[HBASE-5569] Do not collect deleted KVs when they are still in use by a scanner.

• Type: Bug
• Status: Closed
• Priority: Major
• Resolution: Fixed
• Fix Version/s: 0.94.0, 0.95.0
• Hadoop Flags: Reviewed
• Assignee: Lars Hofhansl
• Reporter: Lars Hofhansl
• Created: 13/Mar/12 04:40
• Updated: 26/Feb/13 08:12
• Resolved: 21/Mar/12 00:01

Description

I noticed this because TestAtomicOperation.testMultiRowMutationMultiThreads fails rarely.
The solution is similar to HBASE-2856, where expired KVs are not collected when in use by a scanner.

—
What I pieced together so far is that it is the scanning side that has problems sometimes.

Every time I see a assertion failure in the log I see this before:

2012-03-12 21:48:49,523 DEBUG [Thread-211] regionserver.StoreScanner(499): Storescanner.peek() is changed where before = rowB/colfamily11:qual1/75366/Put/vlen=6,and after = rowB/colfamily11:qual1/75203/DeleteColumn/vlen=0

The order of if the Put and Delete is sometimes reversed.

The test threads should always see exactly one KV, if the "before" was the Put the thread see 0 KVs, if the "before" was the Delete the threads see 2 KVs.

This debug message comes from StoreScanner to checkReseek. It seems we still some consistency issue with scanning sometimes

Issue Links

• is related to: HBASE-2856 TestAcidGuarantee broken on trunk
• is related to: HBASE-3584 Allow atomic put/delete in one call

Sub-Tasks

• TestAtomicOperation.testMultiRowMutationMultiThreads is still failing occasionally: Closed