Cache_size parameter changes

[Former Member]

Hello,

For a MaxDB system, the cache_size parameter was changed depending upon the hardware. Later, the hardware was moved to a small box due to a db crash and then we have observed that the parameter got changed to a new value.

As far as the time stamp show, it got changed during the DB restart.

Please let me know if the MaxDB system automatically changes the parameter.

Thanks a lot in advance!

Regards,

Ankit

[thorsten_zielke]

Hi,

in general, the CacheMemorySize (or CACHE_SIZE in older releases) value does not change automatically except if:

1. the installed server memory size falls below the configured CacheMemorySize.

2. a MaxDB is installed (without importing the parameters from a backup) and no user interaction done to overwrite the calculated default value based on the servers memory configuration.

Thorsten

[former_member188883]

Hi Ankit,

Cache_size in MaxDB is dynamic and it depends on installation and hardware configure.

There is some calculation defined for cache_size as per wiki link

http://wiki.scn.sap.com/wiki/display/MaxDB/MaxDB+Memory+Sizing?original_fqdn=wiki.sdn.sap.com

Hope this helps.

Regards,

Deepak Kori

[Former Member]

Hello Deepak,

Thanks a lot for your reply.

Also the link is very helpful indeed.

Kindly let me know if you have any further documentation regarding this parameter.

Thanks and Regards,

Ankit

[former_member188883]

Hi Ankit,

Additional information can be found it below SAP note

1128916 - FAQ: SAP MaxDB/liveCache heap management

Hope this helps.

Regards,

Deepak Kori