memory.sh
Physical memory size: 16384
Memory usage in MB: 14653
Memory usage in %: 89%
ser42-zonemgr:~# echo ::memstat -v | mdb -k
Page Summary Pages Bytes %Tot
----------------- ---------------- ---------------- ----
Kernel 674735 5.1G 32%
Defdump prealloc 119423 932.9M 6%
ZFS Metadata 111996 874.9M 5%
ZFS File Data 168163 1.2G 8%
Anon 877423 6.6G 42%
Exec and libs 2496 19.5M 0%
Page cache 17788 138.9M 1%
Free (cachelist) 7 56k 0%
Free (freelist) 216864 1.6G 10%
Total 2097152 16G
ser42-zonemgr:~#
As I read few forums, I understood that the memory is filled with unmapped pages of data read from disk. It's kept in memory because those files may be read again and keeping the data in memory saves a disk read. That is where, OS is holding up memory. This is leaving less memory, which can be called as 'free'. Though whenever any application or DB needs that memory, OS will release. But our problem is, monitoring system. When total utilization hits 90% (right now it is 89%), it will page out SA.
What can be solution for this issue ?
Any recommendations ?
Thanks