[Gluster-users] How gluster parallelize reads

[Gandalf Corvotempesta]

2016-10-03 20:48 GMT+02:00 Jeff Darcy <jdarcy at redhat.com>:
> Basic storage-developer conservatism.  Zero was the behavior before
> read-hash-mode was implemented.  As strongly as some of us might believe
> that such tweaks lead to better behavior - as I did with this one in
> 2012[1] - we've kind of learned the hard way that existing users often
> disagree with our estimations.  Thus, new behavior is often kept as a
> "special" for particular known environments or use cases, and the
> default is left unchanged until there's clear feedback indicating it
> should be otherwise.

That's fine, but i've not found description of these values in docs.
is it documented ?
Anyway, in gerrit you are talking about "local" reads. How could you
have a "local" read? This would be possible only mounting the volume
locally on a server. is this a supported configuration?

And, as you write, the local server ins't always the faster to
response, thus is not a good check.
Probably, a "priority" could be added in mount option, so that when
mounting the gluster volume i can set the preferred host for reads.

Something like this:

mount -t glusterfs -o preferred-read-host=1.2.3.4 server1:/test-volume
/mnt/glusterfs