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Nick Dimiduk commented on HBASE-15203: -------------------------------------- +1 for branch-1.1. > Reduce garbage created by path.toString() during Checksum verification > ---------------------------------------------------------------------- > > Key: HBASE-15203 > URL: https://issues.apache.org/jira/browse/HBASE-15203 > Project: HBase > Issue Type: Sub-task > Components: regionserver > Reporter: ramkrishna.s.vasudevan > Assignee: ramkrishna.s.vasudevan > Priority: Minor > Fix For: 2.0.0 > > Attachments: HBASE-15203.patch, HBASE-15203_1.patch > > > When we try to read a block we do checksum verification for which we need the > file name in which the block belongs to. So we do Path.toString() every time. > This seems to create around 163MB of char[] that is garbage collected in a > simple scan run. It is also visible in writes but the impact is lesser. In > overall write/read profile the top 2 factors are byte[] and char[]. This > toString() can easily be avoided and reduce its share from the total. To make > it more precise in 1 min of profiling, among the 1.8G of garbage created by > StringBuilder.toString - this path.toString() was contributing around 3.5%. > After the patch this is totally not there. -- This message was sent by Atlassian JIRA (v6.3.4#6332)