# java comitted virtual memory problem **URL:** \ **Category:** Wowza Streaming Engine\ **Created:** [April 20, 2010, 11:39am UTC](https://community.wowza.com/t/java-comitted-virtual-memory-problem/33901 "2010-04-20T11:39:57Z")\ **Posts on this page:** 8\ **Page:** 1
**Author:** ![Sorin\_Vasilescu](https://avatars.discourse-cdn.com/v4/letter/s/c57346/32.png) [@Sorin\_Vasilescu](https://community.wowza.com/u/Sorin_Vasilescu)\ **Post date:** [April 20, 2010, 11:39am UTC](https://community.wowza.com/t/java-comitted-virtual-memory-problem/33901/1 "2010-04-20T11:39:57Z")
Hi, guys, I’m having a problem related to the Java VM that Wowza runs in. I’ve modified the following in setenv.sh: ```auto JAVA_OPTS="-Xmx4500M" JAVA_OPTS="$JAVA_OPTS -server" JAVA_OPTS="$JAVA_OPTS -XX:+UseConcMarkSweepGC -XX:+CMSIncrementalMode -XX:NewSize=1024m" ``` I have 6 GB RAM on the machine, I’m running CentOS 64bit. The Java VM grows in size until it ends up using 3-4 GB of swap and I can’t figure out why. Wowza is the only thing running on that server. The Java VM summary from JConsole is (I’ve replaced the server address with [\*\*\*] for security purposes): ```auto VM Summary Tuesday, April 20, 2010 11:45:10 AM EEST Connection name:* admin@service:jmx:rmi://[***]:8084/jndi/rmi://[***]:8085/jmxrmi Virtual Machine:* Java HotSpot(TM) 64-Bit Server VM version 14.3-b01 Vendor:* Sun Microsystems Inc. Name:* 22791@[***] Uptime:* 7 hours 35 minutes Process CPU time:* 10 hours 6 minutes JIT compiler:* HotSpot 64-Bit Server Compiler Total compile time:* 1 minute Live threads:* ***941 Peak:* *1,025 Daemon threads:* **** 59 Total threads started:* 98,653 Current classes loaded:* 3,105 Total classes loaded:* 3,120 Total classes unloaded:* ***15 Current heap size:* 1,522,709 kbytes Maximum heap size:* 4,503,168 kbytes Committed memory:* 4,503,168 kbytes Pending finalization:* 0 objects Garbage collector:* Name = 'ParNew', Collections = 6,819, Total time spent = 33 minutes Garbage collector:* Name = 'ConcurrentMarkSweep', Collections = 4, Total time spent = 8 minutes Operating System:* Linux 2.6.18-164.11.1.el5 Architecture:* amd64 Number of processors:* 4 Committed virtual memory:* 11,868,356 kbytes Total physical memory:* *6,108,868 kbytes Free physical memory:* **** 98,040 kbytes Total swap space:* 12,550,136 kbytes Free swap space:* *9,883,132 kbytes VM arguments:* -Xmx4500M -XX:+UseConcMarkSweepGC -XX:+CMSIncrementalMode -XX:NewSize=1024m -Djava.net.preferIPv4Stack=true -Dcom.sun.management.jmxremote=true -Dcom.wowza.wms.AppHome=/usr/local/WowzaMediaServer -Dcom.wowza.wms.ConfigURL= -Dcom.wowza.wms.ConfigHome=/usr/local/WowzaMediaServer Class path:* /usr/local/WowzaMediaServer/bin/wms-bootstrap.jar Library path:* /usr/java/jre1.6.0_17/lib/amd64/server:/usr/java/jre1.6.0_17/lib/amd64:/usr/java/jre1.6.0_17/../lib/amd64:/usr/java/packages/lib/amd64:/lib:/usr/lib Boot class path:* /usr/java/jre1.6.0_17/lib/resources.jar:/usr/java/jre1.6.0_17/lib/rt.jar:/usr/java/jre1.6.0_17/lib/sunrsasign.jar:/usr/java/jre1.6.0_17/lib/jsse.jar:/usr/java/jre1.6.0_17/lib/jce.jar:/usr/java/jre1.6.0_17/lib/charsets.jar:/usr/java/jre1.6.0_17/classes ``` So, from what I gather, the heap size is the right size, but the total virtual memory exceeds the heap size by more than twice it’s value. So if it isn’t heap size, what else is eating up all that RAM? ---
