MEMORY I/O CONTENTION ON ORACLE 9I

[ashley75]

Jeff and Pando,

That's what I don't understand either. All I know is that when Linux doesn't start it take only 110M of RAM, after about one day, it goes up to 630M of ram and this is a new database, it has very few processes to it. and the memory never go down so that my database run really slow.
that's what I am confused and don't know what's going on.



[Edited by ashley75 on 07-29-2002 at 06:02 PM]

[pando]

and that's why I asked with what command are you using to determine that?

[ashley75]

Pando,

I used the TOP command

[pando]

well that's SHARED segment, it's not what Oracle is using, it is shared memory segments

[ashley75]

Pando,

so please tell me what I need to do???

the box does not have anything running on there beside Oracle

Below is the snapshot of what I am tlaking about


48 processes: 46 sleeping, 2 running, 0 zombie, 0 stopped
CPU states: 0.0% user, 0.1% system, 0.0% nice, 99.8% idle
Mem: 643708K av, 253288K used, 390420K free, 0K shrd, 44100K buff
Swap: 1518100K av, 0K used, 1518100K free 165240K cached

This is what happened after I bounce the databse an hour ago. and the amount of memory will increase from now till tomorow.

I am confused. please help me






[Edited by ashley75 on 07-29-2002 at 06:12 PM]

[pando]

nothing there is nothing needed to do, it's how it works and it does NOT mean Oracle is using that memory
It's how Linux works, it tries to cache everything in memory when it can

[ashley75]

Pando,

thanks again for all of the advise, but the database is not running as fast as I expect and the performance get worst if someone update something in the database. Below is the memory stats I got this morning:

CPU states: 0.0% user, 0.3% system, 0.0% nice, 99.6% idle
Mem: 643708K av, 564428K used, 79280K free, 0K shrd, 174416K buff
Swap: 1518100K av, 0K used, 1518100K free 223064K cached


Today, it goes up to 560M and noone have done anything to the database yet.

I am sorry to be annoyed but I like to understand what's going on with this box.

Thanks

[marist89]

Originally posted by ashley75

thanks again for all of the advise, but the database is not running as fast as I expect and the performance get worst if someone update something in the database. Below is the memory stats I got this morning:

Ah, now we come to the real problem. The database is slow, how do I tune it?

Find out where your bottlenecks are. Look at your disks, are they at 100%. What does your CPU say? What does vmstat say? Are only some queries slow? Which ones?

[srlhome00]

Have you checked the alert.log file? Do you see any ORA- message? There is a bug related to memory and process about Oracle 9i R2. You might need to apply patch if that is the causation of the server problem.

Susan

[ashley75]

Jeff,

Below is the stat of my system bottleneck:

null event 1 0 1 1
pmon timer 0 1 1
smon timer 0 1 1
rdbms ipc message 0 4 4

The CPU is idle or only being used a little not much.

I would say, not only certain query, seem like for all of query the users run.


srlhome00
Could you please refer me to the bug number as you mentioned???

thanks