Re: 8.1.7 on redhat 7.3 - not freeing memory

"Scott Dudley" <scott_at_nospam.telesoft.com> wrote in message news:3ECA519C.4080806_at_nospam.telesoft.com...
>
> we recently installed 8.1.7 on a dual processor, compaq proliant running
> redhat 7.3 with 4gb ram. one of our support staff asked me this morning
> why when oracle starts, does it quickly consume all available memory and
> then when shut down, does not free it. i've never observed this and
> suspect it has something to do with shared memory. can someone help me
> to address his question/concern?
>
> thanks.
>
> sample output from top:
>
> 8:53am up 16:40, 2 users, load average: 0.08, 0.07, 0.02
> 111 processes: 110 sleeping, 1 running, 0 zombie, 0 stopped
> CPU0 states: 0.0% user, 1.0% system, 0.0% nice, 98.0% idle
> CPU1 states: 0.0% user, 0.0% system, 0.0% nice, 100.0% idle
> CPU2 states: 0.0% user, 0.0% system, 0.0% nice, 100.0% idle
> CPU3 states: 0.0% user, 0.0% system, 0.0% nice, 100.0% idle
> Mem: 4387980K av, 4367712K used, 20268K free, 0K shrd, 197416K
> buff
> Swap: 2097096K av, 0K used, 2097096K free 3971020K
> cached
>
> PID USER PRI NI SIZE RSS SHARE STAT %CPU %MEM TIME COMMAND
> 15201 root 15 0 1072 1072 840 R 1.9 0.0 0:00 top
> 1 root 15 0 484 484 420 S 0.0 0.0 0:04 init
> 2 root 0K 0 0 0 0 SW 0.0 0.0 0:00
> migration_CPU0
> 3 root 0K 0 0 0 0 SW 0.0 0.0 0:00
> migration_CPU1
> 4 root 0K 0 0 0 0 SW 0.0 0.0 0:00
> migration_CPU2
> 5 root 0K 0 0 0 0 SW 0.0 0.0 0:00
> migration_CPU3
> 6 root 15 0 0 0 0 SW 0.0 0.0 0:00 keventd
> 7 root 34 19 0 0 0 SWN 0.0 0.0 0:00
> ksoftirqd_CPU0
> 8 root 34 19 0 0 0 SWN 0.0 0.0 0:00
> ksoftirqd_CPU1
> 9 root 34 19 0 0 0 SWN 0.0 0.0 0:00
> ksoftirqd_CPU2
> 10 root 34 19 0 0 0 SWN 0.0 0.0 0:00
> ksoftirqd_CPU3
> 11 root 15 0 0 0 0 SW 0.0 0.0 0:02 kswapd
> 12 root 25 0 0 0 0 SW 0.0 0.0 0:00 bdflush
> 13 root 15 0 0 0 0 SW 0.0 0.0 0:00 kupdated
> 14 root 25 0 0 0 0 SW 0.0 0.0 0:00 mdrecoveryd
> 22 root 15 0 0 0 0 SW 0.0 0.0 0:00 kjournald
> 101 root 18 0 0 0 0 SW 0.0 0.0 0:00 khubd
> 199 root 15 0 0 0 0 SW 0.0 0.0 0:00 kjournald
> 200 root 15 0 0 0 0 SW 0.0 0.0 0:00 kjournald
> 201 root 15 0 0 0 0 SW 0.0 0.0 0:01 kjournald
> 202 root 15 0 0 0 0 SW 0.0 0.0 0:00 kjournald
> 203 root 15 0 0 0 0 SW 0.0 0.0 0:00 kjournald
> 204 root 15 0 0 0 0 SW 0.0 0.0 0:00 kjournald
> 205 root 15 0 0 0 0 SW 0.0 0.0 0:01 kjournald
> 206 root 15 0 0 0 0 SW 0.0 0.0 0:03 kjournald
> 550 root 15 0 568 568 480 S 0.0 0.0 0:02 syslogd
> 555 root 15 0 440 440 380 S 0.0 0.0 0:00 klogd
> 599 root 17 0 0 0 0 SW 0.0 0.0 0:00 scsi_eh_0
> 616 ntp 15 0 1880 1880 1680 S 0.0 0.0 0:01 ntpd
> 634 root 15 0 4016 4016 2244 S 0.0 0.0 1:16 snmpd
> 650 root 15 0 4016 4016 2244 S 0.0 0.0 0:00 snmpd
> 651 root 15 0 4016 4016 2244 S 0.0 0.0 0:01 snmpd
> 654 root 16 0 1256 1256 1132 S 0.0 0.0 0:00 sshd
> 675 root 15 0 896 896 732 S 0.0 0.0 0:00 xinetd
> 723 oracle 15 0 5984 5984 5424 S 0.0 0.1 0:01 oracle
> 725 oracle 15 0 26632 26M 25584 S 0.0 0.6 0:01 oracle
> 727 oracle 15 0 5512 5512 4892 S 0.0 0.1 0:01 oracle
> 729 oracle 15 0 5684 5684 5060 S 0.0 0.1 0:04 oracle
> 731 oracle 15 0 22456 21M 21980 S 0.0 0.5 0:00 oracle
> 733 oracle 15 0 8240 8240 7788 S 0.0 0.1 0:00 oracle
> 735 oracle 15 0 16224 15M 15684 S 0.0 0.3 0:01 oracle
> 737 oracle 15 0 16880 16M 16336 S 0.0 0.3 0:01 oracle
> 739 oracle 15 0 16016 15M 15484 S 0.0 0.3 0:01 oracle
> 741 oracle 15 0 16044 15M 15516 S 0.0 0.3 0:01 oracle
> 759 oracle 16 0 3088 3088 2232 S 0.0 0.0 0:00 tnslsnr
>
> --
>
> Note: Remove nospam. from email address to respond.
>

SGA consumes the memory immediately on startup. On shutdown.... Linux, by nature, keeps as much as possible cached in RAM. So when you shut down, it doesn't "free" the RAM like other OSs display. As long as you are not going into SWAP, you are fine.

ken k Received on Tue May 20 2003 - 12:10:47 CDT