How does a JVM process allocate its memory? - java

I have a little gap in understanding how a JVM process allocates its own memory. As far as I know
RSS = Heap size + MetaSpace + OffHeap size
where OffHeap consists of thread stacks, direct buffers, mapped files (libraries and jars) and JVM code itself;
At the moment I’m trying to analyze my Java application (Spring Boot + Infinispan) which RSS is 779M (it runs in a docker container, so pid 1 is ok):
[ root#daf5a5ae9bb7:/data ]$ ps -o rss,vsz,sz 1
RSS VSZ SZ
798324 6242160 1560540
According to jvisualvm, committed Heap size is 374M
Metasapce size is 89M
In other words, I want to explain 799M - (374M + 89M) = 316M of OffHeap memory.
My app has (in average) 36 live threads.
Each of these threads consumes 1M:
[ root#fac6d0dfbbb4:/data ]$ java -XX:+PrintFlagsFinal -version |grep ThreadStackSize
intx CompilerThreadStackSize = 0
intx ThreadStackSize = 1024
intx VMThreadStackSize = 1024
So, here we can add 36M.
The only place where the app uses DirectBuffer is NIO. As far as I can see from JMX, it doesn’t consume a lot of resources - only 98K
The last step is mapped libs and jars. But according to pmap (full output)
[ root#daf5a5ae9bb7:/data ]$ pmap -x 1 | grep ".so.*" | awk '{ sum+=$3} END {print sum}'
12896K
plus
root#daf5a5ae9bb7:/data ]$ pmap -x 1 | grep “.jar" | awk '{ sum+=$3} END {print sum}'
9720K
we only have 20M here.
Hence, we still have to explain 316M - (36M + 20M) = 260M :(
Does anyone have any idea what I missed?

Approach:
You may want to use Java HotSpot Native Memory Tracking (NMT).
This may give you an exact list of memory allocated by the JVM, splitted up into the different areas heap, classes, threads, code, GC, compiler, internal, symbols, memory tracking, pooled free chunks, and unknown.
Usage:
You can start your application with -XX:NativeMemoryTracking=summary.
Observations of the current heap can be done with jcmd <pid> VM.native_memory summary.
Where to find jcmd / pid:
On a default OpedJDK installation on Ubuntu this can be found at /usr/bin/jcmd.
By just running jcmd without any parameter, you get a list of running Java applications.
user#pc:~$ /usr/bin/jcmd
5169 Main <-- 5169 is the pid
Output:
You will then receive a complete overview over your heap, looking something like the following:
Total: reserved=664192KB, committed=253120KB <--- total memory tracked by Native Memory Tracking
Java Heap (reserved=516096KB, committed=204800KB) <--- Java Heap
(mmap: reserved=516096KB, committed=204800KB)
Class (reserved=6568KB, committed=4140KB) <--- class metadata
(classes #665) <--- number of loaded classes
(malloc=424KB, #1000) <--- malloc'd memory, #number of malloc
(mmap: reserved=6144KB, committed=3716KB)
Thread (reserved=6868KB, committed=6868KB)
(thread #15) <--- number of threads
(stack: reserved=6780KB, committed=6780KB) <--- memory used by thread stacks
(malloc=27KB, #66)
(arena=61KB, #30) <--- resource and handle areas
Code (reserved=102414KB, committed=6314KB)
(malloc=2574KB, #74316)
(mmap: reserved=99840KB, committed=3740KB)
GC (reserved=26154KB, committed=24938KB)
(malloc=486KB, #110)
(mmap: reserved=25668KB, committed=24452KB)
Compiler (reserved=106KB, committed=106KB)
(malloc=7KB, #90)
(arena=99KB, #3)
Internal (reserved=586KB, committed=554KB)
(malloc=554KB, #1677)
(mmap: reserved=32KB, committed=0KB)
Symbol (reserved=906KB, committed=906KB)
(malloc=514KB, #2736)
(arena=392KB, #1)
Memory Tracking (reserved=3184KB, committed=3184KB)
(malloc=3184KB, #300)
Pooled Free Chunks (reserved=1276KB, committed=1276KB)
(malloc=1276KB)
Unknown (reserved=33KB, committed=33KB)
(arena=33KB, #1)
This gives a detailed overview of the different memory areas used by the JVM, and also shows the reserved and commited memory.
I don't know of a technique that gives you a more detailed memory consumption list.
Further reading:
You can also use -XX:NativeMemoryTracking=detail in combination with further jcmd commands. A more detailed explaination can be found at Java Platform, Standard Edition Troubleshooting Guide - 2.6 The jcmd Utility. You can check possible commands via "jcmd <pid> help"

