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Astropulse app install problem

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MasterChief:
The MP Xeons in the server have 512kb L1 & 2mb L2 to old for L3. SSE2

They seem to be doing pretty well all things considered.

Currently have 8 AP tasks running. Going by average cpu time vs percentage...looks like about a 50hr +/- average.

Here's a breakdown on the server: http://stats.free-dc.org/stats.php?page=hostbycpid&cpid=18a9195a188b97c8c587efd7df35149e

Raistmer:

--- Quote from: MasterChief on 19 Oct 2009, 07:18:15 pm ---The MP Xeons in the server have 512kb L1 & 2mb L2 to old for L3. SSE2

--- End quote ---
512kB of L1 cache ?!  :o  :o  :o
It's just HUGE, it's more than L2 cache for most P4  :o

MasterChief:
Er...my bad! ::)

I must be getting old...my mind is slipping some. ;)

L1 is 8kb, L2 is 512kb, and L3 is 2mb. L1 & L2 are 8-way associative. MMX, SSE, and SSE2

Seems my completetime estimates were way off to! Looking more like 80 to 90hrs per AP task? Isn't that a little slow? I've seen times for more modern cpu's that are in the 40hr or less range? Or are those GPU times?

Echternacht mentioned that running to many at once can degrade performance? Have 8 AP's running at present time on four cpu's. Do I need to cut that number down? And if so...how much? Or should I just go back to running regular seti tasks?

Raistmer:
General rule - try to run different tasks on adjacent cores.
If L2 is cache per core - run no more 1 AP on each core. If L2 per 2 cores - run 1 AP task per 2 cores and add some MB tasks in mix.
Unfortunately I don't know way to do it with current BOINC versions.
Project/app pairing is missing feature....
For example, 32k of complex floats - it's FFT size used by AP.
It will take 32*2*4=256k of memory. General rule - not to take more than 1/2 of cache lines for app to avoid cache line excessive evictions. Thats why P4 should not like AP tasks and Xeon can handle 1 per core better than P4.
6MB per 2 cores of quads is just perfect for AP tasks. P4 will be better with MB tasks IMO.

sunu:
A bit late at the party...

Ubuntu repositories have a fairly old boinc version. At http://boinc.berkeley.edu/download_all.php you can find newer versions. With these you can install boinc in your home directory, no need for correct permissions or other stuff. Boinc needs a lot of tinkering, so being in your home directory is better since you don't have to be root.

Astropulse is quite a bit faster in 64 bit. If you could go 64bit you would see a speedup compared to your 32bit.

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