[Gluster-users] reading from local replica?

[Jeff Darcy]

> In short, it would seem that either were I to use geo-repliciation,
> whether recommended or not in this kind of usage, I'd need to own both
> which volume to mount and what to do with writes when the client has
> chosen to mount the slave.

True.  Various active/active geo-replication solutions have been on
the road map for some time, but in each release there are other things
deemed more important.  :(

> Finally, given that ping times between regions are typically in excess
> of 200 ms in my case, would you strongly discourage AFR usage?

Pretty strongly.  The AFR write protocol is quite latency-sensitive.
Obviously, this affects performance.  Also, as RTT increases it
becomes harder and harder to tune things so that network "brownouts"
don't become full partitions.  If the read-replica selection options
worked, then reads should be OK and an almost entirely read-only
workload might be OK.  Otherwise, I'd say you're likely to have a bad
time.