Related

Java Native Memory 'Other' section consumes a lot of memory

Prerequisites
Application is run in docker-container with Java openjdk version "13.0.1" with these options:
-Xmx6G -XX:MaxHeapFreeRatio=30 -XX:MinHeapFreeRatio=10 -XX:+AlwaysActAsServerClassMachine -XX:+UseContainerSupport -XX:+HeapDumpOnOutOfMemoryError -XX:+ExitOnOutOfMemoryError -XX:HeapDumpPath==/.../crush.hprof -XX:+UnlockDiagnosticVMOptions -XX:NativeMemoryTracking=summary -XX:+PrintNMTStatistics -Xlog:gc*:file=/var/log/.../log.gc.log:time::filecount=5,filesize=100000
When I run jcmd 1 VM.native_memory, I get this:
Total: reserved=9081562KB, committed=1900002KB
- Java Heap (reserved=6291456KB, committed=896000KB)
(mmap: reserved=6291456KB, committed=896000KB)
- Class (reserved=1221794KB, committed=197034KB)
(classes #34434)
( instance classes #32536, array classes #1898)
(malloc=7330KB #121979)
(mmap: reserved=1214464KB, committed=189704KB)
( Metadata: )
( reserved=165888KB, committed=165752KB)
( used=161911KB)
( free=3841KB)
( waste=0KB =0.00%)
( Class space:)
( reserved=1048576KB, committed=23952KB)
( used=21501KB)
( free=2451KB)
( waste=0KB =0.00%)
- Thread (reserved=456661KB, committed=50141KB)
(thread #442)
(stack: reserved=454236KB, committed=47716KB)
(malloc=1572KB #2654)
(arena=853KB #882)
- Code (reserved=255027KB, committed=100419KB)
(malloc=7343KB #26005)
(mmap: reserved=247684KB, committed=93076KB)
- GC (reserved=316675KB, committed=116459KB)
(malloc=47311KB #70516)
(mmap: reserved=269364KB, committed=69148KB)
- Compiler (reserved=1429KB, committed=1429KB)
(malloc=1634KB #2498)
(arena=18014398509481779KB #5)
- Internal (reserved=2998KB, committed=2998KB)
(malloc=2962KB #5480)
(mmap: reserved=36KB, committed=36KB)
- Other (reserved=446581KB, committed=446581KB)
(malloc=446581KB #368)
- Symbol (reserved=36418KB, committed=36418KB)
(malloc=34460KB #906917)
(arena=1958KB #1)
- Native Memory Tracking (reserved=18786KB, committed=18786KB)
(malloc=587KB #8291)
(tracking overhead=18199KB)
- Shared class space (reserved=11180KB, committed=11180KB)
(mmap: reserved=11180KB, committed=11180KB)
- Arena Chunk (reserved=19480KB, committed=19480KB)
(malloc=19480KB)
- Logging (reserved=7KB, committed=7KB)
(malloc=7KB #271)
- Arguments (reserved=17KB, committed=17KB)
(malloc=17KB #471)
- Module (reserved=1909KB, committed=1909KB)
(malloc=1909KB #11057)
- Safepoint (reserved=8KB, committed=8KB)
(mmap: reserved=8KB, committed=8KB)
- Synchronization (reserved=1136KB, committed=1136KB)
(malloc=1136KB #6628)
Here we can see that 'Other' section consumes 446581 KB whereas total committed memory is 1900002 KB.
So, 'Other' section takes 23% of all committed memory!
Also this memory is not freed when application is running.
Because of this I changed java flag -XX:NativeMemoryTracking=summary to -XX:NativeMemoryTracking=detail to check where memory is allocated and got this 2 strange blocks of memory:
[0x00007f8db4b32bae] Unsafe_AllocateMemory0+0x8e
[0x00007f8da416e7db]
(malloc=298470KB type=Other #286)
[0x00007f8db4b32bae] Unsafe_AllocateMemory0+0x8e
[0x00007f8d9b84bc90]
(malloc=148111KB type=Other #82)
Analyze
I tried to use async-profiler to check event Unsafe_AllocateMemory0.
I run async-profiler as agent like this:
java -agentpath:/async-profiler/build/libasyncProfiler.so=start,event=itimer,Unsafe_AllocateMemory0,file=/var/log/.../unsafe_allocate_memory.html
And got this flamegraph: https://i.stack.imgur.com/PbE5D.png
Also, I tried to profile events malloc,mmap,mprotect. malloc showed the same flamegraph as event Unsafe_AllocateMemory0, but flamegraphs for mmap and mprotect were empty.
I thought that problem can be related with C2 compiler and disabled it, but after restart nothing changed - the 'Other' section still occupied a lot of memory memory. Moreover, this application is long-living and I'm not sure that disabling C2 can be a good idea.
I tried to use jeprof to check which part of code executes os.malloc
I run java application like this:
LD_PRELOAD=/usr/local/lib/libjemalloc.so MALLOC_CONF=prof:true,lg_prof_interval:30,lg_prof_sample:17 exec java -jar /srv/app/myapp.jar
After 10+ minutes I used jeprof and got this: https://i.stack.imgur.com/45adD.gif
And again there are 2 blocks of memory which occupied many native memory.
Result
I cannot find the place, which allocates so much memory.
Maybe someone can recommend how to spot the root cause of this problem? And what steps do I need to take to avoid this problem?
UPDATE 1
Thanks to apangin I have finally found the place, where so much memory is occupied!
It's related to Redisson/Lettuce, which are using Netty under the hood: flamegraph
I used experimental native mode and run java:
java -agentpath:/async-profiler/build/libasyncProfiler.so=start,event=nativemem,file=/var/log/.../profile.jfr -jar /srv/app/myapp.jar
Your async-profilers arguments seem wrong.
Change event=itimer,Unsafe_AllocateMemory0 to event=Unsafe_AllocateMemory0
async-profiler also has an experimental nativemem mode specifically for finding native memory leaks. See https://github.com/jvm-profiling-tools/async-profiler/discussions/491 for the details.
Other section in NMT typically includes off-heap memory allocated with Unsafe.allocateMemory, in particular, Direct ByteBuffers.

