Hana Database Not Starting due to Index Rebuilding

Case Study:

HANA DB Version : 96

Symptoms:

We are facing issues in ABC DB ,SAP HANA database not starting & System is currently down.

Then DBA Finding's :

Below Finding from Index Server Trace file:

If  Indexserver Having OOM & its showing  top allocators IndexRebuildAllocator  in the time of DB restart or not allowing to Start DB due to IndexRebuildAllocator  .Then follow as below.

Top allocators (ordered descending by exclusive_size_in_use).

1: Pool/IndexRebuildAllocator          79991234848b (74.49gb)

Whenever we perform database restart,  HANA triggers index rebuilding procedure of all the indexes at the same time. Rebuilding of each index requires a certain amount of memory which leads to OOM issue.

Solution / Work around:

 

We have added the following parameter which stops index rebuild in SAP Hana Database at the time of startup.

indexserver.ini

section:[row_engine]

parameter name: use_jobex_index_rebuild

parameter value:  false

Expected Fix: 

Once database is upgraded to version 97, we need to remove the above parameter.