Re: the problem of Oracle.exe

From: Vladimir M. Zakharychev <bob_at_dpsp-yes.com>
Date: Tue, 30 Apr 2002 13:48:04 +0400
Message-ID: <aalsm6$2sb$1_at_babylon.agtel.net>

This might indicate inapproriately high memory requirements in Oracle configuration which cause excessive paging. In Task Manager, there are two columns showing memory usage, one is Mem Size and other is VM Size, where Mem Size shows amount of physical memory currently consumed by a process, and VM Size shows amount of virtual memory dedicated to the process. (VM Size) - (Mem Size) gives amount of memory currently paged (written to disk). If this value is too high (like more than half of physical RAM) this means Windows is excessively paging Oracle process memory. To reduce memory consumption, tune your db_block_buffers

(which is buffer cache size in db_block_size's), shared_pool (which is
obviously shared pool size), java_pool_size (which is shared pool
size for Java VM processes),  log_buffer (which is redo log buffer size)

and large_pool_size (which is optional large object pool size). These values combined give you the minimum memory allocated for SGA (there's actually a bit more than that). Tune the SGA size to fit your available RAM minus 80 megs for OS needs and some 64 megs for PGAs and use LOCK_SGA parameter in init.ora to disable paging of SGA. So your ideal SGA should be around 350-380 megs and no more or performance will degrade due to paging when load increases.

Corrections and additions welcome.

-- 
Vladimir Zakharychev (bob_at_dpsp-yes.com)                http://www.dpsp-yes.com
Dynamic PSP(tm) - the first true RAD toolkit for Oracle-based internet applications.
All opinions are mine and do not necessarily go in line with those of my employer.


"IT" <john_cheng_at_impiric.com.hk> wrote in message news:aa7vlg$mfs$1_at_news.hk.linkage.net...


> Hi all,

> 

> My client is using Oracle 8i under Windows2000 server SP2. The hardware


> configuration is Compaq ProLiant ML370, PIII/866, 512MB RAM, 9GB HD * 2.

> 

> The problem is that after running a period of time (about 4-5 hours), the

> oracle.exe will use about 400MB of RAM. This makes the system very slow. My

> client needs to restart the server to release the RAM.

> 

> Does anyone know how to solve the problem?

> 

> Thanks!

> 

> 

Received on Tue Apr 30 2002 - 11:48:04 CEST