On Fri, May 15, 2015 at 1:09 PM, Tom Lane <t...@sss.pgh.pa.us> wrote: > Robert Haas <robertmh...@gmail.com> writes: >> WALWriteLock contention is measurable on some workloads. In studying >> the problem briefly, a couple of questions emerged: > >> 1. Doesn't it suck to rewrite an entire 8kB block every time, instead >> of only the new bytes (and maybe a few bytes following that to spoil >> any old data that might be there)? > > It does, but it's not clear how to avoid torn-write conditions without > that.
Can you elaborate? I don't understand how repeatedly overwriting the same bytes with themselves accomplishes anything at all. -- Robert Haas EnterpriseDB: http://www.enterprisedb.com The Enterprise PostgreSQL Company -- Sent via pgsql-hackers mailing list (pgsql-hackers@postgresql.org) To make changes to your subscription: http://www.postgresql.org/mailpref/pgsql-hackers
