Crunching time - AMD vs Intel
24 Dec 2005 3:03:04 UTC
Topic 190441
(moderation:
I just added another puter to my BOINC farm, a IBM NetVista, Intel P4 Willamette 1.8GHz with SSE2 and 256Meg of 133MHz memory and W2K Pro.
My other big gun is a home built Biostar MOBO with an AMD Sempron Thoroughbred 2800+ running at 2.0GHz with SSE and 1 Gig of 166MHz memory and W2K Pro.
I am running SETI and Einstein on both units.
Both boxes are running optimized BOINC 5.31 clients (edit)
The NetVista is using the YAOSCW-N-8.1 optimized SETI app and the standard Einstein 4.79 app.
949 MIPS Whetstone
3165 MIPS Dhrystone
The Biostar is using the YAOSCW-K-8.1 optimized SETI app and the standard Einstein 4.79 app.
1482 MIPS Whetstone
5448 MIPS Dhrystone
The Biostar box does a SETI unit in about 2:20 and a Einstein unit in about 6:30.
The NetVista box does a SETI unit in about 2:50 and a Einstein unit in about 13:20.
I've heard that AMD's run better on Einstein than Intel's, but double the time for only a 200 MHz drop in CPU speed?
Sorry for the large post. Just wanted to give as much info as possible.
Any comments would be appreciated.
Thanks, Ron K.
Crunching time - AMD vs Intel
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AMD does more work per clockcycle than P4's (I'm not including HT into this.)
That's why AMD started using the + rating on its processors.So the diffrence
is bigger than what the MHz's say.
But I have a feeling that the cpu cache-sizes does play a roll in this.
For ex. Seti runs faster on your P4 because it fits inside the cache.
How big are they?
Hmm, Well, sure
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Hmm, Well, sure ...
Differences,
1) memory clock speed
2) Memory size
3) Dual channel vs. single (?)
4) cache size
Not sure about #4, just realized the cache size is borken across the board and reports everything as 1M now adays.
But, you have 33 MHz difference in memory speed, one has 4 times as much memory as the other and so may not be paging to virtual memory (disk), and the 1G *MAY* be, if in 2 sticks enabling dual channel which by ITSELF doubles bandwidth.
Lastly, not sure, but the 2800 may have 512K cache and that doubles available space. All in all, not a completely unreasonable differrence ...
Oh, yes, also the clock speed ... :)
RE: AMD does more work per
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No HT in the P4 box.
AMD box L1 cache - 2 x 64KB (data & instructions) 2 way
AMD box L2 cache - 256KB 16 way
AMD box bus width - 64 bits
P4 box L1 cache - 8KB data 4 way, 12Kuops trace 8 way
P4 box L2 cache - 256KB 8 way
P4 box bus width - 256 bits
Paul, the AMD box is capable of dual channel memory, but I am only using single channel. Long story short - I was using dual channel until I did a flash BIOS update and the dual channel started crashing my system.
AMD memory - 2 sticks of 512KB (not configured as dual channel)
P4 memory - 2 sticks of 128KB
Is it possible that the optimized SETI apps are keeping those times fairly close while the normal Einstein app just magnifies the difference between the two boxes?
RE: Long story short - I
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Ouch,maybe you should flash it back to the old one again. ;)
Hmm,If the P4 uses SSE2 code and the AMD one only SSE you could be on to something.:)
Was checking my own "standard" seti-crunchers if I saw any trend,but my
list is too small and way too much spread in times to make any conclusions. :P
BTW,My statement that Seti fits inside the cache was wrongly written,sorry.I see it now.. :P
I don't know if it fits in there,my intention was that the app could store more info in cache so it don't have to communicate so often with RAM.
(and I maybe learned more english.. )
Too hard to tell from here
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Too hard to tell from here ...
But, you still have slower memory on the one system, and less of it. Einstein@Home has a large work unit. So, you could be getting killed with swapping to disk. is you disk light on more than a "flash" now and then?
RE: RE: Long story short
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Tried without success. So I now have a stick of 512MB 166MHz memory I can't use. BTW, before you ask, it won't fit in the P4 box. I think it was designed for a max memory of 512MB so the lockout tabs in the slots won't let me plug it in :(.
Paul, I think you are on to something. I notice that the HDD led flashes a lot more often in the P4 box than the AMD box. Do you think that more memory could help?
Quick question, is the L1 & L2 cache in the CPU chip or on the MoBo?
I doubt that einstein data
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I doubt that einstein data would fill up 256MB of RAM though.
Wouldn't some other non-needed application be moved out to swap-space
instead?. (At least I thought Windows worked that way.. but who knows ;)
Edit: Woops,guess I was wrong.Saw your answer after posting this.
L1 and L2 are all inside CPUs these days.
Edit 2:All my farm-boxes(Boinc-only) have 256MB and have at least 130 MB free physical mem while running Einstein.
Quick question too: Does this box only do Boinc or is it used for "everyday use"?
RE: Does this box only do
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P4 box is a dedicated BOINC cruncher. I use the AMD box for my everyday use at home.
I am averaging about 100MB free memory running Einstein.
If I add another 256Meg of memory, would that be enough to use a ram drive to run BOINC in? Would it be any faster?
I can't tell. My harddrives
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I can't tell. My harddrives doesn't run that often,maybe once per hour to save
data.I always have to wait for the harddrive to spin up when I connect to it via RealVNC.
BTW.Closing services of no use saves little memory too.
After an XP installation I almost close half of them.
I don't use defrag automatic on my farmboxes and so on..
For reference: My P4 1.3 GHz crunch Einsteins in under 18 hours and my P4 1.6 in 15 hours.My AMD (o/c +1800 1.54GHz) does them in 8,5 hour.
ps.MAN, you claim a lot of credits with this 5.3.1.. ;)
I *THINK* so. :) See,
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I *THINK* so. :)
See, without careful examination I cannot guarentee anything. And it has been so long since I ran with less than a gig of RAM that I would not be able to say for sure what would be expected.
Windows, in my opinion, does not do a very good job of system management. Including memory management. I *DO* know that when the second generation NT OS came out I was using a minimum of 512K ...
IF the hard drive light is on more on the slower system, then that tells me that it is paging to hard disk. Why or what it is paging is only of interest if you can isolate what is consuming RAM. If you CAN, start turning off things that are running that are not needed (what these might be I have not a clue as MS does not like to tell you what processes are in which named execuatable, and worse, wants to run things that are not needed).
I know there are guides on what items can be removed, but I did the lazy man and just bought more RAM.