Re: Question about wal files / pg_xlogs

@Adrian,

> Seems to me the settings for nice and ionice above would, on a busy
> machine, slow down the transfer. Has there always been a notable time
> difference in the transfer or has it gotten worse over time?
>
> Yep... I also thought about that. Specially because the master is
constantly getting 100% of IO (we use SATA disks still)...

I'm thinking about removing that `ionice` command... I don't need to
restart Postgres eh?? Just reload the confs?

@John R Pierce,

normally, you would ship the archived wal files to a file server via
> cp-over-nfs or scp, and have the slaves access them as needed via the
> recovery.conf

What if the NFS server goes down? Networking goes down? We have had that
kind of problem in the past, that's why I'm shipping the wal_files to each
slave, separately. Also, to have an extra copy of them.

@Venkata Balaji N,

Not sure why the script is so complex. Do you see any messages in the
> postgresql log file on master ? and on slave ? which indicates the reason
> for delayed shipping of WAL archives. Did you notice any network level
> issues ?

Yes the script is complex.. I've hidden almost all of it for privacy
purpose.. sorry....

I don't see any messages on the log files... not on the master and not on
the slaves as well. I just see the message of the wal_files
being successfully shipped to the slaves.

Also, no networking level issues.. because I got four slaves with streaming
replication and all of them are working fine... also, my backup server has
never failed... so no networking issues.

Thanks,

Patrick