Greetings and happy new year for all, best wishes for the new year to come with, I pray, the human kind victory against pandemic and world famine
I try to interpret the output from nfsiostat but I can’t have particular clues concerning any “bottleneck” in a classic inner network nfs connexion.
The output says:
192.168.0.3:/nfsshares/BTRFS3 mounted on /nfsshares/BTRFS3:
ops/s rpc bklog 93.000 0.000
read: ops/s kB/s kB/op retrans avg RTT (ms) avg exe (ms)
95.400 48869.023 512.254 0 (0.0%) 100.234 100.244
write: ops/s kB/s kB/op retrans avg RTT (ms) avg exe (ms)
0.000 0.000 0.000 0 (0.0%) 0.000 0.000
the avg RTT seems to be the key datas indicating the NFS is well/badly working.
I can not state that “100.234” is a high latency or a low latency – I’m moving files from nfs server to a usb 3.0 drive (baddest situation) thru a nfs client on which the usb drive is connected.
Looking at iotop on both machines, I got 26% I/O on server BUT 98% I/O on client :{
I did a shell command forgetting the trailing “&” to move the files from the BTRFS mouting point to the usb drive – I don’t know if it would have had an impact on I/O.
The files moved are particulary big (1.0 Gb in average).
The server is 15.1 and the client is 15.2.
The server has a nfsmount.conf with those directives…
NFSMount_Global_Options ]
Defaultvers=3
Proto=tcp
Acl=False
Hard=True
Rsize=262144k
Wsize=262144k
Bsize=32k
Timeo=125
mountport=4001
mountproto=tcp
mounvers=3
Server Port
Port=4000
…got exactly the same on client side.
I use autofs to mount “at demand” the nfs shares with this configuration
BTRFS3 -rw,hard,async,locale=fr_BE.utf8 192.168.0.3:/nfsshares/BTRFS3
Could somebody indicate me a “range” of “good RTT” in a local network nfs scenario ? At which RTT could I consider the latency high ?
Thank you very much ^^