topic Re: Memory Leak Problem in Alfresco Archive

Memory Leak Problem

habib_adnan — Thu, 31 May 2007 20:19:33 GMT

Hello,I have an Alfresco Instance installed and configured on the following box:Linux 4.2 Kernel 2.6.9JVM 1.5.0_11MySQL 5.0.37Geronimo 1.1.1After loading about 600 Mo worth of content through Alfresco FTP Virtual Server, I am getting a memory leak.After I start the alfresco instance, the JVM use up

Re: Memory Leak Problem

kevinr — Fri, 01 Jun 2007 09:42:02 GMT

Are you sure you have a "leak" - what version of Alfresco are you using? How much memory did you give the JVM? Are there any other processes running on the app-server? Are you using Geronimo for the app-server? If so can you provide more details on how you deployed Alfresco on it.

Thanks,

Kevin

Re: Memory Leak Problem

habib_adnan — Fri, 01 Jun 2007 20:21:24 GMT

Are you sure you have a "leak" - what version of Alfresco are you using? How much memory did you give the JVM? Are there any other processes running on the app-server? Are you using Geronimo for the app-server? If so can you provide more details on how you deployed Alfresco on it.

Thanks,

Kevin

Yes I am running Alfresco 2.0 on Geronimo 1.1.1 All I had to do
is write a deployment plan geronimo-web.xml.

On geronimo app server there is a console that displays continously
the memory used by the jvm. after i start alfresco the app use up all the memory i have configured in JAVA_OPTS

Re: Memory Leak Problem

kevinr — Mon, 04 Jun 2007 09:26:10 GMT

By default Alfresco uses some large internal memory caches - it will use 512MB if it's available very quickly - these can be tuned to be much smaller if you require. As i say, are you sure it's a "leak" - i.e. if you give the server 512MB or 1GB does it actually cause out-of-memory errors or just take all the memory up as cache.

Thanks,

Kevin

Re: Memory Leak Problem

habib_adnan — Thu, 07 Jun 2007 16:36:00 GMT

By default Alfresco uses some large internal memory caches - it will use 512MB if it's available very quickly - these can be tuned to be much smaller if you require. As i say, are you sure it's a "leak" - i.e. if you give the server 512MB or 1GB does it actually cause out-of-memory errors or just take all the memory up as cache.

Thanks,

Kevin

Thanks Kevin for your pointer,

being an ex C developer, I have just panicked seing the VM using all my 1.7 Go RAM, and my server not responding.

In fact I was trying to transfer 400 Mo through the alfresco ftp instance,
but after giving the time to complete, the VM used memory droped to 103 Mo. the 1.6 Go stayed allocated

Cheers

Re: Memory Leak Problem

kevinr — Fri, 08 Jun 2007 13:49:12 GMT

Unfortunately that is the nature of the Java VM rather than Alfresco specifically If you allocate a max of say 512MB to JVM it will eventually consume it all and then garbage collect the memory internally to release it when it hits the ceiling. So it "appears" to leak until the garbage collector does it's trick. It might be worth reading up on the JVM and the various configuration parameters as it can be tuned in many different ways, including controlling how often and what style of garbage collection (multi-threaded, incremental etc.) the VM is using.

As you saw after the big import the garbage collector collected most of the used memory, but the VM has kept the total memory space allocated in use.

Thanks,

Kevin