Re: Enabling Checksums

Jeff Davis <pgsql@j-davis.com>

From: Jeff Davis <pgsql@j-davis.com>
To: Simon Riggs <simon@2ndQuadrant.com>
Cc: Robert Haas <robertmhaas@gmail.com>, Pavel Stehule <pavel.stehule@gmail.com>, Josh Berkus <josh@agliodbs.com>, pgsql-hackers@postgresql.org
Date: 2012-12-04T09:03:36Z
Lists: pgsql-hackers

Attachments

On Mon, 2012-12-03 at 09:56 +0000, Simon Riggs wrote:
> 1. Break out the changes around inCommit flag, since that is just
> uncontroversial refactoring. I can do that. That reduces the noise
> level in the patch and makes it easier to understand the meaningful
> changes.

Done by you.

> 2. Produce an SGML docs page that describes how this works, what the
> limitations and tradeoffs are. "Reliability & the WAL" could use an
> extra section2 header called Checksums (wal.sgml). This is essential
> for users AND reviewers to ensure everybody has understood this (heck,
> I can't remember everything about this either...)

Agreed. It looks like it would fit best under the Reliability section,
because it's not directly related to WAL. I'll write something up.

> 3. I think we need an explicit test of this feature (as you describe
> above), rather than manual testing. corruptiontester?

I agree, but I'm not 100% sure how to proceed. I'll look at Kevin's
tests for SSI and see if I can do something similar, but suggestions are
welcome. A few days away, at the earliest.

> 4. We need some general performance testing to show whether this is
> insane or not.

My understanding is that Greg Smith is already working on tests here, so
I will wait for his results.

> But this looks in good shape for commit otherwise.

Great!

For now, I rebased the patches against master, and did some very minor
cleanup.

Regards,
	Jeff Davis