Solaris 10 and Oracle 10g - swap space problem
Date: Tue, 28 Jul 2009 19:31:16 -0400
On Solaris 10, when I start my databases, I see my swap space usage increase in a one for one ratio with memory utilization. System has 64gb of memory. If I start up a 4gb database, I see 4gb of real memory used and 4gb of swap space used up as well (as shown by top, swap -l, swap -s etc.). This is purely a Oracle database server, and /etc/system and projects / resource controls seem to be set up, so I do not understand why swap is being touched. If I stop all oracle processes, swap drops down to about 100 Mb used.
I have taken great pains to make sure that NO swap is being used, yet any little allocation of Oracle gets tossed into swap. I don't know where to look after this- I would have suspected /etc/system or resource control / projects to be at fault, or /etc/security (ulimits) but everything looks ok. The system has 64g real, and about 54 gb swapif I get close to 54gb memory allocated oracle will return out of memory errors.. Needless to say the system crawls.
What am I overlooking ? TOP and swap -s / swap -l agree so its not a TOP anomaly
Example from TOP - I have 20g free, so why so much used in swap ?
load averages: 0.64, 0.57, 0.46
1073 processes:1071 sleeping, 2 on cpu
CPU states: 98.3% idle, 1.2% user, 0.5% kernel, 0.0% iowait, 0.0% swap
Memory: 64G real, 20G free, 40G swap in use, 17G swap free
PID USERNAME LWP PRI NICE SIZE RES STATE TIME CPU COMMAND 1997 oracle 1 39 0 4376K 2592K cpu/50 0:02 0.04% top
3454 oracle 1 52 0 16G 16G cpu/32 0:00 0.03% oracle
3456 oracle 1 24 0 16G 16G sleep 0:00 0.03% oracle
18589 oracle 1 59 0 16G 16G sleep 0:13 0.02% oracle
total: 39170184k bytes allocated + 2262264k reserved = 41432448k used, 18017608k availableReceived on Tue Jul 28 2009 - 18:31:16 CDT