Hana preload memory option

[dustin_self2]

When we originally converted to BW on HANA, I set some specific tables to automatically load to memory at database startup. Recently, though, I set the option for these tables to load NONE to memory on database startup. I even look in SYS.TABLES and see the column IS_PRELOAD as FALSE for these tables. But when we restart the database, these tables are still loading FULL to memory, even before any queries are ran. Any ideas?

Thanks,

Dustin

[Former Member · Accepted solution]

Hello Dustin,

HANA tries to reload previously loaded columns asynchronously and it is also based on previous load information for improved performance on system restart. I suppose there are no other tables which were used before previous restart significantly hence you see that these tables are loaded even though you have mentioned otherwise in table metadata.

BR,

Suhas

[lbreddemann · Accepted solution]

Correct Suhas.

SAP HANA comes with a PREload and a REload option.

The former needs to be set manually and happens during system startup before the instance is available. It prolongs the system startup but the tables are in memory from the beginning.

The second option (reload) is automatic and tries - after a system restart - to reload the columns to memory that had been loaded before the system went down or was shutdown.

- Lars

[dustin_self2 · Accepted solution]

Hello Lars,

Is it possible to turn off the RELOAD option for tables?

Thanks,

Dustin

[former_member209158 · Accepted solution]

Dustin,

The preload option is available per column and reload option which Lars pointed out is available for whole system. Its possible to turn off reload after restart using parameter reload_tables. Some information around it can be found in SAP Note 1889081.

Regards,
Abhishek

[dustin_self2 · Accepted solution]

Gotcha, thanks Abhishek!

Regards,

Dustin