How to read heap status with jdk 11?

With jdk 8 these were my steps to figure out how much memory is being consumed while a process is running:
/usr/java/latest/bin>: ./jps
27116 Main
7591 Jps
2879 AmbusProcessor
Then picked up process id to check the status of the heap :
/usr/java/latest/bin>: ./jmap -heap 2879
Attaching to process ID 2879, please wait...
Debugger attached successfully.
Server compiler detected.
JVM version is 24.45-b08
using thread-local object allocation.
Parallel GC with 13 thread(s)
Heap Configuration:
MinHeapFreeRatio = 40
MaxHeapFreeRatio = 70
MaxHeapSize = 68719476736 (65536.0MB)
NewSize = 1310720 (1.25MB)
MaxNewSize = 17592186044415 MB
OldSize = 5439488 (5.1875MB)
NewRatio = 2
SurvivorRatio = 8
PermSize = 21757952 (20.75MB)
MaxPermSize = 134217728 (128.0MB)
G1HeapRegionSize = 0 (0.0MB)
Heap Usage:
PS Young Generation
Eden Space:
capacity = 15427698688 (14713.0MB)
used = 9122094480 (8699.507217407227MB)
free = 6305604208 (6013.492782592773MB)
59.128031111311266% used
From Space:
capacity = 2062024704 (1966.5MB)
used = 813973552 (776.2656707763672MB)
free = 1248051152 (1190.2343292236328MB)
39.474481097196396% used
To Space:
capacity = 1944059904 (1854.0MB)
used = 0 (0.0MB)
free = 1944059904 (1854.0MB)
0.0% used
PS Old Generation
capacity = 8520204288 (8125.5MB)
used = 6649238896 (6341.208358764648MB)
free = 1870965392 (1784.2916412353516MB)
78.04083882548333% used
PS Perm Generation
capacity = 31981568 (30.5MB)
used = 16156728 (15.408256530761719MB)
free = 15824840 (15.091743469238281MB)
50.518873871349896% used
6141 interned Strings occupying 609896 bytes.
I am looking for a way to read the status that should look like the above example, However, not finding an option like that with openjdk 11. I have tried all possible option on jmap on openjdk11.
Is there a way still to get that kind of status reading with openjdk11?
I am trying to dump exactly when the outOfMemory is happening
For newer Java versions like JDK 11 you can use this command:
jhsdb jmap --heap --pid <pid>
Output is almost the same as with Java 8 and jmap.
There are some JVM options that may help you by logging GC info:
-XX:+PrintGCDetails
-XX:+PrintGCDateStamps
-XX:+PrintHeapAtGC
-XX:+PrintTenuringDistribution
-XX:+PrintGCApplicationStoppedTime
-XX:+HeapDumpOnOutOfMemoryError
-XX:+UseGCLogFileRotation
-XX:NumberOfGCLogFiles=10
-XX:GCLogFileSize=10M
The file created by HeapDumpOnOutOfMemoryError can be analyzed with tools shipped with the JDK. See also https://docs.oracle.com/javase/7/docs/webnotes/tsg/TSG-VM/html/clopts.html
edit: There's also some official docs about debugging memory issues in Java 11: https://docs.oracle.com/en/java/javase/11/troubleshoot/troubleshoot-memory-leaks.html

