On 13-5-2009 20:39 Scott Carey wrote:
Excellent! That is a pretty huge boost. I'm curious which aspects of this new architecture helped the most. For Postgres, the following would seem the most relevant: 1. Shared L3 cache per processors -- more efficient shared datastructure access. 2. Faster atomic operations -- CompareAndSwap, etc are much faster. 3. Faster cache coherency. 4. Lower latency RAM with more overall bandwidth (Opteron style).
Apart from that, it has a newer debian (and thus kernel/glibc) and a slightly less constraining IO which may help as well.
Can you do a quick and dirty memory bandwidth test? (assuming linux) On the older X5355 machine and the newer E5540, try: /sbin/hdparm -T /dev/sd<device>
It is in use, so the results may not be so good, this is the best I got on our dual X5355:
Timing cached reads: 6314 MB in 2.00 seconds = 3159.08 MB/sec But this is the best I got for a (also in use) Dual E5450 we have: Timing cached reads: 13158 MB in 2.00 seconds = 6587.11 MB/sec And here the best for the (idle) E5540: Timing cached reads: 16494 MB in 2.00 seconds = 8256.27 MB/sec These numbers are with hdparm v8.9 Best regards, Arjen -- Sent via pgsql-performance mailing list (pgsql-performance@xxxxxxxxxxxxxx) To make changes to your subscription: http://www.postgresql.org/mailpref/pgsql-performance
