Just curious to see if anyone has changed settings on their APU to use more of the system memory for crunching performance. My 2200G by default has 2.0 GB allocated for the GPU. I'm using between 1.5 and 1.7 GB of that, and I can't help but wonder if that is slowing GPU performance. Currently using 70%/90% of memory, but I assume that is for system memory, not for GPU (whether discrete or not) memory? I have 16 GB total, so no issue with allocating a couple more GB. I'll probably play around with it after WOW is over.

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Seti@home classic: 1,456 results, 1.613 years CPU time

Just curious to see if anyone has changed settings on their APU to use more of the system memory for crunching performance. My 2200G by default has 2.0 GB allocated for the GPU. I'm using between 1.5 and 1.7 GB of that, and I can't help but wonder if that is slowing GPU performance. Currently using 70%/90% of memory, but I assume that is for system memory, not for GPU (whether discrete or not) memory? I have 16 GB total, so no issue with allocating a couple more GB. I'll probably play around with it after WOW is over.

When I tried less than 2GB the windows taskmanager started reporting it was using "main memory" too. I don't remember if I ran it long enough to see if it changed the performance.

Tom

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A proud member of the OFA (Old Farts Association).

after taking a look at some stderr.txt you could modify your command line options

with -period_iterations_num 4 you could add -tt 1500 to speed up your FFT routine here

Fftlength=8,pass=3:Tune: sum=16775.1(ms); min=0.00288(ms); max=505.4(ms); mean=78.76(ms); s_mean=84.41; sleep=75(ms); delta=5; N=213; usual
Fftlength=8,pass=4:Tune: sum=8758.26(ms); min=0.00288(ms); max=283.4(ms); mean=71.79(ms); s_mean=46.18; sleep=45(ms); delta=7; N=122; usual
Fftlength=8,pass=5:Tune: sum=4890.09(ms); min=0.00288(ms); max=163.4(ms); mean=65.2(ms); s_mean=56.68; sleep=45(ms); delta=202; N=75; usual
Fftlength=16,pass=3:Tune: sum=8655.57(ms); min=2.107(ms); max=118.8(ms); mean=61.39(ms); s_mean=51.86; sleep=45(ms); delta=211; N=141; usual
Fftlength=16,pass=4:Tune: sum=5605.09(ms); min=2.838(ms); max=80.53(ms); mean=60.92(ms); s_mean=59.06; sleep=60(ms); delta=276; N=92; usual
Fftlength=16,pass=5:Tune: sum=4018.42(ms); min=2.92(ms); max=83.98(ms); mean=59.09(ms); s_mean=52.64; sleep=45(ms); delta=357; N=68; usual
Fftlength=32,pass=3:Tune: sum=8173.22(ms); min=0.923(ms); max=102.7(ms); mean=59.66(ms); s_mean=56.81; sleep=45(ms); delta=281; N=137; usual
Fftlength=32,pass=4:Tune: sum=5486.69(ms); min=2.882(ms); max=82.95(ms); mean=54.32(ms); s_mean=54.97; sleep=45(ms); delta=338; N=101; usual
Fftlength=32,pass=5:Tune: sum=4079.76(ms); min=0.6144(ms); max=95.38(ms); mean=47.44(ms); s_mean=46.6; sleep=45(ms); delta=475; N=86; usual
Fftlength=64,pass=3:Tune: sum=8425.46(ms); min=0.4523(ms); max=103.1(ms); mean=52.01(ms); s_mean=44.23; sleep=45(ms); delta=305; N=162; usual
Fftlength=64,pass=4:Tune: sum=5814.48(ms); min=0.444(ms); max=68.55(ms); mean=46.52(ms); s_mean=60.01; sleep=60(ms); delta=309; N=125; usual
Fftlength=64,pass=5:Tune: sum=4343.75(ms); min=0.9982(ms); max=51.84(ms); mean=35.9(ms); s_mean=44.43; sleep=45(ms); delta=542; N=121; usual
Fftlength=128,pass=3:Tune: sum=20329.7(ms); min=92.53(ms); max=120.1(ms); mean=107.6(ms); s_mean=104.8; sleep=105(ms); delta=1; N=189; usual
Fftlength=256,pass=3:Tune: sum=24707.1(ms); min=30.16(ms); max=75.43(ms); mean=65.19(ms); s_mean=65.73; sleep=60(ms); delta=1; N=379; usual
Fftlength=512,pass=3:Tune: sum=26651.3(ms); min=15.65(ms); max=65.99(ms); mean=35.11(ms); s_mean=40.29; sleep=30(ms); delta=1; N=759; usual
Fftlength=1024,pass=3:Tune: sum=8220.21(ms); min=5.045(ms); max=6.86(ms); mean=5.419(ms); s_mean=5.576; sleep=0(ms); delta=1; N=1517; usual
Fftlength=2048,pass=3:Tune: sum=5202.03(ms); min=1.399(ms); max=3.792(ms); mean=1.715(ms); s_mean=1.782; sleep=0(ms); delta=1; N=3033; usual

at FFTlength 8 to 1024 u must see some improvement with only one line of pass=3 and high_perf if not u have to set a higher number at -tt

Fftlength=8,pass=3:Tune: sum=16775.1(ms); min=0.00288(ms); max=505.4(ms); mean=78.76(ms); s_mean=84.41; sleep=75(ms); delta=5; N=213; usual => 213 * 78.76 ~= sum time
Fftlength=8,pass=4:Tune: sum=8758.26(ms); min=0.00288(ms); max=283.4(ms); mean=71.79(ms); s_mean=46.18; sleep=45(ms); delta=7; N=122; usual => 122 * 71.79 ~= 8758,38 ~ sum time
Fftlength=8,pass=5:Tune: sum=4890.09(ms); min=0.00288(ms); max=163.4(ms); mean=65.2(ms); s_mean=56.68; sleep=45(ms); delta=202; N=75; usual => 75 * 65.2 ~= sum time

all Fftlength=8 are done in 16775 +8758+ 4890 = 30sec 213 in 3 pass ( best opt) 122 in 4 pass and 75 in 5 pass

the -tt 1500 give more time to do all Fftlength=8 in only 3 pass .

to see the long therm improvement, just take a look at your app details

https://setiathome.berkeley.edu/host_app_versions.php?hostid=8640304

SETI@home v8 8.22 windows_intelx86 (opencl_ati5_SoG_nocal)
Taux de calcul moyen 46.96 GFLOPS

SETI@home v8 8.22 windows_intelx86 (opencl_ati_nocal)
Taux de calcul moyen 42.77 GFLOPS

the estimated Gflops will become better after ^^

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So after looking at the UMA buffer size in my bios, the maximum it can be set to is 2 GB, so I guess I'm stuck with that.

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Seti@home classic: 1,456 results, 1.613 years CPU time

Correction! There was another way in the bios to set the APU dedicated GPU memory. I found a way to increase it to 3 GB. It can go higher, but there is some problem either with the bios or how I'm changing settings that is preventing me from going higher. I'll have to work that out with ASRock. Regardless, I now have 3 GB, and at times I am using 2.6 GB. Of course, in the interim I have changed S@H to run 2 GPU tasks on the APU at a time, so I am sure that is part of the reason. I am probably changing too many settings at once to know what is actually improving performance, so we'll have to see eventually. I just wanted to report memory allocation can be increased.

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Seti@home classic: 1,456 results, 1.613 years CPU time

Everyones computer is different but I have played around with this setting and tried everything from 64 to 2048 and on my system at least there is no difference using anything higher then 256 for my apu's gpu so long as I run up to a max of 1 multibeam and 1 astropulse task at a time.