[Gluster-devel] Question about random and rr scheduler

[Craig Tierney]

I setting up Gluster (1.3.7) with two servers.  I first
tried configuring the clients as round-robin (rr). When I try and write
to the filesystem for the first time, all of the files go
to the first brick.  Subsequent writes will alternate between
the two bricks.  When I try random, the first file is always
created on the first brick.  Subsequent writes always go to
the first brick (never the second).

What I want is round-robin, or a working random.  However,
for round-robin to work for me, I need the chosen server to
be random, not always the first one.

In the long-term, it wouldn't really matter because everything
would average out.  However, I am creating filesystems that
will be temporary, so I need the right behavior in the short term.

Should random do what I need?  Should I look in the code
and see how to get the Round-Robin schedule to start with
a random index?

Thanks,
Craig


-------- client.cfg
volume client-ns
   type protocol/client
   option transport-type ib-sdp/client
   option remote-host w25-ib0
   option remote-subvolume brick-ns
end-volume

volume client-w25
   type protocol/client
   option transport-type ib-sdp/client
   option remote-host w25-ib0
   option remote-subvolume brick
end-volume


volume client-w45
   type protocol/client
   option transport-type ib-sdp/client
   option remote-host w45-ib0
   option remote-subvolume brick
end-volume

volume unify
   type cluster/unify
   subvolumes  client-w25 client-w45
   option namespace client-ns
   option scheduler random
#  option scheduler rr
end-volume


-- 
Craig Tierney (craig.tierney at noaa.gov)