Hi, can anyone help with this? I never looked at a dump file before. On Thu, Apr 14, 2022 at 11:59 AM John Smith <java.dev....@gmail.com> wrote:
> Hi, so I have a dump file. What do I look for? > > On Thu, Mar 31, 2022 at 3:28 PM John Smith <java.dev....@gmail.com> wrote: > >> Ok so if there's a leak, if I manually stop the job and restart it from >> the UI multiple times, I won't see the issue because because the classes >> are unloaded correctly? >> >> >> On Thu, Mar 31, 2022 at 9:20 AM huweihua <huweihua....@gmail.com> wrote: >> >>> >>> The difference is that manually canceling the job stops the JobMaster, >>> but automatic failover keeps the JobMaster running. But looking on >>> TaskManager, it doesn't make much difference >>> >>> >>> 2022年3月31日 上午4:01，John Smith <java.dev....@gmail.com> 写道： >>> >>> Also if I manually cancel and restart the same job over and over is it >>> the same as if flink was restarting a job due to failure? >>> >>> I.e: When I click "Cancel Job" on the UI is the job completely unloaded >>> vs when the job scheduler restarts a job because if whatever reason? >>> >>> Lile this I'll stop and restart the job a few times or maybe I can trick >>> my job to fail and have the scheduler restart it. Ok let me think about >>> this... >>> >>> On Wed, Mar 30, 2022 at 10:24 AM 胡伟华 <huweihua....@gmail.com> wrote: >>> >>>> So if I run the same jobs in my dev env will I still be able to see the >>>> similar dump? >>>> >>>> I think running the same job in dev should be reproducible, maybe you >>>> can have a try. >>>> >>>> If not I would have to wait at a low volume time to do it on >>>> production. Aldo if I recall the dump is as big as the JVM memory right so >>>> if I have 10GB configed for the JVM the dump will be 10GB file? >>>> >>>> Yes, JMAP will pause the JVM, the time of pause depends on the size to >>>> dump. you can use "jmap -dump:live" to dump only the reachable objects, >>>> this will take a brief pause >>>> >>>> >>>> >>>> 2022年3月30日 下午9:47，John Smith <java.dev....@gmail.com> 写道： >>>> >>>> I have 3 task managers (see config below). There is total of 10 jobs >>>> with 25 slots being used. >>>> The jobs are 100% ETL I.e; They load Json, transform it and push it to >>>> JDBC, only 1 job of the 10 is pushing to Apache Ignite cluster. >>>> >>>> FOR JMAP. I know that it will pause the task manager. So if I run the >>>> same jobs in my dev env will I still be able to see the similar dump? I I >>>> assume so. If not I would have to wait at a low volume time to do it on >>>> production. Aldo if I recall the dump is as big as the JVM memory right so >>>> if I have 10GB configed for the JVM the dump will be 10GB file? >>>> >>>> >>>> # Operating system has 16GB total. >>>> env.ssh.opts: -l flink -oStrictHostKeyChecking=no >>>> >>>> cluster.evenly-spread-out-slots: true >>>> >>>> taskmanager.memory.flink.size: 10240m >>>> taskmanager.memory.jvm-metaspace.size: 2048m >>>> taskmanager.numberOfTaskSlots: 16 >>>> parallelism.default: 1 >>>> >>>> high-availability: zookeeper >>>> high-availability.storageDir: file:///mnt/flink/ha/flink_1_14/ >>>> high-availability.zookeeper.quorum: ... >>>> high-availability.zookeeper.path.root: /flink_1_14 >>>> high-availability.cluster-id: /flink_1_14_cluster_0001 >>>> >>>> web.upload.dir: /mnt/flink/uploads/flink_1_14 >>>> >>>> state.backend: rocksdb >>>> state.backend.incremental: true >>>> state.checkpoints.dir: file:///mnt/flink/checkpoints/flink_1_14 >>>> state.savepoints.dir: file:///mnt/flink/savepoints/flink_1_14 >>>> >>>> On Wed, Mar 30, 2022 at 2:16 AM 胡伟华 <huweihua....@gmail.com> wrote: >>>> >>>>> Hi, John >>>>> >>>>> Could you tell us you application scenario? Is it a flink session >>>>> cluster with a lot of jobs? >>>>> >>>>> Maybe you can try to dump the memory with jmap and use tools such as >>>>> MAT to analyze whether there are abnormal classes and classloaders >>>>> >>>>> >>>>> > 2022年3月30日 上午6:09，John Smith <java.dev....@gmail.com> 写道： >>>>> > >>>>> > Hi running 1.14.4 >>>>> > >>>>> > My tasks manager still fails with java.lang.OutOfMemoryError: >>>>> Metaspace. The metaspace out-of-memory error has occurred. This can mean >>>>> two things: either the job requires a larger size of JVM metaspace to load >>>>> classes or there is a class loading leak. >>>>> > >>>>> > I have 2GB of metaspace configed >>>>> taskmanager.memory.jvm-metaspace.size: 2048m >>>>> > >>>>> > But the task nodes still fail. >>>>> > >>>>> > When looking at the UI metrics, the metaspace starts low. Now I see >>>>> 85% usage. It seems to be a class loading leak at this point, how can we >>>>> debug this issue? >>>>> >>>>> >>>> >>>
