what is HANA system memory consumption?

[mrwong05]

For my Tenant DB, In Show Memory consumption view, system component is #1 usage, using 13 GB of 30 GB. For the SYSTEMDB System component also is #1 using 4 GB of 8GB. How can i reduce this usage? It seems to be growing more and more every week.

[former_member240094 · Accepted solution]

Hi Matthew,

First of all allocation limits of 30GB and 8GB seems less for a HANA system. Assuming this is your sandbox system with not much data, if you want to reduce memory consumption you will need to check what is consuming more memory on your system. Whether it is tables or any another heap allocators.

You can query on HANA statistics server tables to check on resource consumption. I would recommend you to go through SQL queries in attachment section of SAP note 1969700 - SQL Statement Collection for SAP HANA. You will find multiple memory related queries which you can run to find the consumption.

Thanks,

Arun Marria

[mrwong05 · Accepted solution]

Actually the total allocation for the hana system is 128 GB. Im saying that the used memory is 38 GB, 30 for Tenant DB and 8 for SYSTEMDB. For the Tenant DB, 13 GB is being used by unknown system. I am asking why this is growing and how i can stop it's growth. because when we installed the Hana, maybe <1 GB was allocated to System Memory.

I will check the SAP note, but dealing with the problem after it's found is the real reason I'm asking the question.

Many times SAP notes just say optimize the query with no instruction on how the queries are being processed (other than explain plans). I need to know if i should switch to another solution if HANA can't handle my query because of memory limitations.

[candy_zhan]

SYSTEMDB only use 4 GB memory? It's already small. You may have chance to reduce a little bit, reduce the retention of statistics data.

2529478 How-To: Configuring SAP HANA Statistics Server Parameters

For tenant, check if any big table size can be reduced.
2388483 How-To: Data Management for Technical Tables

Best regards,

Candy

[mrwong05]

Thanks Candy, I'll check statistics server, not sure what that is...yet

[mrwong05]

Hi Candy, My 256 GB server on SYSTEMDB is USED_MEMORY_SIZE = 30 GB COMPONENT=SYSTEM, What kinds of processes and tables are using memory with relation to COMPONENT = SYSTEM? I understand column and row table consumption, but SYSTEM is so general and I dont know how to reduce it's footprint.