View Single Post
Old 2010-04-15, 10:01   #7
garo
 
garo's Avatar
 
Aug 2002
Termonfeckin, IE

53148 Posts
Default

lycorn has made a reasonable suggestion. It might be overkill to set all 6 cores to do P-1 - though there is no reason not to particularly since we are always short of P-1 testers. 300MB is a good amount for 53M tests that are being done today. 500MB is better. After that the marginal gains with every extra MB of RAM get smaller. George's recommendation from the readme.txt is
50000000 85MB 170MB 250MB
for a 50M the min, reasonable and desirable memory.

Also since the max memory is only used during stage 2, you can limit the number of threads that do stage 2 at any one time.
MaxHighMemWorkers=n
This will stagger your stage 2s and when the number of workers doing stage 2 reaches the limit, additional workers will skip stage 2 and do stage 1 on subsequent exponents before returning to do stage 2 when the memory becomes free. If six cores are doing P-1, you could get by with setting MaxHighMemWorkers=4 and still achieve maximal throughput. So you really could get by with only 1GB of RAM and 6 P-1s if you needed to.

If you do real work with the computer during the day you may want to set different amounts of memory available to the computer during the day and night. And set Prime95 to only do stage2 when max memory is available with this switch:
OnlyRunStage2WithMaxMemory=1

Last fiddled with by garo on 2010-04-15 at 10:03
garo is offline   Reply With Quote