Re: WAL documentation changes

Michael Renner wrote:
> Hi,
>
> the comment WRT WAL recovery and FS journals [1] is a bit misleading in
> it's current form.
>
> First, none of the general purpose filesystems I've seen so far do data
> journalling per default, since it's a huge performance penalty, even for
> non-RDBMS workloads. The feature you talk about is ext3 specific (and
> should be pointed out as such) and only disables write ordering, meaning
> that metadata and file content updates are not synchronized.

You are right that my docs were misleading. I have improved them by
mentioning that it is _data_ flush that as part of journalling that can
be a problem, and documented that the mount option listed is
ext3-specific, not linux-specific.

Updated docs attached. Please let me know if I can improve it some
more.

--
Bruce Momjian <bruce(at)momjian(dot)us> http://momjian.us
EnterpriseDB http://enterprisedb.com

+ If your life is a hard drive, Christ can be your backup. +