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Christian Kunz commented on HADOOP-1874: ---------------------------------------- The test included 1904 (no luck at all without it) and was run with a Sep 14 trunk release including the following patches: - 1719 - 1763 - 1874 (lazy-dfs-ops.2.patch and server-throttle-hack.patch) - 1892 (critical) - 1904 (critical) - 1907 (critical) > lost task trackers -- jobs hang > ------------------------------- > > Key: HADOOP-1874 > URL: https://issues.apache.org/jira/browse/HADOOP-1874 > Project: Hadoop > Issue Type: Bug > Components: fs > Affects Versions: 0.15.0 > Reporter: Christian Kunz > Assignee: Devaraj Das > Priority: Blocker > Attachments: lazy-dfs-ops.1.patch, lazy-dfs-ops.2.patch, > lazy-dfs-ops.4.patch, lazy-dfs-ops.patch, server-throttle-hack.patch > > > This happens on a 1400 node cluster using a recent nightly build patched with > HADOOP-1763 (that fixes a previous 'lost task tracker' issue) running a > c++-pipes job with 4200 maps and 2800 reduces. The task trackers start to get > lost in high numbers at the end of job completion. > Similar non-pipes job do not show the same problem, but is unclear whether it > is related to c++-pipes. It could also be dfs overload when reduce tasks > close and validate all newly created dfs files. I see dfs client rpc timeout > exception. But this alone does not explain the escalation in losing task > trackers. > I also noticed that the job tracker becomes rather unresponsive with rpc > timeout and call queue overflow exceptions. Job Tracker is running with 60 > handlers. -- This message is automatically generated by JIRA. - You can reply to this email to add a comment to the issue online.