the kernel to grab more memory for buffers in periods of intense I./O activity. If you have a very active database on ReiserFS or Ext3, Linux is
going to try to help you out by allocating more memory for the file system buffers, even by stealing pages from the active processes, which will, in turn. start paging. The only possible response is to eliminate the buffered I/ O and switch to non-buffered I/O. That is not so hard to do.
On 2003.11.01 09:44, Tanel Poder wrote:
Just for clarification, do you actually see swapping when starting a new process or you just guess linux would swap because you don't see "free" memory in top output?
Tanel.
----- Original Message ----- From: Sai Selvaganesan To: Multiple recipients of list ORACLE-L Sent: Saturday, November 01, 2003 1:34 AM Subject: RE: memory usage by dbw very high
rich
the ipcs output shows 1.1 gb. so nearly 2 gb(total ram size is 3.08) is
used by non shared memory size.
i went thru all the processes and found dbwr using the max %mem. what could
be the reason?
sai
"Jesse, Rich" <[EMAIL PROTECTED]> wrote: If I'm not mistaken, this figure includes the size of the shared memory segment from the SGA. Take the output of the "oracle" line of "ipcs -a" (hopefully you'll only have one!) and subtract it from the process size to get a better idea of the non-shared memory size of the process.
Rich
Rich Jesse System/Database Administrator [EMAIL PROTECTED] Quad/Tech Inc, Sussex, WI USA
-----Original Message----- Sent: Friday, October 31, 2003 3:49 PM To: Multiple recipients of list ORACLE-L
hi
i have a system that has no active users at this point of time. the memory used by the dbw process is very high leading to a lot of swapping when any process starts. here are the spces version:9.2.0.4 os:Linux 2.4.9-e.24smp o/p from top: 1:44pm up 29 days, 23:55, 4 users, load average: 1.73, 1.68, 1.35 132 proces! ses: 131 sleeping, 1 running, 0 zombie, 0 stopped CPU0 states: 24.4% user, 2.2% system, 0.0% nice, 72.2% idle CPU1 states: 0.5% user, 0.5% system, 0.0% nice, 98.0% idle CPU2 states: 0.0% user, 0.1% system, 0.0% nice, 99.4% idle CPU3 states: 0.3% user, 0.4% system, 0.0% nice, 98.3% idle Mem: 3089964K av, 3083380K used, 6584K free, 846848K shrd, 193448K buff Swap: 2048152K av, 1652K used, 2046500K free 1852468K cached sga size: Total System Global Area 1084823632 bytes Fixed Size 452688 bytes Variable Size 335544320 bytes Database Buffers 738197504 bytes Redo Buffers 10629120 bytes pga aggregate size:700M and ps o/p of dbw process USER PID %CPU %MEM VSZ RSS TTY STAT START TIME COMMAND oracle 4062 0.0 16.4 1131260 508168 ? S 10:16 0:06 ora_dbw0_revenue
please advise. what is really going on.
thanks sai -- Please see the official ORACLE-L FAQ: http://www.orafaq.net -- Author: Jesse, Rich INET: [EMAIL PROTECTED]
Fat City Network Services -- 858-538-5051 http://www.fatcity.com San Diego, California -- Mailing list and web hosting services --------------------------------------------------------------------- To REMOVE yourself from this mailing list, send an E-Mail message to: [EMAIL PROTECTED] (note EXACT spelling of 'ListGuru') and in the message BODY, include a line containing: UNSUB ORACLE-L (or the name of mailing list you want to be removed from). You may also send the HELP command for other information (like subscribing).
-- Mladen Gogala Oracle DBA -- Please see the official ORACLE-L FAQ: http://www.orafaq.net -- Author: Mladen Gogala INET: [EMAIL PROTECTED]
Fat City Network Services -- 858-538-5051 http://www.fatcity.com San Diego, California -- Mailing list and web hosting services --------------------------------------------------------------------- To REMOVE yourself from this mailing list, send an E-Mail message to: [EMAIL PROTECTED] (note EXACT spelling of 'ListGuru') and in the message BODY, include a line containing: UNSUB ORACLE-L (or the name of mailing list you want to be removed from). You may also send the HELP command for other information (like subscribing).