Kamal Jain <kjain@xxxxxxxxxxxxxxxxxxx> writes: > I am surprised that handling locking for 8 files might cause major > performance degradation with GFS versus iSCSI-direct. > > As for latency, all the devices are directly connected to a Cisco > 3560G switch and on the same VLAN, so I expect Ethernet/layer-2 > latencies to be sub-millisecond. Also, note that the much faster > iSCSI performance was on the same GbE connections between the same > devices and systems, so network throughput and latency are the same. > > GFS overhead, in handling locking (most likely) and any GFS > filesystem overhead are the likely causes IMO. > > Looking forward to any analysis and guidance you may be able to > provide on getting GFS performance closer to iSCSI-direct. I'm really interested in the outcome of this discussion. Meanwhile I can add that 'gfs_controld -l0' and 'gfs_tool settune /mnt demote_secs 600' (as recommended on this list by the kind developers) helped me tremendously dealing with lots of files. -- Regards, Feri. -- Linux-cluster mailing list Linux-cluster@xxxxxxxxxx https://www.redhat.com/mailman/listinfo/linux-cluster
