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Old 2009-02-14, 22:35   #1
Smegheads
 

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Default Core i7 - No LL tests due to 256k cache?

Sorry if this has been discussed before, I searched and failed to find it.

My shiny new Core i7 is much faster than my old Athlon X2 4600. 3 or 4 times faster I would guess, when working an exponent in the 46million range transferred from my old computer.

But, because the Core i7 has 256k L2 cache per core, automatic work assignments are limited to exponents < 20million for LL tests, and trial factoring.

So Prime95 is trying to keep the hard work away from slower old processors by testing the L2 cache size, and instead is keeping the hard work away from one of the best CPU's currently available.

Will this be fixed in 25.9?
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Old 2009-02-15, 05:01   #2
CADavis
 
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I think it counts L2+L3 so it should be OK

from http://www.mersenne.org/thresholds/ :

Quote:
Maximum exponent assigned to CPUs with 256KB or less L2+L3 cache 20,000,000
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Old 2009-02-15, 07:25   #3
cheesehead
 
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Quote:
Originally Posted by Smegheads View Post
So Prime95 is trying to keep < snip >

Will this be fixed in 25.9?
As you've probably already noticed on http://www.mersenne.org/thresholds/, assignment thresholds are set in the server, so adjustments will require no client update (but probably do require that project leader George Woltman return from vacation early next month).

Last fiddled with by cheesehead on 2009-02-15 at 07:39
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Old 2009-02-15, 07:51   #4
S485122
 
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Sep 2006
Brussels, Belgium

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I suppose you are already running 25.9.3.
Did you look in the menu Options / CPU at the characteristics as computed by Prime95 ? The L1, L2 and L3 cache should be mentioned there.

Jacob
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Old 2009-02-18, 04:58   #5
eugene2x
 
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Prime95 looks at L2+L3 cache so it shouldn't be a problem, especially considering that the i7 has a whole 8 MB of L3 cache.
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Old 2009-03-27, 08:38   #6
Freightyard
 
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Can anyone explain why my i7 is only receiving TF assignments then?
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Old 2009-04-09, 17:42   #7
ScrappyJoel
 
Mar 2009

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I also would like to know why my Core i7 is assigned Trial Factoring assignments.

I recently upgraded from a Core 2 to a Core i7 and used my old config file. For the two primes I was already running LL test on it continued, but my other two cores got trial factoring test and then when one of my first cores finished their LL test it went on to trial factoring.

I checked my config file and it has '0' as the recommended work setting, which was what it was at previously when my Core 2 was being assigned LL test.

I was going to make a seperate post for this but the guy above me went ahead and asked the question here.
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Old 2009-05-05, 06:57   #8
Freightyard
 
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Seems it fixed itself in the last month!
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Old 2009-05-05, 14:04   #9
Prime95
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Yes. It was a bug in the server assignment code. Another thread reported the problem and I reported it fixed a few weeks ago. I guess I missed this thread.
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