<image redacted> i7-3630qm
Something seems wrong.
It is consistent
arent mobile i7s 2x2 core/thread(2c2t?)? it seems that this also happened to the previous poster who put the hex core amd where the last two results were messed up probably because it doesn't have 8 cores.Something is wrong with mine.
8 thread is 16.7
but only 49%
?
i7-3630qm
Something seems wrong.
It is consistent
I'd be willing to bet power-management is screwing up the 1-thread reading, resulting in way too many CPU cycles being logged to get the job done.
Then when subsequent runs are initiated the power-management gets out of the way, speed goes up but it seems like it is all because of 2-threads now so the scaling goes crazy high.
This can happen when core-parking is allowed. It is an issue with LinX too, even on desktops, when HT is enabled.
Would it be possible to edit that quote? I removed it because there was some stuff showing up in the background that I would prefer not to.
arent mobile i7s 2x2 core/thread(2c2t?)? it seems that this also happened to the previous poster who put the hex core amd where the last two results were messed up probably because it doesn't have 8 cores.
Ran it on my Thuban just for fun:
1 thread(s) 2607641 cpu cycles (100 % of 1 thread). MT scaling factor: 1.00
2 thread(s) 2607693 cpu cycles (100 % of 1 thread). MT scaling factor: 2.00
3 thread(s) 2608526 cpu cycles (100 % of 1 thread). MT scaling factor: 3.00
4 thread(s) 2609853 cpu cycles (100 % of 1 thread). MT scaling factor: 4.00
5 thread(s) 2609338 cpu cycles (100 % of 1 thread). MT scaling factor: 5.00
6 thread(s) 2612983 cpu cycles (100 % of 1 thread). MT scaling factor: 5.99
Thank you everyone for your results, especially JQuilty for the FX-8350 run :thumbsup:
It seems to me that these power management and turbo features influence results much more than anything else, so they should be taken with some reserve. Still, I think this is already an indication that this type of workload might be very well suited for AMD's CMT, and not so much for HT.
1 thread(s) 2249908 cpu cycles (100 % of 1 thread). MT scaling factor: 1.00
2 thread(s) 2277602 cpu cycles (101 % of 1 thread). MT scaling factor: 1.98
3 thread(s) 4536493 cpu cycles (201 % of 1 thread). MT scaling factor: 1.49
4 thread(s) 4561711 cpu cycles (202 % of 1 thread). MT scaling factor: 1.97
5 thread(s) 6827625 cpu cycles (303 % of 1 thread). MT scaling factor: 1.65
6 thread(s) 6851558 cpu cycles (304 % of 1 thread). MT scaling factor: 1.97
7 thread(s) 9059221 cpu cycles (402 % of 1 thread). MT scaling factor: 1.74
8 thread(s) 9140645 cpu cycles (406 % of 1 thread). MT scaling factor: 1.97
1 thread(s) 2255724 cpu cycles (100 % of 1 thread). MT scaling factor: 1.00
2 thread(s) 2278640 cpu cycles (101 % of 1 thread). MT scaling factor: 1.98
3 thread(s) 4556735 cpu cycles (202 % of 1 thread). MT scaling factor: 1.49
4 thread(s) 4591366 cpu cycles (203 % of 1 thread). MT scaling factor: 1.97
5 thread(s) 6808452 cpu cycles (301 % of 1 thread). MT scaling factor: 1.66
6 thread(s) 6829825 cpu cycles (302 % of 1 thread). MT scaling factor: 1.98
7 thread(s) 9079475 cpu cycles (402 % of 1 thread). MT scaling factor: 1.74
8 thread(s) 9124735 cpu cycles (404 % of 1 thread). MT scaling factor: 1.98
One thing that continues to concern me is how much impact the power saving is having on what is quite obviously an "all resources are necessary" problem. The power saving doesn't just work as its meant to, it seems to downclock and park cores at moments where the CPU appears to be fully utilised.
Does disabling parked cores make a difference or is it just about going to max performance that fixes the problem?
This should not be the case, we should consider it a bug and report it as such to Microsoft. Its not correct that the machine is parking itself and leaving large amounts of unused cycles when its clearly fully utilised.
Please note that this particular benchmark does not really represent any real world application, it operates on only 1 MB of random generated data, which fits easily in L3 cache, even L2 cache in FX series. The purpose was to see if HT/CMT cores can be used as pure integer cores without (much) penalty.
Actually, lately I have had quite a few multithreaded development projects and I am trying to decide on which platform to buy for my new workstation. I don't care that much about power consumption, IPC or performance, because it would be fully loaded only for very small fractions of time, so I think any new cpu would be good enough for me -- even my old workstation with Core 2-based dual core Xeon and a fast SSD is still mostly fine. What I need is a many core cpu to be able to simulate and debug concurrency and other threading effects in MT applications. And these are mostly server applications, not something anyone would want to run at home on commodity hardware anyway. I'll take a little more time to decide, but I think I will probably go for either a 4C8T E3-series Xeon or FX-8350.
