Hi Am 08.01.20 um 03:25 schrieb Rong Chen: > Hi Thomas, > > The previous throughput was reduced from 43955 to 35691, and there is a little increase in next-20200106, > but there is no obvious change after the patchset: OK, I would have hoped for some improvements. Anyway, thanks for testing. Best regards Thomas >   > commit: > f1f8555dfb ("drm/bochs: Use shadow buffer for bochs framebuffer console") > 90f479ae51 ("drm/mgag200: Replace struct mga_fbdev with generic framebuffer emulation") > > f1f8555dfb9a70a2 90f479ae51afa45efab97afdde9 > ---------------- --------------------------- > %stddev %change %stddev > \ | \ > 43955 ± 2% -18.8% 35691 vm-scalability.median > > commit: > > 9eb1b48ca4 ("Add linux-next specific files for 20200106") > 5f20199bac ("drm/fb-helper: Synchronize dirty worker with vblank") > > next-20200106 5f20199bac9b2de71fd2158b90 > ---------------- -------------------------- > %stddev change %stddev > \ | \ > 38550 38744 > 38549 38744 vm-scalability.median > > > Best Regards, > Rong Chen > > On 1/6/20 9:19 PM, Thomas Zimmermann wrote: >> Hi Feng, >> >> do you still have the test setup that produced the performance penalty? >> >> If so, could you give a try to the patchset at [1]? I think I've fixed >> the remaining issues in earlier versions and I'd like to see if it >> actually improves performance. >> >> Best regards >> Thomas >> >> [1] >> https://lists.freedesktop.org/archives/dri-devel/2019-December/247771.html >> >> Am 05.08.19 um 14:52 schrieb Feng Tang: >>> Hi Thomas, >>> >>> On Mon, Aug 05, 2019 at 12:22:11PM +0200, Thomas Zimmermann wrote: >>> >>> [snip] >>> >>>>>> 2019-08-03 19:29:17 ./case-anon-cow-seq-hugetlb >>>>>> 2019-08-03 19:29:17 ./usemem --runtime 300 -n 4 --prealloc --prefault >>>>>> -O -U 815394406 >>>>>> 917318700 bytes / 659419 usecs = 1358497 KB/s >>>>>> 917318700 bytes / 659658 usecs = 1358005 KB/s >>>>>> 917318700 bytes / 659916 usecs = 1357474 KB/s >>>>>> 917318700 bytes / 660168 usecs = 1356956 KB/s >>>>>> >>>>>> Rong, Feng, could you confirm this by disabling the cursor or blinking? >>>>> Glad to know this method restored the drop. Rong is running the case. >>>>> >>>>> While I have another finds, as I noticed your patch changed the bpp from >>>>> 24 to 32, I had a patch to change it back to 24, and run the case in >>>>> the weekend, the -18% regrssion was reduced to about -5%. Could this >>>>> be related? >>>> In the original code, the fbdev console already ran with 32 bpp [1] and >>>> 16 bpp was selected for low-end devices. [2][3] The patch only set the >>>> same values for userspace; nothing changed for the console. >>> I did the experiment becasue I checked the commit >>> >>> 90f479ae51afa4 drm/mgag200: Replace struct mga_fbdev with generic framebuffer emulation >>> >>> in which there is code: >>> >>> diff --git a/drivers/gpu/drm/mgag200/mgag200_main.c b/drivers/gpu/drm/mgag200/mgag200_main.c >>> index b10f726..a977333 100644 >>> --- a/drivers/gpu/drm/mgag200/mgag200_main.c >>> +++ b/drivers/gpu/drm/mgag200/mgag200_main.c >>> @@ -162,7 +162,7 @@ int mgag200_driver_load(struct drm_device *dev, unsigned long flags) >>> if (IS_G200_SE(mdev) && mdev->mc.vram_size < (2048*1024)) >>> dev->mode_config.preferred_depth = 16; >>> else >>> - dev->mode_config.preferred_depth = 24; >>> + dev->mode_config.preferred_depth = 32; >>> dev->mode_config.prefer_shadow = 1; >>> >>> My debug patch was kind of restoring of this part. >>> >>> Thanks, >>> Feng >>> >>>> Best regards >>>> Thomas >>>> >>>> [1] >>>> https://cgit.freedesktop.org/drm/drm-tip/tree/drivers/gpu/drm/mgag200/mgag200_fb.c?id=5d17718997367c435dbe5341a8e270d9b19478d3#n259 >>>> [2] >>>> https://cgit.freedesktop.org/drm/drm-tip/tree/drivers/gpu/drm/mgag200/mgag200_fb.c?id=5d17718997367c435dbe5341a8e270d9b19478d3#n263 >>>> [3] >>>> https://cgit.freedesktop.org/drm/drm-tip/tree/drivers/gpu/drm/mgag200/mgag200_fb.c?id=5d17718997367c435dbe5341a8e270d9b19478d3#n286 >>>> >>>>> commit: >>>>> f1f8555dfb9 drm/bochs: Use shadow buffer for bochs framebuffer console >>>>> 90f479ae51a drm/mgag200: Replace struct mga_fbdev with generic framebuffer emulation >>>>> 01e75fea0d5 mgag200: restore the depth back to 24 >>>>> >>>>> f1f8555dfb9a70a2 90f479ae51afa45efab97afdde9 01e75fea0d5ff39d3e588c20ec5 >>>>> ---------------- --------------------------- --------------------------- >>>>> 43921 ± 2% -18.3% 35884 -4.8% 41826 vm-scalability.median >>>>> 14889337 -17.5% 12291029 -4.1% 14278574 vm-scalability.throughput >>>>> >>>>> commit 01e75fea0d5ff39d3e588c20ec52e7a4e6588a74 >>>>> Author: Feng Tang >>>>> Date: Fri Aug 2 15:09:19 2019 +0800 >>>>> >>>>> mgag200: restore the depth back to 24 >>>>> >>>>> Signed-off-by: Feng Tang >>>>> >>>>> diff --git a/drivers/gpu/drm/mgag200/mgag200_main.c b/drivers/gpu/drm/mgag200/mgag200_main.c >>>>> index a977333..ac8f6c9 100644 >>>>> --- a/drivers/gpu/drm/mgag200/mgag200_main.c >>>>> +++ b/drivers/gpu/drm/mgag200/mgag200_main.c >>>>> @@ -162,7 +162,7 @@ int mgag200_driver_load(struct drm_device *dev, unsigned long flags) >>>>> if (IS_G200_SE(mdev) && mdev->mc.vram_size < (2048*1024)) >>>>> dev->mode_config.preferred_depth = 16; >>>>> else >>>>> - dev->mode_config.preferred_depth = 32; >>>>> + dev->mode_config.preferred_depth = 24;> dev->mode_config.prefer_shadow = 1; >>>>> >>>>> r = mgag200_modeset_init(mdev); >>>>> >>>>> Thanks, >>>>> Feng >>>>> >>>>>> The difference between mgag200's original fbdev support and generic >>>>>> fbdev emulation is generic fbdev's worker task that updates the VRAM >>>>>> buffer from the shadow buffer. mgag200 does this immediately, but relies >>>>>> on drm_can_sleep(), which is deprecated. >>>>>> >>>>>> I think that the worker task interferes with the test case, as the >>>>>> worker has been in fbdev emulation since forever and no performance >>>>>> regressions have been reported so far. >>>>>> >>>>>> >>>>>> So unless there's a report where this problem happens in a real-world >>>>>> use case, I'd like to keep code as it is. And apparently there's always >>>>>> the workaround of disabling the cursor blinking. >>>>>> >>>>>> Best regards >>>>>> Thomas >>>>>> >>>> -- >>>> Thomas Zimmermann >>>> Graphics Driver Developer >>>> SUSE Linux GmbH, Maxfeldstrasse 5, 90409 Nuernberg, Germany >>>> GF: Felix Imendörffer, Mary Higgins, Sri Rasiah >>>> HRB 21284 (AG Nürnberg) >>>> >>> >>> _______________________________________________ >>> dri-devel mailing list >>> dri-devel@lists.freedesktop.org >>> https://lists.freedesktop.org/mailman/listinfo/dri-devel >>> > -- Thomas Zimmermann Graphics Driver Developer SUSE Software Solutions Germany GmbH Maxfeldstr. 5, 90409 Nürnberg, Germany (HRB 36809, AG Nürnberg) Geschäftsführer: Felix Imendörffer