Mallet: OutOfMemoryError: Java heap space

While training data in Mallet, the processed stopped because of OutOfMemoryError. Attribute MEMORY in bin/mallet has already been set to 3GB. The size of training file output.mallet is only 31 MB. I have tried to reduce the training data size. But it still throws the same error:
a161115#a161115-Inspiron-3250:~/dev/test_models/Mallet$ bin/mallet train-classifier --input output.mallet --trainer NaiveBayes --training-portion 0.0001 --num-trials 10
Training portion = 1.0E-4
Unlabeled training sub-portion = 0.0
Validation portion = 0.0
Testing portion = 0.9999
-------------------- Trial 0 --------------------
Trial 0 Training NaiveBayesTrainer with 7 instances
Exception in thread "main" java.lang.OutOfMemoryError: Java heap space
at cc.mallet.types.Multinomial$Estimator.setAlphabet(Multinomial.java:309)
at cc.mallet.classify.NaiveBayesTrainer.setup(NaiveBayesTrainer.java:251)
at cc.mallet.classify.NaiveBayesTrainer.trainIncremental(NaiveBayesTrainer.java:200)
at cc.mallet.classify.NaiveBayesTrainer.train(NaiveBayesTrainer.java:193)
at cc.mallet.classify.NaiveBayesTrainer.train(NaiveBayesTrainer.java:59)
at cc.mallet.classify.tui.Vectors2Classify.main(Vectors2Classify.java:415)
I would appriciate any help or insights into this problem
EDIT: this is my bin/mallet file.
#!/bin/bash
malletdir=`dirname $0`
malletdir=`dirname $malletdir`
cp=$malletdir/class:$malletdir/lib/mallet-deps.jar:$CLASSPATH
#echo $cp
MEMORY=10g
CMD=$1
shift
help()
{
cat <<EOF
Mallet 2.0 commands:
import-dir load the contents of a directory into mallet instances (one per file)
import-file load a single file into mallet instances (one per line)
import-svmlight load SVMLight format data files into Mallet instances
info get information about Mallet instances
train-classifier train a classifier from Mallet data files
classify-dir classify data from a single file with a saved classifier
classify-file classify the contents of a directory with a saved classifier
classify-svmlight classify data from a single file in SVMLight format
train-topics train a topic model from Mallet data files
infer-topics use a trained topic model to infer topics for new documents
evaluate-topics estimate the probability of new documents under a trained model
prune remove features based on frequency or information gain
split divide data into testing, training, and validation portions
bulk-load for big input files, efficiently prune vocabulary and import docs
Include --help with any option for more information
EOF
}
CLASS=
case $CMD in
import-dir) CLASS=cc.mallet.classify.tui.Text2Vectors;;
import-file) CLASS=cc.mallet.classify.tui.Csv2Vectors;;
import-svmlight) CLASS=cc.mallet.classify.tui.SvmLight2Vectors;;
info) CLASS=cc.mallet.classify.tui.Vectors2Info;;
train-classifier) CLASS=cc.mallet.classify.tui.Vectors2Classify;;
classify-dir) CLASS=cc.mallet.classify.tui.Text2Classify;;
classify-file) CLASS=cc.mallet.classify.tui.Csv2Classify;;
classify-svmlight) CLASS=cc.mallet.classify.tui.SvmLight2Classify;;
train-topics) CLASS=cc.mallet.topics.tui.TopicTrainer;;
infer-topics) CLASS=cc.mallet.topics.tui.InferTopics;;
evaluate-topics) CLASS=cc.mallet.topics.tui.EvaluateTopics;;
prune) CLASS=cc.mallet.classify.tui.Vectors2Vectors;;
split) CLASS=cc.mallet.classify.tui.Vectors2Vectors;;
bulk-load) CLASS=cc.mallet.util.BulkLoader;;
run) CLASS=$1; shift;;
*) echo "Unrecognized command: $CMD"; help; exit 1;;
esac
java -Xmx$MEMORY -ea -Djava.awt.headless=true -Dfile.encoding=UTF-8 -server -classpath "$cp" $CLASS "$#"
It's also worth mentioning that my original training file has 60,000 items. When I reduce the number of items (20,000 instances), training will run like normal, but uses about 10GB RAM.
Check the call to Java in bin/mallet and add the flag -Xmx3g, making sure there isn't another Xmx in it; if so, edit that one).
I usually change both files: mallet files and set the memory to maximum
Mallet.batjava -Xmx%MALLET_MEMORY% -ea -Dfile.encoding=%MALLET_ENCODING% -classpath %MALLET_CLASSPATH% %CLASS% %MALLET_ARGS%
and
java -Xmx$MEMORY -ea -Djava.awt.headless=true -Dfile.encoding=UTF-8 -server -classpath "$cp" $CLASS "$#"
I replaced the bold %MALLET_MEMORY% and $MEMORY with the memory I want: e.g. 4G

