On Fri, May 04, 2007 at 12:33:29AM -0400, Greg Smith wrote:
-bash-3.00$ psql
postgres=# \timing
Timing is on.
postgres=# select count(*) from generate_series(1,100000,1);
count
--------
100000
(1 row)
Time: 106.535 ms
There you go, a completely cross-platform answer. You should run the
statement twice and only use the second result for better consistancy. I
ran this on all the sytems I was around today and got these results:
P4 2.4GHz 107ms
Xeon 3GHz 100ms
Opteron 275 65ms
Athlon X2 4600 61ms
PIII 1GHz 265ms
Opteron 250 39ms
something seems inconsistent here.
For comparison sake, these numbers are more useful at predicting actual
application performance than Linux's bogomips number, which completely
reverses the relative performance of the Intel vs. AMD chips in this set
from the reality of how well they run Postgres.
You misunderstand the purpose of bogomips; they have no absolute
meaning, and a comparison between different type of cpus is not
possible.
While I'm ranting here, I should mention that I also sigh every time I see
people suggest we should ask the user how big their database is. The kind
of newbie user people keep talking about helping has *no idea whatsoever*
how big the data actually is after it gets into the database and all the
indexes are built.
100% agreed.
Mike Stone
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