Re: rsync and streaming replication - Mailing list pgsql-admin

From Scott Ribe
Subject Re: rsync and streaming replication
Date
Msg-id 39A965E0-DE37-41F3-8D69-321419BB8B09@elevated-dev.com
Whole thread Raw
In response to Re: rsync and streaming replication  (Cédric Villemain <cedric.villemain.debian@gmail.com>)
Responses Re: rsync and streaming replication
List pgsql-admin
On Nov 15, 2011, at 3:02 AM, Cédric Villemain wrote:

> no, you are wrong.
> -c, --checksum
> "This changes the way rsync checks if the files have been changed and
> are in need of a transfer. Without this option, rsync uses a "quick
> check" that (by default) checks if each file's size and time of last
> modification match between the sender and receiver. This option
> changes this to compare a 128-bit checksum for each file that has a
> matching size. Generating the checksums means that both sides will
> expend a lot of disk I/O reading all the data in the files in the
> transfer (and this is prior to any reading that will be done to
> transfer changed files), so this can slow things down significantly. "

Seriously, read that and what I said. They are the same, except that the documentation provides more detail.

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





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