[ https://issues.apache.org/jira/browse/ACCUMULO-2801?page=com.atlassian.jira.plugin.system.issuetabpanels:all-tabpanel ]
Keith Turner resolved ACCUMULO-2801. ------------------------------------ Resolution: Duplicate > define tablet syncs walog for each tablet in a batch > ---------------------------------------------------- > > Key: ACCUMULO-2801 > URL: https://issues.apache.org/jira/browse/ACCUMULO-2801 > Project: Accumulo > Issue Type: Bug > Affects Versions: 1.5.0, 1.5.1, 1.6.0 > Reporter: Keith Turner > Priority: Major > > When the batch writer sends a batch of mutations for N tablets that were not > currently using a walog, then define tablet will be called for each tablet. > Define tablet will sync the walog. In hadoop 2 hsync is used, which is much > slower than hadoop1 sync calls. If hsync takes 50ms and there are 100 > tablets, then this operation would take 5 secs. The calls to define tablet > do not occur frequently, just when walogs switch or tablets are loaded so the > cost will be amortized. Ideally there could be one walog sync call for all > of the tablets in a batch of mutations. -- This message was sent by Atlassian JIRA (v7.6.3#76005)