Hi Chris,

Would you be willing to run your test with strace and post the output?  That 
will help us figure out what read/write system calls PVFS is getting from your 
app.

Thanks,
-sam

On Dec 14, 2010, at 4:29 PM, Chris Poultney wrote:

> All-
> 
> I'm having a problem where files written to a PVFS volume overwrite the 
> beginning of the file after some output has already been generated, as if 
> lseek() had been called mid-write. The overwriting behavior does not show up 
> on a regular ext3 volume. Sample code is attached. I'd like to know if anyone 
> can duplicate this behavior, because it looks like a bug.
> 
> Essentially what happens is this: given a large (1024+ character) string, I 
> write some portion of the string using a C++ ostream, then write another line:
> 
> out << st.substr(0, N);
> out << "done";
> 
> If N < 1024, everything is fine. If N >= 1024, "done" is written at the 
> beginning of the file, overwriting what was there before.
> 
> I'd love to figure this out!
> 
> Cheers,
> -crispy
> 
> <pvfstest.cpp>_______________________________________________
> Pvfs2-users mailing list
> [email protected]
> http://www.beowulf-underground.org/mailman/listinfo/pvfs2-users


_______________________________________________
Pvfs2-users mailing list
[email protected]
http://www.beowulf-underground.org/mailman/listinfo/pvfs2-users

Reply via email to