[Lustre-discuss] Problems & partial success on PPC64 (XServe G5) Debian cluster

['Andreas Dilger']

On Nov 17, 2007  10:09 +0400, Peter Avakian wrote:
> I started reading this thread quite recently; I am not sure how exactly the
> little/big endian would you like to be tested? But I thought you might
> wanted to look at a simple Fortran based program (below) reflects the
> read/write I/O pattern.
> 
> Using little-endian reads and writes a lot faster than big-endian (Linux of
> course). 
> I get 500-550 MB/sec read and 200 to 375 MB/sec write with little-endian
> files 

This appears to just be doing endian conversion in the application data?
Lustre doesn't swap endianness of the data, so that isn't a big performance
issue.  It only needs to swab the requests and metadata if the client and
server are of different endianness and not if they are the same endianness.

Cheers, Andreas
--
Andreas Dilger
Sr. Software Engineer, Lustre Group
Sun Microsystems of Canada, Inc.