[ https://issues.apache.org/jira/browse/HDFS-16074?page=com.atlassian.jira.plugin.system.issuetabpanels:all-tabpanel ]
Work on HDFS-16074 started by Wei-Chiu Chuang. ---------------------------------------------- > Remove an expensive debug string concatenation > ---------------------------------------------- > > Key: HDFS-16074 > URL: https://issues.apache.org/jira/browse/HDFS-16074 > Project: Hadoop HDFS > Issue Type: Improvement > Affects Versions: 3.0.0-alpha1 > Reporter: Wei-Chiu Chuang > Assignee: Wei-Chiu Chuang > Priority: Major > Labels: pull-request-available > Attachments: Screen Shot 2021-06-16 at 2.32.29 PM.png > > Time Spent: 10m > Remaining Estimate: 0h > > Running a YCSB load query, found that we do an expensive string concatenation > on the write path in DFSOutputStream.writeChunkPrepare(). > Nearly 25% of HDFS client write CPU time is spent here. It is not necessary > because it's supposed to be a debug message. So let's remove it. > {code} > if (currentPacket == null) { > currentPacket = createPacket(packetSize, chunksPerPacket, getStreamer() > .getBytesCurBlock(), getStreamer().getAndIncCurrentSeqno(), false); > DFSClient.LOG.debug("WriteChunk allocating new packet seqno={}," > + " src={}, packetSize={}, chunksPerPacket={}, > bytesCurBlock={}", > currentPacket.getSeqno(), src, packetSize, chunksPerPacket, > getStreamer().getBytesCurBlock() + ", " + this); <---- here > } > {code} -- This message was sent by Atlassian Jira (v8.3.4#803005) --------------------------------------------------------------------- To unsubscribe, e-mail: hdfs-issues-unsubscr...@hadoop.apache.org For additional commands, e-mail: hdfs-issues-h...@hadoop.apache.org