Testing ReBAR Behavior

[aolszowka]

I wanted to open up a discussion to spin off the conversation that is happening here: #11 (comment) between @hitman72ita and @MrAnonymous7122

@xCuri0 does a good job of this little section of the FAQ that mentions using tooling such as GPU-Z https://github.com/xCuri0/ReBarUEFI/wiki/Flashing-modified-UEFI#verifying-resizable-bar-is-enabled and mentions "Or just run a game/benchmark to see the real world improvement you get."

For users who aren't super tech savvy maybe it would be worth explicitly pointing to some standard test suite?

[xCuri0]

I think 3DMark Time Spy shows an improvement atleast for me, but remember the less CPU bottleneck you have the less gain rebar will give.

[aolszowka]

I was digging more and ran across this tool: https://github.com/GpuZelenograd/memtest_vulkan

I think this might do what I want. If I'm understanding correctly with a larger ReBAR I should see slightly better performance. My testing seems to show that.

As you'll see the gains were modest, but for my purposes ReBAR support is more to get the Intel Drivers working smoothly.

Am I interpreting this correctly?

Specifications

• Motherboard: ASRock Z77 Extreme4 - Modifications Start from Latest 3.00 Beta * BIOS Available From ASRock
• GPU: ASRock Intel Arc A380 Challenger ITX 6GB OC
• BAR Size: 8192MB (8GB ReBarState 13)
• RAM: 32GB

ReBarState 0

Tester console logging started at 2024-03-28T15:14:11.028317Z

1: Bus=0x00:00 DevId=0x56A5   6GB Intel(R) Arc(TM) A380 Graphics
Tester worker logging started at 2024-03-28T15:14:11.503839Z
Standard 5-minute test of 1: Bus=0x00:00 DevId=0x56A5   6GB Intel(R) Arc(TM) A380 Graphics
      1 iteration. Passed  0.1869 seconds  written:    1.9GB  54.9GB/sec        checked:    3.8GB  24.5GB/sec
      7 iteration. Passed  1.1520 seconds  written:   11.2GB  53.3GB/sec        checked:   22.5GB  23.9GB/sec
     35 iteration. Passed  5.1389 seconds  written:   52.5GB  55.8GB/sec        checked:  105.0GB  25.0GB/sec
    198 iteration. Passed 30.0692 seconds  written:  305.6GB  55.5GB/sec        checked:  611.2GB  24.9GB/sec
    362 iteration. Passed 30.1423 seconds  written:  307.5GB  55.8GB/sec        checked:  615.0GB  25.0GB/sec
    526 iteration. Passed 30.0880 seconds  written:  307.5GB  55.9GB/sec        checked:  615.0GB  25.0GB/sec
    690 iteration. Passed 30.0875 seconds  written:  307.5GB  55.9GB/sec        checked:  615.0GB  25.0GB/sec
    854 iteration. Passed 30.0851 seconds  written:  307.5GB  55.9GB/sec        checked:  615.0GB  25.0GB/sec
   1018 iteration. Passed 30.0854 seconds  written:  307.5GB  55.9GB/sec        checked:  615.0GB  25.0GB/sec
   1182 iteration. Passed 30.1155 seconds  written:  307.5GB  55.9GB/sec        checked:  615.0GB  25.0GB/sec
   1346 iteration. Passed 30.1379 seconds  written:  307.5GB  55.7GB/sec        checked:  615.0GB  25.0GB/sec
   1510 iteration. Passed 30.0882 seconds  written:  307.5GB  55.9GB/sec        checked:  615.0GB  25.0GB/sec
Standard 5-minute test PASSed! Just press Ctrl+C unless you plan long test run.
Extended endless test started; testing more than 2 hours is usually unneeded
use Ctrl+C to stop it when you decide it's enough

ReBarState 13

Tester console logging started at 2024-03-28T15:22:10.990100Z

1: Bus=0x00:00 DevId=0x56A5   6GB Intel(R) Arc(TM) A380 Graphics
Tester worker logging started at 2024-03-28T15:22:12.201571Z
Standard 5-minute test of 1: Bus=0x00:00 DevId=0x56A5   6GB Intel(R) Arc(TM) A380 Graphics
      1 iteration. Passed  0.2146 seconds  written:    1.9GB  46.0GB/sec        checked:    3.8GB  21.6GB/sec
      7 iteration. Passed  1.1814 seconds  written:   11.2GB  52.1GB/sec        checked:   22.5GB  23.3GB/sec
     33 iteration. Passed  5.0760 seconds  written:   48.8GB  50.8GB/sec        checked:   97.5GB  23.7GB/sec
    192 iteration. Passed 30.0916 seconds  written:  298.1GB  51.9GB/sec        checked:  596.2GB  24.5GB/sec
    357 iteration. Passed 30.0096 seconds  written:  309.4GB  56.2GB/sec        checked:  618.8GB  25.2GB/sec
    521 iteration. Passed 30.0242 seconds  written:  307.5GB  55.8GB/sec        checked:  615.0GB  25.1GB/sec
    685 iteration. Passed 30.1300 seconds  written:  307.5GB  53.3GB/sec        checked:  615.0GB  25.2GB/sec
    851 iteration. Passed 30.1686 seconds  written:  311.2GB  56.3GB/sec        checked:  622.5GB  25.3GB/sec
   1017 iteration. Passed 30.1605 seconds  written:  311.2GB  56.3GB/sec        checked:  622.5GB  25.3GB/sec
   1183 iteration. Passed 30.1609 seconds  written:  311.2GB  56.3GB/sec        checked:  622.5GB  25.3GB/sec
   1348 iteration. Passed 30.0055 seconds  written:  309.4GB  56.2GB/sec        checked:  618.8GB  25.2GB/sec
   1514 iteration. Passed 30.1641 seconds  written:  311.2GB  56.3GB/sec        checked:  622.5GB  25.3GB/sec
Standard 5-minute test PASSed! Just press Ctrl+C unless you plan long test run.
Extended endless test started; testing more than 2 hours is usually unneeded
use Ctrl+C to stop it when you decide it's enough

[xCuri0]

I don't think Arc cards function properly without resizable BAR so yes you'll see a huge improvement on them

[hitman72ita]

I changed my dying Sapphire RX580 4Gb Nitro+ (2gb rebar working) with a used XFX RX5600XT THICC III Ultra 14 gps (8gb rebar working). Stock 24.10.1 driver. lame an old i7 6700K stock clock

SUPERPOSITION bench 1080p Extreme

RX5600XT, rebar OFF
3940
FPS: Min 24.10, Avg 29.47, Max 34.71

RX5600XT, rebar ON
4020
FPS: Min 24.64, Avg 30.07, Max 35.44

at the end the same result