[BUG] performance regression

[kojq]

[ALPM] upgraded fastfetch (2.12.0-1 -> 2.13.0-1) [ALPM] upgraded fastfetch (2.13.0-1 -> 2.13.1-1)

Introduced either 2.13.0 or 2.13.1, fastfetch can be significantly slower outputting from the GPU line and onward, so I suspect some recent commit regarding GPU (Linux) (on NVIDIA). It occurs on git as well (https://github.com/fastfetch-cli/fastfetch/commit/59c853fb0172d12a0fe286625fa2bdbbdf7d1e14).

[kojq]

introduced by https://github.com/fastfetch-cli/fastfetch/commit/e9b535d2776ffed04b069283e6846744ba6a8b8d with detectPci(options, gpus, &buffer, &drmDir, entry->d_name);

[kojq]

I see. The issue is with pPciPath++.

[CarterLi]

can be significantly slower

I can't reproduce it on my laptop with RTX 3070 Ti. e9b535d2776ffed04b069283e6846744ba6a8b8d should not make much difference of performance. The major difference introduced in 2.13.0 is https://github.com/fastfetch-cli/fastfetch/blob/dev/src/detection/gpu/gpu_linux.c#L40-L52 which tries to call the DRM driver of nvidia GPU. It is only used to grab a driver name and version but should not affect performance too.

You may try --gpu-detection-method pci, which effectively avoids calling the DRM driver. Please paste the result of hyperfine 'fastfetch -s gpu -l none' 'fastfetch -s gpu -l none --gpu-detection-method pci'

[kojq]

I don't think hyperfine output would be useful as you have to wait a couple of seconds and not use fastfetch in immediate succession for this to occur. The flag to avoid calling the DRM driver does resolve the issue though.

[kojq]

I am using nouveau rather than the proprietary drivers.

[CarterLi]

How much time does it cost? --stat should print time usage for individual modules.

[CarterLi]

What does fastfetch -s gpu --format json --stat print?

[kojq]

1-2 seconds. I'm currently on mobile with no computer, so can't give output now. Will do later.

[CarterLi]

Really? Is nouveau that slow?

[CarterLi]

Anyway, if you can confirm where the problem is, I can cut a hotfix release today.

[kojq]

I can try to get back to you with the output within an hour from now. Otherwise, will be tomorrow.

[kojq]

--stat

 `+sso+:-`                 `.-/+oso:     Terminal: foot 1.17.2                                                                                                                                                                            2ms
`++:.                           `-/+/    Terminal Font: monospace (8pt)                                                                                                                                                                   0ms
.`                                 `/    CPU: AMD Ryzen 9 5900HS (16) @ 4.68 GHz                                                                                                                                                          1ms
                                         GPU 1: NVIDIA GeForce RTX 3060 Mobile / Max-Q [Discrete]
                                         GPU 2: AMD Radeon Vega Series / Radeon Vega Mobile Series @ 0.40 GHz [Integrated]                                                                                                             1546ms
                                         Memory: 1.85 GiB / 15.03 GiB (12%)                                                                                                                                                               0ms

-s gpu --format json --stat

[
  {
    "type": "GPU",
    "result": [
      {
        "coreCount": null,
        "memory": {
          "dedicated": {
            "total": null,
            "used": null
          },
          "shared": {
            "total": null,
            "used": null
          }
        },
        "driver": "nouveau 1.4.0",
        "name": "GeForce RTX 3060 Mobile / Max-Q",
        "temperature": null,
        "type": "Discrete",
        "vendor": "NVIDIA",
        "platformApi": "DRM (card1)",
        "frequency": null
      },
      {
        "coreCount": null,
        "memory": {
          "dedicated": {
            "total": null,
            "used": null
          },
          "shared": {
            "total": null,
            "used": null
          }
        },
        "driver": "amdgpu 3.57.0",
        "name": "Radeon Vega Series / Radeon Vega Mobile Series",
        "temperature": null,
        "type": "Integrated",
        "vendor": "AMD",
        "platformApi": "DRM (card2)",
        "frequency": 0.4
      }
    ],
    "stat": 1544
  }
]

[CarterLi]

Does this patch fix your issue?

diff --git a/src/detection/gpu/gpu_linux.c b/src/detection/gpu/gpu_linux.c
index 9387ce4e..5f6e93dd 100644
--- a/src/detection/gpu/gpu_linux.c
+++ b/src/detection/gpu/gpu_linux.c
@@ -70,7 +70,7 @@ static const char* drmDetectDriver(FFGPUResult* gpu, FFstrbuf* pciDir, FFstrbuf*
 static bool pciDetectDriver(FFGPUResult* gpu, FFstrbuf* pciDir, FFstrbuf* buffer, FF_MAYBE_UNUSED const char* drmKey)
 {
     #if FF_HAVE_DRM_H
-    if (drmKey)
+    if (drmKey && !ffStrEquals(drmKey, "card1"))
     {
         drmDetectDriver(gpu, pciDir, buffer, drmKey);
         if (gpu->driver.length > 0) return true;

[kojq]

yep. the patch resolves it.

[CarterLi]

This suggests that nouveau driver is bad

[kojq]

You could do a workaround or simply a wontfix.

[kojq]

FYI, prior to turing cards using nouveau will probably be the ones affected, as our cards can use NVK with mesa 24.1+ (which I suspect would have better performance). Anyway, gtg. Ciao.

[CarterLi]

You could do a workaround

The only workaround is that we dont try to call DRM drivers for nouveau.

However we dont know if it is nouveau if we dont ask the driver.

[CarterLi]

which I suspect would have better performance

We only ask for driver name and version but nothing else. I didnt know it is that hard to tell who and how old the nouveau driver is.