Re: TOAST performance (was Re: [GENERAL] Delete Perform
If "pre-page WAL write" means the value of the page before the current
changes, then there is generally another reason for writing it out.
Bruce, "*pre*-page" is confusing - we write "after-change" page
image to WAL.
When the system comes back up, we need to do a rollback on
transaction B since it did not commit and we need the "pre-page"
to know how to undo the change for B that got saved in step 6 above.
Brian, PGSQL still uses non-overwriting storage manager -
removing rows inserted by aborted transactions is not required.
Vadim
If "pre-page WAL write" means the value of the page before the current
changes, then there is generally another reason for writing it out.Bruce, "*pre*-page" is confusing - we write "after-change" page
image to WAL.
Yes, I didn't like pre-page either. Changed.
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