On Sat, Apr 7, 2018 at 6:26 AM, Andres Freund <and...@anarazel.de> wrote:
> On 2018-04-06 17:59:28 -0700, Andres Freund wrote: > > + /* > > + * Create a database list. We don't need to concern ourselves with > > + * rebuilding this list during runtime since any database created > after > > + * this process started will be running with checksums turned on > from the > > + * start. > > + */ > > > > Why is this true? What if somebody runs CREATE DATABASE while the > > launcher / worker are processing a different database? It'll copy the > > template database on the filesystem level, and it very well might not > > yet have checksums set? Afaict the second time we go through this list > > that's not cought. > > *caught > > It's indeed trivial to reproduce this, just slowing down a checksum run > and copying the database yields: > ./pg_verify_checksums -D /srv/dev/pgdev-dev > pg_verify_checksums: checksum verification failed in file > "/srv/dev/pgdev-dev/base/16385/2703", block 0: calculated checksum 45A7 > but expected 0 > pg_verify_checksums: checksum verification failed in file > "/srv/dev/pgdev-dev/base/16385/2703", block 1: calculated checksum 8C7D > but expected 0 > > > > further complaints: > > The new isolation test cannot be re-run on an existing cluster. That's > because the first test expects isolationtests to be disabled. As even > remarked upon: > # The checksum_enable suite will enable checksums for the cluster so should > # not run before anything expecting the cluster to have checksums turned > off > > How's that ok? You can leave database wide objects around, but the > cluster-wide stuff needs to be cleaned up. > > > The tests don't actually make sure that no checksum launcher / apply is > running anymore. They just assume that it's gone once the GUC shows > checksums have been set. If you wanted to make the tests stable, you'd > need to wait for that to show true *and* then check that no workers are > around anymore. > > > If it's not obvious: This isn't ready, should be reverted, cleaned up, > and re-submitted for v12. > While I do think that it's still definitely fixable in time for 11, I won't argue for it.Will revert. Note however that I'm sans-laptop until Sunday, so I will revert it then or possibly Monday. -- Magnus Hagander Me: https://www.hagander.net/ <http://www.hagander.net/> Work: https://www.redpill-linpro.com/ <http://www.redpill-linpro.com/>
