Quad PowerMac slower than iMac G5??
20 Nov 2005 14:05:16 UTC
Topic 190188
(moderation:
How is this possible?
For comparsion:
http://einsteinathome.org/workunit/2655392
Computer ID: 84978
iMac G5 (PowerMac8,1)
CPU: IBM PPC970 2GHz?
CPU time: 21,967.32 sec.
E@H client: ?
Computer ID: 442841
PowerMac Quad G5 (PowerMac11,2)
CPU: IBM PPC970MP
CPU time: 24,996.47 sec.
E@H client: BETA 0.12
Regards
Karl
Quad PowerMac slower than iMac G5??
)
Do your "General preferences" allow all 4 processors to operate (see "On multiprocessors, use at most: X") ?
RE: How is this
)
I don't know the clock speed of the iMac G5 - I assume your Quad is 2.5GHz. You have to realize that each result is only going to use _one_ of your four cores, so the "time per result" is still going to be "x", not "1/4 x". The advantage of the four cores is that you'll turn in four results in that same time period "x" instead of just one. Also, your time "x" is going to be _slightly_ longer if you're running all four cores than it would be if you were running only one, because you'll have four processes competing for the same RAM, disk writes, etc. Since these are true CPU cores and not Intel's "HyperThreading" pretend-cores, you WILL see a huge gain in total throughput - maybe 3.8x not quite 4x - and not the 1.05x HT gives.
I'm puzzled though - looking further, you only show a PowerMac 3,5 (G4) on your account. Is the Quad someone elses?
EDIT:: Nevermind, it's one of your teammates. I note he's running the old Mac BETA Einstein version - he really needs to get rid of that and let it download the standard Altivec-enhanced one, now that it's no longer beta.