Hive Query Failing ( AMI - 3.11.0 , Hive- 0.13.1)

Diagnostic Messages for this Task: Container [pid=3347,containerID=container_1490354262227_0013_01_000104] is running beyond physical memory limits. Current usage: 1.0 GB of 1 GB physical memory used; 1.5 GB of 5 GB virtual memory used. Killing container. Dump of the process-tree for container_1490354262227_0013_01_000104 : |- PID PPID PGRPID SESSID CMD_NAME USER_MODE_TIME(MILLIS) SYSTEM_TIME(MILLIS) VMEM_USAGE(BYTES) RSSMEM_USAGE(PAGES) FULL_CMD_LINE |- 3360 3347 3347 3347 (java) 7596 396 1537003520 262629 /usr/java/latest/bin/java -Djava.net.preferIPv4Stack=true -Dhadoop.metrics.log.level=WARN -Xmx864m -Djava.io.tmpdir=/mnt3/var/lib/hadoop/tmp/nm-local-dir/usercache/hadoop/appcache/application_1490354262227_0013/container_1490354262227_0013_01_000104/tmp -Dlog4j.configuration=container-log4j.properties -Dyarn.app.container.log.dir=/mnt/var/log/hadoop/userlogs/application_1490354262227_0013/container_1490354262227_0013_01_000104 -Dyarn.app.container.log.filesize=0 -Dhadoop.root.logger=INFO,CLA org.apache.hadoop.mapred.YarnChild 10.35.178.86 49938 attempt_1490354262227_0013_m_000004_3 104 |- 3347 2563 3347 3347 (bash) 0 1 115806208 698 /bin/bash -c /usr/java/latest/bin/java -Djava.net.preferIPv4Stack=true -Dhadoop.metrics.log.level=WARN -Xmx864m -Djava.io.tmpdir=/mnt3/var/lib/hadoop/tmp/nm-local-dir/usercache/hadoop/appcache/application_1490354262227_0013/container_1490354262227_0013_01_000104/tmp -Dlog4j.configuration=container-log4j.properties -Dyarn.app.container.log.dir=/mnt/var/log/hadoop/userlogs/application_1490354262227_0013/container_1490354262227_0013_01_000104 -Dyarn.app.container.log.filesize=0 -Dhadoop.root.logger=INFO,CLA org.apache.hadoop.mapred.YarnChild 10.35.178.86 49938 attempt_1490354262227_0013_m_000004_3 104 1>/mnt/var/log/hadoop/userlogs/application_1490354262227_0013/container_1490354262227_0013_01_000104/stdout 2>/mnt/var/log/hadoop/userlogs/application_1490354262227_0013/container_1490354262227_0013_01_000104/stderr
Container [pid=3347,containerID=container_1490354262227_0013_01_000104] is running beyond physical memory limits. Current usage: 1.0 GB of 1 GB physical memory used; 1.5 GB of 5 GB virtual memory used.
Looks like your process needs more memory and it is exceeding the defined limit.
You need to increase the container size
SET hive.tez.container.size=4096MB
SET hive.auto.convert.join.noconditionaltask.size=1370MB
Read more about this here.
If it is failing on reducer:
Add distribute by partition key to the query. It will distribute
data between reducers and as a result reducers will create less
partitions and consume less memory.
insert overwrite table items_s3_table PARTITION(w_id) select pk, cId,
fcsku, cType, disposition, cReferenceId, snapshotId, quantity, w_id
from items_dynamodb_table distribute by w_id;
Try to decrease bytes per reducer. Decreasing this parameter will increase parallelizm (the number of reducers) and may reduce memory consumption per reducer. hive.exec.reducers.bytes.per.reducer=67108864;
Adjust memory settings if nothing helps.
For mappers:
mapreduce.map.memory.mb=4096;
mapreduce.map.java.opts=-Xmx3000m;
For reducers:
mapreduce.reduce.memory.mb=4096;
mapreduce.reduce.java.opts=-Xmx3000m;

