[HBASE-8420] Port HBASE-6874 Implement prefetching for scanners from 0.89-fb

• Type: Improvement
• Status: Closed
• Priority: Major
• Resolution: Fixed
• Fix Version/s: 0.98.0, 0.95.1
• Hadoop Flags: Reviewed

Release Note

By default, prefetching is enabled in the trunk version (0.95.2 and 0.98). To disable it, users have to set prefetching off in the Scan object.

This patch introduced a configuration hbase.hregionserver.prefetcher.resultsize.max to control how much data we can prefetch. By default, it is 256MB. If there is already more than that much data prefetched, no new prefetching will be scheduled until some prefetched results are retrieved by clients, so there is room again for new prefetching.

• Assignee: Jimmy Xiang
• Reporter: Jimmy Xiang
• Created: 24/Apr/13 18:27
• Updated: 04/Apr/14 03:27
• Resolved: 24/May/13 22:57

Description

This should help scanner performance. We should have it in trunk.

Issue Links

• relates to: HBASE-6874 Implement prefetching for scanners

Sub-Tasks

• Port HBASE-6874 Implement prefetching for scanners from 0.89-fb to 0.94: Closed