On Wed, Dec 30, 2020 at 12:52:46PM -0800, Andres Freund wrote: > Hi, > > A question from a colleague made me wonder if there are scenarios where > two subsequent crashes could lead to wrong WAL to be applied. > > Imagine the following scenario > [ xlog page 1 ][ xlog page 2 ][ xlog page 3 ][ xlog page 4 ] > ^flush ^write ^insert > > if the machine crashes in this moment, we could end up with a situation > where page 1, 3, 4 made it out out to disk, but page 2 wasn't.
I don't see any flaw in your logic. Seems we have to zero out all future WAL files, not just to the end of the current one, or at least clear xlp_pageaddr on each future page. -- Bruce Momjian <br...@momjian.us> https://momjian.us EnterpriseDB https://enterprisedb.com The usefulness of a cup is in its emptiness, Bruce Lee