1 thread(s) 3041928 cpu cycles (100 % of 1 thread). MT scaling factor: 1.00
2 thread(s) 3051962 cpu cycles (100 % of 1 thread). MT scaling factor: 1.99
3 thread(s) 3059131 cpu cycles (100 % of 1 thread). MT scaling factor: 2.98
4 thread(s) 3068054 cpu cycles (100 % of 1 thread). MT scaling factor: 3.97
5 thread(s) 3080683 cpu cycles (101 % of 1 thread). MT scaling factor: 4.94
6 thread(s) 3099179 cpu cycles (101 % of 1 thread). MT scaling factor: 5.89
7 thread(s) 3127752 cpu cycles (102 % of 1 thread). MT scaling factor: 6.81
8 thread(s) 3128746 cpu cycles (102 % of 1 thread). MT scaling factor: 7.78
1 thread(s) 3017522 cpu cycles (100 % of 1 thread). MT scaling factor: 1.00
2 thread(s) 3031920 cpu cycles (100 % of 1 thread). MT scaling factor: 1.99
3 thread(s) 3211052 cpu cycles (106 % of 1 thread). MT scaling factor: 2.82
4 thread(s) 3231453 cpu cycles (107 % of 1 thread). MT scaling factor: 3.74
5 thread(s) 3237524 cpu cycles (107 % of 1 thread). MT scaling factor: 4.66
6 thread(s) 3244135 cpu cycles (107 % of 1 thread). MT scaling factor: 5.58
7 thread(s) 3265295 cpu cycles (108 % of 1 thread). MT scaling factor: 6.47
8 thread(s) 3286271 cpu cycles (108 % of 1 thread). MT scaling factor: 7.35
So it is really no surprise that AMD scales better, after all the 8350 has 8 real integer cores so you should expect nearly 8x the performance.
HT is just using 4 cores with the extra threads beyond 4 taking up otherwise wasted cycles. No way anyone actually expects perfect scaling from HT.
Just for reference, this is for my (new) FX-8320, all *stock* 3.5Ghz frequencies, nothing optimized.
I ran this 5 times and, while some of the intermediate numbers varied a bit, the end 8 thread number was always within +/- 0.03 of the results below
Now two test runs with Power Managment set to "CPU always 100%"F:\Temp>crcbench
1 thread(s) 2592039 cpu cycles (100 % of 1 thread). MT scaling factor: 1.00
2 thread(s) 2592619 cpu cycles (100 % of 1 thread). MT scaling factor: 2.00
3 thread(s) 3165399 cpu cycles (122 % of 1 thread). MT scaling factor: 2.46
4 thread(s) 3281959 cpu cycles (126 % of 1 thread). MT scaling factor: 3.16
5 thread(s) 3145442 cpu cycles (121 % of 1 thread). MT scaling factor: 4.12
6 thread(s) 2914909 cpu cycles (112 % of 1 thread). MT scaling factor: 5.34
7 thread(s) 2866660 cpu cycles (110 % of 1 thread). MT scaling factor: 6.33
8 thread(s) 2610735 cpu cycles (100 % of 1 thread). MT scaling factor: 7.94
F:\Temp>crcbench
1 thread(s) 2587300 cpu cycles (100 % of 1 thread). MT scaling factor: 1.00
2 thread(s) 2591936 cpu cycles (100 % of 1 thread). MT scaling factor: 2.00
3 thread(s) 2966658 cpu cycles (114 % of 1 thread). MT scaling factor: 2.62
4 thread(s) 3318273 cpu cycles (128 % of 1 thread). MT scaling factor: 3.12
5 thread(s) 3311967 cpu cycles (128 % of 1 thread). MT scaling factor: 3.91
6 thread(s) 2997183 cpu cycles (115 % of 1 thread). MT scaling factor: 5.18
7 thread(s) 2793220 cpu cycles (107 % of 1 thread). MT scaling factor: 6.48
8 thread(s) 2605273 cpu cycles (100 % of 1 thread). MT scaling factor: 7.94
CPU is an Opteron 6128.F:\Temp>crcbench
1 thread(s) 2591451 cpu cycles (100 % of 1 thread). MT scaling factor: 1.00
2 thread(s) 2592157 cpu cycles (100 % of 1 thread). MT scaling factor: 2.00
3 thread(s) 2592291 cpu cycles (100 % of 1 thread). MT scaling factor: 3.00
4 thread(s) 2593343 cpu cycles (100 % of 1 thread). MT scaling factor: 4.00
5 thread(s) 2595047 cpu cycles (100 % of 1 thread). MT scaling factor: 4.99
6 thread(s) 2594137 cpu cycles (100 % of 1 thread). MT scaling factor: 5.99
7 thread(s) 2598689 cpu cycles (100 % of 1 thread). MT scaling factor: 6.98
8 thread(s) 2599617 cpu cycles (100 % of 1 thread). MT scaling factor: 7.97
F:\Temp>crcbench
1 thread(s) 2591609 cpu cycles (100 % of 1 thread). MT scaling factor: 1.00
2 thread(s) 2592904 cpu cycles (100 % of 1 thread). MT scaling factor: 2.00
3 thread(s) 2591829 cpu cycles (100 % of 1 thread). MT scaling factor: 3.00
4 thread(s) 2592925 cpu cycles (100 % of 1 thread). MT scaling factor: 4.00
5 thread(s) 2593471 cpu cycles (100 % of 1 thread). MT scaling factor: 5.00
6 thread(s) 2594952 cpu cycles (100 % of 1 thread). MT scaling factor: 5.99
7 thread(s) 2598849 cpu cycles (100 % of 1 thread). MT scaling factor: 6.98
8 thread(s) 2596708 cpu cycles (100 % of 1 thread). MT scaling factor: 7.98
F:\Temp>