Andreas Pflug <[EMAIL PROTECTED]> writes: > Tom Lane wrote: >> As far as the question "can PG do 1-2k xact/sec", the answer is "yes >> if you throw enough hardware at it". Spending enough money on the >> disk subsystem is the key ... >> > The 1-2k xact/sec for MySQL seems suspicious, sounds very much like > write-back cached, not write-through, esp. considering that heavy > concurrent write access isn't said to be MySQLs strength...
> I wonder if preserving the database after a fatal crash is really > necessary, since the data stored sounds quite volatile; in this case, > fsync=false might be sufficient. Yeah, that's something to think about. If you do need full transaction safety, then you *must* have a decent battery-backed-write-cache setup, else your transaction commit rate will be limited by disk rotation speed --- for instance, a single connection can commit at most 250 xacts per second if the WAL log is on a 15000RPM drive. (You can improve this to the extent that you can spread activity across multiple connections, but I'm not sure you can expect to reliably have 8 or more connections ready to commit each time the disk goes 'round.) regards, tom lane ---------------------------(end of broadcast)--------------------------- TIP 2: Don't 'kill -9' the postmaster