[Gluster-users] Poor Gluster performance

[Lars Hanke]

> This looks like the NICs may only be negotiating to 100Mb(max theoretical of 12.5 MB / sec), can you check ethtool on all of your NICs?  Also I like to run iperf between servers and clients and servers and servers before I do anything with gluster, if you aren't getting ~line speed with iperf gluster wont be able to either.  Double check you NICs and your backend and see if you can spot the bottleneck at either of those layers.

Ooops - the client side NIC is set at 100Mb/s, although it supports GB 
and is attached to a GB switch. Replugging the network cable fixed it:

root at gladsheim:/# time `dd if=/dev/zero of=~/mnt/testfile.null bs=1024k 
count=1000; sync`
1000+0 records in
1000+0 records out
1048576000 bytes (1.0 GB) copied, 18.0237 s, 58.2 MB/s

real    0m20.669s
user    0m0.008s
sys     0m2.532s
root at gladsheim:/# time `dd if=~/mnt/testfile.null of=/dev/zero bs=1024k 
count=1000; sync`
1000+0 records in
1000+0 records out
1048576000 bytes (1.0 GB) copied, 9.08082 s, 115 MB/s

real    0m12.118s
user    0m0.012s
sys     0m2.432s

Thanks for your help. Now I got to make up my mind whether 55MB/s write 
speed is sufficient and whether there is any use for a dedicated server 
side network.

Regards,
  - lars.