**Author:** ![Charlie\_Good](https://sea2.discourse-cdn.com/flex002/user_avatar/community.wowza.com/charlie_good/32/383_2.png) [@Charlie\_Good](https://community.wowza.com/u/Charlie_Good)\ **Post date:** [April 20, 2010, 4:11am UTC](https://community.wowza.com/t/java-comitted-virtual-memory-problem/33901/2 "2010-04-20T04:11:52Z")
I really don’t know what would be causing this. I don’t understand how VM works at a detailed level in linux. Charlie ---
**Author:** ![Richard\_Lanham](https://avatars.discourse-cdn.com/v4/letter/r/c68b51/32.png) [@Richard\_Lanham](https://community.wowza.com/u/Richard_Lanham)\ **Post date:** [June 9, 2010, 4:02pm UTC](https://community.wowza.com/t/java-comitted-virtual-memory-problem/33901/3 "2010-06-09T16:02:08Z")
In that case a RAID 0 or RAID 10 disk array will help. Richard ---
**Author:** ![Guillermo\_Revuelta](https://avatars.discourse-cdn.com/v4/letter/g/6f9a4e/32.png) [@Guillermo\_Revuelta](https://community.wowza.com/u/Guillermo_Revuelta)\ **Post date:** [June 9, 2010, 8:53am UTC](https://community.wowza.com/t/java-comitted-virtual-memory-problem/33901/4 "2010-06-09T08:53:07Z")
I’m researching yet but I’m starting to think that Centos is not the best option for Wowza. I’ll post if I find out. ---
**Author:** ![Guillermo\_Revuelta](https://avatars.discourse-cdn.com/v4/letter/g/6f9a4e/32.png) [@Guillermo\_Revuelta](https://community.wowza.com/u/Guillermo_Revuelta)\ **Post date:** [June 10, 2010, 9:38am UTC](https://community.wowza.com/t/java-comitted-virtual-memory-problem/33901/5 "2010-06-10T09:38:47Z")
It wasn’t Centos finally (I had reasons to suspect) but now it’s free of all charges. It was the java version (1.6.0.18), that is buggy crap. ---
**Author:** ![Sorin\_Vasilescu](https://avatars.discourse-cdn.com/v4/letter/s/c57346/32.png) [@Sorin\_Vasilescu](https://community.wowza.com/u/Sorin_Vasilescu)\ **Post date:** [June 9, 2010, 10:37am UTC](https://community.wowza.com/t/java-comitted-virtual-memory-problem/33901/6 "2010-06-09T10:37:33Z")
> I’m researching yet but I’m starting to think that Centos is not the best option for Wowza. I’ll post if I find out. Well, if you find out something, please share. Also, this problem is, from what I’ve noticed, related to vod, mostly, so disk access. A server with only live streams has no problems. Maybe you could also look into disk access schedulers and other things that might be related. ---
**Author:** ![Sorin\_Vasilescu](https://avatars.discourse-cdn.com/v4/letter/s/c57346/32.png) [@Sorin\_Vasilescu](https://community.wowza.com/u/Sorin_Vasilescu)\ **Post date:** [June 9, 2010, 7:39pm UTC](https://community.wowza.com/t/java-comitted-virtual-memory-problem/33901/7 "2010-06-09T19:39:13Z")
> In that case a RAID 0 or RAID 10 disk array will help. > > Richard The server I was talking about has RAID 0, software I admit. ---
**Author:** ![Sorin\_Vasilescu](https://avatars.discourse-cdn.com/v4/letter/s/c57346/32.png) [@Sorin\_Vasilescu](https://community.wowza.com/u/Sorin_Vasilescu)\ **Post date:** [June 10, 2010, 10:56am UTC](https://community.wowza.com/t/java-comitted-virtual-memory-problem/33901/8 "2010-06-10T10:56:49Z")
> It wasn’t Centos finally (I had reasons to suspect) but now it’s free of all charges. It was the java version (1.6.0.18), that is buggy crap. So updating with another Java version fixed it? What Java version did you update with?