Java OutOfMemory Error

I am seeing an OutOfMemory problem and I am not sure it is the PERM GEN area or the heap space. The error message does not say anything about which area ran out of memory.
Here is a partial stack trace:
The following is information that may be useful to the developer of BETWEENNESS: java.lang.OutOfMemoryError at java.util.zip.ZipFile.open(Native Method) at java.util.zip.ZipFile.(ZipFile.java:127) at java.util.zip.ZipFile.(ZipFile.java:143) at com..util.internal.ZipFiles.unzip(ZipFiles.java:91)
I looked at the heap space just before it ran out of memory using the jmap -heap command:
using thread-local object allocation.
Parallel GC with 23 thread(s)
Heap Configuration:
MinHeapFreeRatio = 40
MaxHeapFreeRatio = 70
MaxHeapSize = 31675383808 (30208.0MB)
NewSize = 1310720 (1.25MB)
MaxNewSize = 17592186044415 MB
OldSize = 5439488 (5.1875MB)
NewRatio = 2
SurvivorRatio = 8
PermSize = 21757952 (20.75MB)
MaxPermSize = 536870912 (512.0MB)
Heap Usage:
PS Young Generation
Eden Space:
capacity = 9762177024 (9309.9375MB)
used = 7286558512 (6949.003707885742MB)
free = 2475618512 (2360.933792114258MB)
74.64071276403028% used
From Space:
capacity = 396230656 (377.875MB)
used = 340623360 (324.84375MB)
free = 55607296 (53.03125MB)
85.96592788620576% used
To Space:
capacity = 398131200 (379.6875MB)
used = 0 (0.0MB)
free = 398131200 (379.6875MB)
0.0% used
PS Old Generation
capacity = 1992163328 (1899.875MB)
used = 1455304512 (1387.8865356445312MB)
free = 536858816 (511.98846435546875MB)
73.05146578825087% used
PS Perm Generation
capacity = 418578432 (399.1875MB)
used = 418567008 (399.1766052246094MB)
free = 11424 (0.010894775390625MB)
99.99727076238844% used }
And also, I had supplied the following arguments to the JVM: -XX:+HeapDumpOnOutOfMemoryError -XX:HeapDumpPath=/tmp/ but I do not see any heap.
My questions is why is the heap not being generated and how do I figure out which part of the JVm is getting full.
Thanks.
Your provided information says, that your PermGen is 99% full. And your Heap is already 73% full. So increasing both would not be bad at all.
Further you could activate the garbage collector's logging with -XX:+PrintGCDetails to get detailed information on how your JVM is using memory. Additionally activate -XX:+PrintGCTimeStamps and -XX:+PrintGCDateStamps. -Xloggc:$filename sends the logs to a file, which you could easily analyze with something like IMB PMAT tool or GCViewer.
Additionally you should consider using VisualVM to monitor your application while running.
Besides:
A colleague of mine found a smart way to get a heapdump many times faster through gdb:
cat > /tmp/dodump <<EOF
gcore jvm.core
detach
quit
EOF
time gdb --batch --command=/tmp/dodump --pid=`pgrep java`
jmap -dump:format=b,file=jvm.hprof `which java` jvm.core
rm jvm.core
gzip -9 jvm.hprof
Source
Credits go fully to him.
According to stack trace, OutOfMemoryError happens inside ZipFile.open() native method. This means that the problem has nothing to do with Java Heap size nor with PermGen. It is likely related with ZIP cache which is malloc'ed or mmap'ed internally by JDK library.
Try adding -Dsun.zip.disableMemoryMapping=true JVM option to see if it helps.
How large is ZIP file being opened?

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