On Wed, 2008-07-23 at 21:38 +0300, Heikki Linnakangas wrote: > Simon Riggs wrote: > > On Tue, 2008-07-22 at 17:19 -0700, Martin Zaun wrote: > >> 8. Unresolved question of implementing now/later a "cp" replacement > > > > The patch implements what's been agreed. > > > > I'm not rewriting "cp", for reasons already discussed. > > > > Not a comment to you Martin, but it's fairly clear that I'm not > > maintaining this correctly for Windows. I've never claimed to have > > tested this on Windows, and only included Windows related items as > > requested by others. I need to make it clear that I'm not going to > > maintain it at all, for Windows. If others wish to report Windows issues > > then they can suggest appropriate fixes and test them also. > > Hmm. I just realized that replacing the "cp" command within pg_standby > won't help at all. The problem is with the command that copies the files > *to* the archivelocation that pg_standby polls, not with the copy > pg_standby does from archivelocation to pg_xlog. And we don't have much > control over that. > > We really need a more reliable way of detecting that a file has been > fully copied. One simple improvement would be to check the xlp_magic > field of the last page, though it still wouldn't be bullet-proof. > > Do the commands that preallocate the space keep the file exclusively > locked during the copy? If they do, shouldn't we get an error in trying > to run the restore copy command, and retry after the 1s sleep in > RestoreWALFileForRecovery? Though if the archive location is a samba > mount or something, I guess we can't rely on Windows-style exclusive > locking.
With respect, I need to refer you back to the my last paragraph above. -- Simon Riggs www.2ndQuadrant.com PostgreSQL Training, Services and Support -- Sent via pgsql-patches mailing list (pgsql-patches@postgresql.org) To make changes to your subscription: http://www.postgresql.org/mailpref/pgsql-patches
