[ https://issues.apache.org/jira/browse/HDFS-16433?page=com.atlassian.jira.plugin.system.issuetabpanels:all-tabpanel ]
Yuanbo Liu resolved HDFS-16433. ------------------------------- Resolution: Not A Problem > The synchronized lock of IncrementalBlockReportManager will slow down the > speed of creating/deleting/finalizing/opening block > ----------------------------------------------------------------------------------------------------------------------------- > > Key: HDFS-16433 > URL: https://issues.apache.org/jira/browse/HDFS-16433 > Project: Hadoop HDFS > Issue Type: Improvement > Reporter: Yuanbo Liu > Priority: Critical > Attachments: image-2022-01-21-22-52-52-912.png > > > The code in IncrementalBlockReportManager.java > {code:java} > synchronized void waitTillNextIBR(long waitTime) { > if (waitTime > 0 && !sendImmediately()) { > try { > wait(ibrInterval > 0 && ibrInterval < waitTime? ibrInterval: waitTime); > } catch (InterruptedException ie) { > LOG.warn(getClass().getSimpleName() + " interrupted"); > } > } > } {code} > We can see that wait(waitime) will hold synchronized, if ibr interval is > enabled or heartbeat time is not reached. The lock will block > notifyNamenodeBlock function which is widely used in > deleting/creating/finalizing/opening blocks, then the speed of DataNode IO > will slow down. Here is the graph of blocking relationship > !image-2022-01-21-22-52-52-912.png|width=976,height=299! > > -- This message was sent by Atlassian Jira (v8.20.1#820001) --------------------------------------------------------------------- To unsubscribe, e-mail: hdfs-issues-unsubscr...@hadoop.apache.org For additional commands, e-mail: hdfs-issues-h...@hadoop.apache.org