[HBASE-11209] Increase the default value for hbase.hregion.memstore.block.multipler from 2 to 4

• Type: Brainstorming
• Status: Closed
• Priority: Major
• Resolution: Fixed
• Affects Version/s: 0.99.0, 0.98.2
• Fix Version/s: 0.99.0, 0.98.3
• Component/s: regionserver
• Hadoop Flags: Reviewed
• Assignee: Nicolas Liochon
• Reporter: Nicolas Liochon
• Created: 20/May/14 13:21
• Updated: 21/Feb/15 23:29
• Resolved: 23/May/14 17:46

Description

On a YCSB test, I saw a 33% performance increase, both on the max latency and on the throughput. I'm convinced enough that this value is better that I think it makes sense to change it on 0.98 as well.

More fundamentally, but outside of the scope of this patch, I think this parameter should be changed to something at the region server level: today, we have:

• global memstore check: if we're other 40%, we flush the biggest memstore
• local: no more than 2 (proposed: 4) memstore size per region.

But if we have enough memory and a spike on a region, there is no reason for not taking the write.