On Mon, Feb 8, 2016 at 11:24 PM, Amit Kapila <amit.kapil...@gmail.com> wrote: > On Mon, Feb 8, 2016 at 12:28 PM, Michael Paquier <michael.paqu...@gmail.com> > wrote: >> >> >> >> /* >> >> + * Fetch the progress position before taking any WAL insert lock. >> >> This >> >> + * is normally an operation that does not take long, but leaving >> >> this >> >> + * lookup out of the section taken an exclusive lock saves a >> >> couple >> >> + * of instructions. >> >> + */ >> >> + progress_lsn = GetProgressRecPtr(); >> > >> > too long for my taste. How about: >> > /* get progress, before acuiring insert locks to shorten locked section >> > */ >> >> Check. >> > > What is the need of holding locks one-by-one during checkpoint when > we anyway are going to take lock on all the insertion slots.
A couple of records can slip in while scanning the progress LSN through all the locks. > + * to not rely on taking an exclusive lock an all the WAL insertion locks, > > /an all/on all Nice catch. -- Michael -- Sent via pgsql-hackers mailing list (pgsql-hackers@postgresql.org) To make changes to your subscription: http://www.postgresql.org/mailpref/pgsql-hackers
