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GPU AP tuning: new set of test tasks for GPU AP

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Raistmer:
Here first results of unroll param tuning for HD6950. CPU idle, Cat 12.1, OS Vista x86.

As one can see there is some saturation in performance when unroll factor reached certain threshold. Too low unrolls considerably inefficient. Take into account that real world task will have signals in it _ some % of blanking. Each factor adds slowdown when unroll increases (memory requirement increases with unroll too) so I would reccommend to stay at minimal effective unrolls and not rise them too much w/o need.

Raistmer:
And the same run for C-60 APU. CPU idle, Cat 11.12 mobile, OS Win7 x64
Quite different picture. Bench run was aborted due to system shutdown (I leaved netbook on soft surface and it overheated). Will repeat with good cooling to see if such performance decrease at higer unroll is overheating effect (APU freq drop maybe? ) or it's inherent to device.

Raistmer:
Want to share picture TThrottle provided.
Stages:
1. Netbook idle with screen off
2. Screen goes online
3. Benchmark started, many ap_genwiz tasks are done
4. First test Clean_01LC.wu task running.

Raistmer:
And another picture:

1: Screen was switched off during task run
2: External air cooling applied
3: screen goes off during task run then waked up.

Looks like there is performance drop when screen goes off. Not only temperature decreases, but execution time increases too.

It can explain such erratic times I get on netbook and monotonic dependence on discrete GPU where screen always ON. To check this I will do run with display always ON and then with display turned off after 1 min of keyboard idle.

Fredericx51:
Is it usefull to do test with I7-2600 + 2x HD5870 GPUs, using AP rev.1316 app. with unroll 15;
ffa_block  10240 ffa_block_fetch 5120?  These give the lowest runtime and CPU time.
{Cat 12.4;  AMD-APP (SDK) 2.4; OpenCL 1.2}

Or try this on GTX470 or 480?

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