Hi, I have a very strange phenomena concerning read performance as tested with iozone (command line: iozone -Ra -n 16G -y 16384k -g 16G -i 0 -i 1):
When running over Infiniband (gen1, openib LND), I get 400MB/s write but only 160MB/s read. This is already a pretty low read speed compared to write. However, it becomes much worse, if I run the same benchmark over GigE: Here I get 105MB/s write (excellent), and only 17MB/s!!! read. I already tried increasing /proc/fs/lustre/llite/fs0/max_read_ahead_mb without much success (changed from 14 to 17MB/s). Any idea how this could be improved? The configuration is as follows: - 1 MDS + 2 OSS with 2 OSTs each. - Kernel 2.6.15.7 with Lustre 1.4.6.1 on both clients and servers. Thanks, Roland _______________________________________________ Lustre-discuss mailing list [email protected] https://mail.clusterfs.com/mailman/listinfo/lustre-discuss
