That was quick.  Sure, I'll take the patch to see if this Java application 
works.

Cheers,
--Scott

From: Boyd Wilson <[email protected]<mailto:[email protected]>>
Date: Wednesday, May 15, 2013 7:38 AM
To: Scott Roberts <[email protected]<mailto:[email protected]>>
Cc: PVFS2-Users 
<[email protected]<mailto:[email protected]>>
Subject: Re: [Pvfs2-users] Executing the Java binary on OrangeFS

Scott,

>From Randy...

I got the code change I made earlier today tested.  We can now make mmap work 
if MAP_SHARED is used.  Essentially the call is reverted under the covers to be 
a MAP_PRIVATE.  To enable the support, all you have to do is load the kmod with 
the new fake_mmap_shared option.

Example:

insmod pvfs2.ko fake_mmap_shared=1

This will be in future releases, but if you want a patch let us know.

-boyd



On Tue, May 14, 2013 at 3:27 PM, Scott Roberts 
<[email protected]<mailto:[email protected]>> wrote:
Hi Boyd,

The Java application we're trying to run doesn't use shared mmap.  That's a 
-very– old bug and I am surprised Sun/Oracle didn't fix it; maybe it breaks 
compatibility with an old application they wanted to support.

If you roll the fake out flag into the next version of OrangeFS we will give it 
a go.  No rush.  Our temporary workaround is to install the JDK on local disk 
on each compute node.

Thanks,
--Scott

From: Boyd Wilson <[email protected]<mailto:[email protected]>>
Date: Tuesday, May 14, 2013 1:50 PM
To: Scott Roberts <[email protected]<mailto:[email protected]>>
Cc: PVFS2-Users 
<[email protected]<mailto:[email protected]>>
Subject: Re: [Pvfs2-users] Executing the Java binary on OrangeFS

This is caused by the JVM requiring shared mmap, when the java app does not 
even need it and the current KM for OrangeFS does not support shared MMAP.  We 
have talked about implementing it, but that would take a while, we also have 
discussed just putting in a fake out flag for the KM.   Do you know if the java 
app you are trying to use actually uses shared mmap or not?  (if not we can 
look at turning around the fake out flag pretty quickly).   This is not limited 
to JVM , some other apps do the same thing (very very few actually use shared 
mmap).

There is also this older java bug report (requesting the JVM not do this), its 
here:
http://bugs.sun.com/bugdatabase/view_bug.do?bug_id=7085890

thanks,
-boyd


On Tue, May 14, 2013 at 12:30 PM, Scott Roberts 
<[email protected]<mailto:[email protected]>> wrote:
Good afternoon,

Has anyone encountered issues executing applications directly from an OrangeFS 
mount?  Most applications like Python, Perl, &c. work fine.  I untarred the 
64-bit version of Java 7 to the location /export/ofs/apps/src with no errors.   
However, executing Java throws this error:

./java -version
mmap failed for CEN and END part of zip file
Error occurred during initialization of VM
java/lang/ClassNotFoundException: error in opening JAR file 
/export/ofs/apps/src/jdk1.7.0_21/jre/lib/rt.jar

Any ideas?

Cheers,
--Scott

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