On Tue, Oct 19, 2010 at 10:36 AM, Tom Lane <tgl@xxxxxxxxxxxxx> wrote: > Jon Nelson <jnelson+pgsql@xxxxxxxxxxx> writes: >> This is another situation where using pread would have saved a lot of >> time and sped things up a bit, but failing that, keeping track of the >> file position ourselves and only lseek'ing when necessary would also >> help. > > No, it wouldn't; you don't have the slightest idea what's going on > there. Those lseeks are for the purpose of detecting the current EOF > location, ie, finding out whether some other backend has extended the > file recently. We could get rid of them, but only at the cost of > putting in some other communication mechanism instead. I don't get it. Why would be doing that in a tight loop within a single backend? -- Robert Haas EnterpriseDB: http://www.enterprisedb.com The Enterprise PostgreSQL Company -- Sent via pgsql-performance mailing list (pgsql-performance@xxxxxxxxxxxxxx) To make changes to your subscription: http://www.postgresql.org/mailpref/pgsql-performance
