Note: "permalinks" may not be as permanent as we would like,
direct links of old sources may well be a few messages off.
On 09/01/14 01:39 AM, Digimer wrote: > Hi all, > > I've been trying to do some tuning with DRBD. The network interface > sustains 1.225 GB/sec tested with iperf (multiple tests, hf and fd). The > disks themselves sustain 1.2 GB/sec sequential writes (975 GB write via > 'dd if=/dev/zero of=/dev/sda5 bs=4M), tested repeatedly and on both > nodes. The storage array is an 8-disk (146 GB 15krpm 2.5" SAS disks on > an LSI RAID controller with a 2208 ASIC). > <snip> Answering some of my own questions; sharing what I've done/tested; I saw (http://www.drbd.org/users-guide/ch-benchmark.html): ==== For freshly enabled DRBD devices, it is normal to see significantly reduced performance on the first dd run. This is due to the Activity Log being "cold" ==== So I am going to let the initial sync finish and try again. I also noticed that I had enabled 'data-integrity-alg' and re-enabled 'disk-flushes no;' and 'md-flushes no;'. I've disabled these and it's already dd'ing at ~650 MB/sec. This is still half of what the storage/network can handle, but it's a mighty scene better than before. :) I'll post more as I experiment/learn. In the meantime, I would very much love to hear feedback, specially from folks with experience tuning for LSI-based controllers and 10 gbps ethernet networks. Thanks! -- Digimer Papers and Projects: https://alteeve.ca/w/ What if the cure for cancer is trapped in the mind of a person without access to education?