[ https://issues.apache.org/jira/browse/HADOOP-15550?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=16519877#comment-16519877 ]
Todd Lipcon commented on HADOOP-15550: -------------------------------------- [~ste...@apache.org] thanks for taking a look. I uploaded a new patch and verified that it has the same effect. I no longer needed to lazy-init, because now it's the classloading of JsonSerialization that triggers Jackson classloading. I figure anyone who classloads the former is probably going to use Jackson and it wasn't worth the lazy load of Jackson. > Avoid static initialization of ObjectMappers > -------------------------------------------- > > Key: HADOOP-15550 > URL: https://issues.apache.org/jira/browse/HADOOP-15550 > Project: Hadoop Common > Issue Type: Bug > Components: performance > Affects Versions: 3.2.0 > Reporter: Todd Lipcon > Assignee: Todd Lipcon > Priority: Minor > Attachments: hadoop-15550.txt, hadoop-15550.txt, hadoop-15550.txt > > > Various classes statically initialize an ObjectMapper READER instance. This > ends up doing a bunch of class-loading of Jackson libraries that can add up > to a fair amount of CPU, even if the reader ends up not being used. This is > particularly the case with WebHdfsFileSystem, which is class-loaded by a > serviceloader even when unused in a particular job. We should lazy-init these > members instead of doing so as a static class member. -- This message was sent by Atlassian JIRA (v7.6.3#76005) --------------------------------------------------------------------- To unsubscribe, e-mail: common-issues-unsubscr...@hadoop.apache.org For additional commands, e-mail: common-issues-h...@hadoop.apache.org