[ https://issues.apache.org/jira/browse/HDDS-4228?page=com.atlassian.jira.plugin.system.issuetabpanels:all-tabpanel ]
Glen Geng updated HDDS-4228: ---------------------------- Description: The sac {code:java} 2020-09-10 03:42:08,196 | INFO | SCMAudit | user=root | ip=172.16.90.221 | op=ALLOCATE_BLOCK {owner=7da0b4c4-d053-4fa0-8648-44ff0b8ba1bf, size=268435456, type=RATIS, factor=THREE} | ret=SUCCESS |{code} was: Teragen reported to be slow with low number of mappers compared to HDFS. In my test (one pipeline, 3 yarn nodes) 10 g teragen with HDFS was ~3 mins but with Ozone it was 6 mins. It could be fixed with using more mappers, but when I investigated the execution I found a few problems reagrding to the BufferPool management. 1. IncrementalChunkBuffer is slow and it might not be required as BufferPool itself is incremental 2. For each write operation the bufferPool.allocateBufferIfNeeded is called which can be a slow operation (positions should be calculated). 3. There is no explicit support for write(byte) operations In the flamegraph it's clearly visible that with low number of mappers the client is busy with buffer operations. After the patch the rpc call and the checksum calculation give the majority of the time. > ALLOCATE_BLOCK of scm audit log miss num > ---------------------------------------- > > Key: HDDS-4228 > URL: https://issues.apache.org/jira/browse/HDDS-4228 > Project: Hadoop Distributed Data Store > Issue Type: Improvement > Reporter: Glen Geng > Assignee: Glen Geng > Priority: Minor > > > The sac > {code:java} > 2020-09-10 03:42:08,196 | INFO | SCMAudit | user=root | ip=172.16.90.221 | > op=ALLOCATE_BLOCK {owner=7da0b4c4-d053-4fa0-8648-44ff0b8ba1bf, > size=268435456, type=RATIS, factor=THREE} | ret=SUCCESS |{code} -- This message was sent by Atlassian Jira (v8.3.4#803005) --------------------------------------------------------------------- To unsubscribe, e-mail: ozone-issues-unsubscr...@hadoop.apache.org For additional commands, e-mail: ozone-issues-h...@hadoop.apache.org