[HBASE-11520] Simplify offheap cache config by removing the confusing "hbase.bucketcache.percentage.in.combinedcache"

• Type: Sub-task
• Status: Closed
• Priority: Major
• Resolution: Fixed
• Affects Version/s: 0.99.0
• Fix Version/s: 0.99.0
• Component/s: io
• Hadoop Flags: Reviewed

Release Note

Remove "hbase.bucketcache.percentage.in.combinedcache". Simplifies config of block cache. If you are using this config., after this patch goes in, it will be ignored. The L1 LruBlockCache will be whatever hfile.block.cache.size is set to and the L2 BucketCache will be whatever hbase.bucketcache.size is set to.

• Assignee: Michael Stack
• Reporter: Michael Stack
• Created: 15/Jul/14 20:42
• Updated: 06/Apr/18 17:51
• Resolved: 16/Jul/14 06:15

Description

Remove "hbase.bucketcache.percentage.in.combinedcache". It is unnecessary complication of block cache config. Let L1 config setup be as it is whether a L2 present or not, just set hfile.block.cache.size (not hbase.bucketcache.size * (1.0 - hbase.bucketcache.percentage.in.combinedcache)). For L2, let hbase.bucketcache.size be the actual size of the bucket cache, not hbase.bucketcache.size * hbase.bucketcache.percentage.in.combinedcache.

Attached patch removes the config. and updates docs. Adds tests to confirm configs are as expected whether a CombinedBlockCache deploy or a strict L1+L2 deploy.