Nope - it would be disk wait. COPY is CPU bound on I/O subsystems faster that 50 MB/s on COPY (in) and about 15 MB/s (out).
- Luke -----Original Message----- From: Michael Stone [mailto:[EMAIL PROTECTED] Sent: Wed Oct 05 09:58:41 2005 To: Martijn van Oosterhout Cc: pgsql-hackers@postgresql.org; pgsql-performance@postgresql.org Subject: Re: [HACKERS] [PERFORM] A Better External Sort? On Sat, Oct 01, 2005 at 06:19:41PM +0200, Martijn van Oosterhout wrote: >COPY TO /dev/null WITH binary >13MB/s 55% user 45% system (ergo, CPU bound) [snip] >the most expensive. But it does point out that the whole process is >probably CPU bound more than anything else. Note that 45% of that cpu usage is system--which is where IO overhead would end up being counted. Until you profile where you system time is going it's premature to say it isn't an IO problem. Mike Stone ---------------------------(end of broadcast)--------------------------- TIP 2: Don't 'kill -9' the postmaster ---------------------------(end of broadcast)--------------------------- TIP 3: Have you checked our extensive FAQ? http://www.postgresql.org/docs/faq
