pgsql: Update item description: * Consider having the background writer

On Mon, 2007-12-17 at 01:40 +0000, Bruce Momjian wrote:

Log Message:
-----------
Update item description:

* Consider having the background writer update the transaction status
hint bits before writing out the page

Implementing this requires the background writer to have access to system
catalogs and the transaction status log.

Not very sure why you've added this one to the TODO list?

I raised it as not-a-good idea and I think Tom and Alvaro agreed. i.e. I
mentioned it in order to kill it. It's a ton of work for what very well
might be overhead rather than gain.

--
Simon Riggs
2ndQuadrant http://www.2ndQuadrant.com

Simon Riggs wrote:

On Mon, 2007-12-17 at 01:40 +0000, Bruce Momjian wrote:

Log Message:
-----------
Update item description:

* Consider having the background writer update the transaction status
hint bits before writing out the page

Implementing this requires the background writer to have access to system
catalogs and the transaction status log.

Not very sure why you've added this one to the TODO list?

I raised it as not-a-good idea and I think Tom and Alvaro agreed. i.e. I
mentioned it in order to kill it. It's a ton of work for what very well
might be overhead rather than gain.

I actually do feel it might be valuable. All our opinions are based on
gut-feeling, though, so would need benchmarking to see if it's really
worth it or not.

I think we could get away without accessing system catalogs in bgwriter,
if we flagged heap pages as such in ReadBuffer. Just a thought..

--
Heikki Linnakangas
EnterpriseDB http://www.enterprisedb.com

On Mon, 2007-12-17 at 22:46 +0000, Heikki Linnakangas wrote:

I actually do feel it might be valuable. All our opinions are based on
gut-feeling, though, so would need benchmarking to see if it's really
worth it or not.

I think we could get away without accessing system catalogs in bgwriter,
if we flagged heap pages as such in ReadBuffer. Just a thought..

Well, if you or Bruce or anybody else thinks it should be on the TODO
then a case should be made for it. I have no doubt you could write it,
but the point is why would you? Or why would you want somebody else to
if you're not going to?

Everybody that spoke on the original thread was against it and I
specifically mentioned it to kill the idea. Its just plain weird that
multiple people have given arguments as to why its a bad idea and yet it
goes straight onto the TODO. LOL.

If that criteria is used to add stuff to the TODO then it would be
bursting with crappy ideas...

--
Simon Riggs
2ndQuadrant http://www.2ndQuadrant.com

Simon Riggs wrote:

On Mon, 2007-12-17 at 22:46 +0000, Heikki Linnakangas wrote:

I actually do feel it might be valuable. All our opinions are based on
gut-feeling, though, so would need benchmarking to see if it's really
worth it or not.

I think we could get away without accessing system catalogs in bgwriter,
if we flagged heap pages as such in ReadBuffer. Just a thought..

Well, if you or Bruce or anybody else thinks it should be on the TODO
then a case should be made for it. I have no doubt you could write it,
but the point is why would you? Or why would you want somebody else to
if you're not going to?

Everybody that spoke on the original thread was against it and I
specifically mentioned it to kill the idea. Its just plain weird that
multiple people have given arguments as to why its a bad idea and yet it
goes straight onto the TODO. LOL.

If that criteria is used to add stuff to the TODO then it would be
bursting with crappy ideas...

I saw people saying it could be complex, not that it was a bad idea, and
I just added a description --- the idea was already on the TODO list.

--
Bruce Momjian <bruce@momjian.us> http://momjian.us
EnterpriseDB http://postgres.enterprisedb.com

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