High Memory Utilization

[Former Member]

Hi All,

If my system memory utilization hovers around 96%-99% (from Glance), is that normal? If it's not, how can I fine tune it? Currently using HP-UX B.11.23, Oracle 10.2.

Many Thanks!

[markus_doehr2 · Accepted solution]

It´s very difficult to tell if it´s "normal" since we don´t know, what you are runinng (R/3? ERP?), how many users, how your database is configured, if the sizing is correct, how big your buffers are configured...

Usually the operating system uses "unused" memory as filesystem cache so from this point of view it´s "normal" to see an almost full used memory.

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Markus

[Former Member · Accepted solution]

Hi Markus,

We are using ECC 6.0 with 8GB memory, concurrent users around 30-50 users. Data buffer and shared pool size is at 835,584 kb respectively. So base on your experience, you think it is normal for it to hovers around 96%-99%? It will reach to 100% utilization at time whereby it start paging out.

Thanks for sharing.

[markus_doehr2 · Accepted solution]

Our database server has always ~ 95 % - 98 % memory usage so I would say yes, it's ok. Do you encounter performance problems with that actual configuration?

To what value is your "filesystemio_options" Oracle paramter set?

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Markus

[Former Member · Accepted solution]

The filesystemio_options is SETALL. Your system using exactly OS and DB as mine? I don't think we have any performance issue so far but it's just that the memory consumption is too high and got us worried that we might run out of memory someday.

[markus_doehr2 · Accepted solution]

Not "exactly" the same configuration - but I just checked some other systems, they all "use" almost 100 % memory although "use" is not correct because many of them use it as filesystem cache, internal operating system buffers etc.

Just having a 98 % memory usage is not something to be afraid of, if 98 % of the memory was used by SAP or the database, THAT would be something to take care about.

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Markus

[Former Member · Accepted solution]

Thanks Markus, for being so helpful. 😃

[markus_doehr2 · Accepted solution]

What are the processes with the highest memory usage?

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Markus

[Former Member · Accepted solution]

Process Name with dw_sapR3P_D with owner name as R3PADM (SAP Admin ID). It usually take up around more than 200 MB per process.

[markus_doehr2 · Accepted solution]

Those are the workprocesses you see in SM50.

You can control the maximum memory usage of those using the profile parameters

abap/heap_area_dia

abap/heap_area_nondia

abap/heap_area_total

By default they are configured to 2.000.000.000 (2 GB).

How big is your Oracle SGA configured?

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Markus

[Former Member · Accepted solution]

My SGA Details as below:-

Database Buffers 855,638,016

Fixed Size 2,044,872

Redo Buffers 14,729,216

Variable Size 989,858,872

And the current size for the profile parameters you mentioned as below:-

abap/heap_area_dia 2000000000

abap/heap_area_nondia 2000000000

abap/heap_area_total 2000000000

[markus_doehr2 · Accepted solution]

Hi Jasmine,

I have found a note describing what you see:

Note 724140 - Extended memory, release for operating system

The memory is not released after it has been used but you can configure that using profile parameters.

Hope this makes things clearer.

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Markus

[former_member204746 · Accepted solution]

if using a JAVA stack, it may be using all memory left.

Is java stack installed?