Re: rsync and streaming replication

On Nov 17, 2011, at 10:11 AM, Jean-Armel Luce wrote:

> > Also, I believe you said -z seemed to slow it down?
> I confirm

Is there a lot of your data that is already compressed? Either something like images which you are storing as bytea or
largeobjects? Or long text values that pg will itself compress out of line? 

> Today, I tried with command : rsync -rc --block-size=8192
> Rsync duration with blksize=8192 was 31 minutes (yesterday without blocksize, duration was 32 minutes exactly)

That seems not too bad, in that you're sustaining >3GB/min of reading & checksumming. (Some of my earlier comments were
basedon the belief that your db was 20GB.) 

--
Scott Ribe
scott_ribe@elevated-dev.com
http://www.elevated-dev.com/
(303) 722-0567 voice