[Lustre-discuss] lustre client /proc cached reads

[John Parhizgari]

Simply, I would like to be able to access lustre client data statistics 
for each filesystem that excludes statistics for cached reads.

It is my understanding that for the lustre client (at least on version 
1.6.4.2) the /proc lustre stats for the client for each fs 
(/proc/fs/lustre/llite/FSNAME/stats) report the total number of bytes 
read (reported in the line read_bytes), and that this number also 
includes the total number of bytes read using client-cached data.

First of all, is my understanding correct for this version of lustre? 
And does this apply also for newer versions?

It has been suggested to subtract the lustre IO from the network IO to 
get this data, but this is only applicable if the network is dedicated 
to Lustre IO, which is not the case.

For the moment it seems only the number of cached reads are being 
reported in /proc, and not the actual sizes, so this -seems- difficult 
or impossible.

Is there another way (perhaps even in a newer version of lustre) to find 
the true read rate for the lustre client that excludes cached reads?

--
John Parhizgari