Do your OOMs correlate with the secondary checkpointing? Joep
Sent from my iPhone On Dec 22, 2012, at 7:42 AM, Michael Segel <michael_se...@hotmail.com> wrote: > Hey Silly question... > > How long have you had 27 million files? > > I mean can you correlate the number of files to the spat of OOMs? > > Even without problems... I'd say it would be a good idea to upgrade due to > the probability of a lot of code fixes... > > If you're running anything pre 1.x, going to 1.7 java wouldn't be a good > idea. Having said that... outside of MapR, have any of the distros certified > themselves on 1.7 yet? > > On Dec 22, 2012, at 6:54 AM, Edward Capriolo <edlinuxg...@gmail.com> wrote: > >> I will give this a go. I have actually went in JMX and manually triggered >> GC no memory is returned. So I assumed something was leaking. >> >> On Fri, Dec 21, 2012 at 11:59 PM, Adam Faris <afa...@linkedin.com> wrote: >> >>> I know this will sound odd, but try reducing your heap size. We had an >>> issue like this where GC kept falling behind and we either ran out of heap >>> or would be in full gc. By reducing heap, we were forcing concurrent mark >>> sweep to occur and avoided both full GC and running out of heap space as >>> the JVM would collect objects more frequently. >>> >>> On Dec 21, 2012, at 8:24 PM, Edward Capriolo <edlinuxg...@gmail.com> >>> wrote: >>> >>>> I have an old hadoop 0.20.2 cluster. Have not had any issues for a while. >>>> (which is why I never bothered an upgrade) >>>> >>>> Suddenly it OOMed last week. Now the OOMs happen periodically. We have a >>>> fairly large NameNode heap Xmx 17GB. It is a fairly large FS about >>>> 27,000,000 files. >>>> >>>> So the strangest thing is that every 1 and 1/2 hour the NN memory usage >>>> increases until the heap is full. >>>> >>>> http://imagebin.org/240287 >>>> >>>> We tried failing over the NN to another machine. We change the Java >>> version >>>> from 1.6_23 -> 1.7.0. >>>> >>>> I have set the NameNode logs to debug and ALL and I have done the same >>> with >>>> the data nodes. >>>> Secondary NN is running and shipping edits and making new images. >>>> >>>> I am thinking something has corrupted the NN MetaData and after enough >>> time >>>> it becomes a time bomb, but this is just a total shot in the dark. Does >>>> anyone have any interesting trouble shooting ideas? >
