[ https://issues.apache.org/jira/browse/HADOOP-5436?page=com.atlassian.jira.plugin.system.issuetabpanels:all-tabpanel ]
Jakob Homan reopened HADOOP-5436: --------------------------------- > job history directory grows without bound, locks up job tracker on new job > submission > ------------------------------------------------------------------------------------- > > Key: HADOOP-5436 > URL: https://issues.apache.org/jira/browse/HADOOP-5436 > Project: Hadoop Common > Issue Type: Bug > Affects Versions: 0.19.0 > Reporter: Tim Williamson > Attachments: HADOOP-5436.patch > > > An unpleasant surprise upgrading to 0.19: requests to jobtracker.jsp would > take a long time or even time out whenever new jobs where submitted. > Investigation showed the call to JobInProgress.initTasks() was calling > JobHistory.JobInfo.logSubmitted() which in turn was calling > JobHistory.getJobHistoryFileName() which was pegging the CPU for a couple > minutes. Further investigation showed the were 200,000+ files in the job > history folder -- and every submission was creating a FileStatus for them > all, then applying a regular expression to just the name. All this just on > the off chance the job tracker had been restarted (see HADOOP-3245). To make > matters worse, these files cannot be safely deleted while the job tracker is > running, as the disappearance of a history file at the wrong time causes a > FileNotFoundException. > So to summarize the issues: > - having Hadoop default to storing all the history files in a single > directory is a Bad Idea > - doing expensive processing of every history file on every job submission is > a Worse Idea > - doing expensive processing of every history file on every job submission > while holding a lock on the JobInProgress object and thereby blocking the > jobtracker.jsp from rendering is a Terrible Idea (note: haven't confirmed > this, but a cursory glance suggests that's what's going on) > - not being able to clean up the mess without taking down the job tracker is > just Unfortunate -- This message is automatically generated by JIRA. - You can reply to this email to add a comment to the issue online.