(Delayed) Laggy Viewport, and slow Grease Pencil undo (Resolved on restart, then gets worse again) #86342

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William B · 2021-03-06T17:50:24+01:00

William B commented

2021-03-06 17:50:24 +01:00

System Information
Operating system: Windows-10-10.0.19041-SP0 64 Bits
Graphics card: Intel(R) Iris(R) Plus Graphics 640 Intel 4.5.0 - Build 27.20.100.8854

Blender Version
Broken: version: 2.93.0 Alpha, branch: master, commit date: 2021-03-05 06:10, hash: b5d154f400
Worked: version 2.92 (a build from mid January)

Short description of error
After using Blender for a few minutes, the viewport gets very laggy. Just trying to move a small cube, results in a delay of ~1 second for the object to catch up to the mouse if I quickly try to move it from one side of the viewport to the other. This seems to happen when I have both 3D objects and Grease pencil strokes. Possibly also connected, undoing grease pencil is very slow.

Exact steps for others to reproduce the error
Lag 02.blend

Lag 01.blend
Both of these files were started from scratch with the 2D animation preset. I drew a little, made some shapes, Alt-D duplicated them. Everything worked perfectly, the viewport responded quickly, and undo worked with no noticeable delay. Then I continued to draw and duplicate, and at some point, everything grew sluggish (And continued that way). Moving an object resulted in a long lag, and undoing a grease pencil stroke resulted in a long lag. If I save the file, then re-open it, the lag continues. But if I close out Blender completely, then when I restart, the file behaves normally again. So it is something that is "building up" to eventually cause the lag, but closing blender clears it out and when it starts everything is fine again. This was not an issue with the mid-January build of 2.92 I had been using before installing the release 2.92 or the current 2.93 build.

I haven't been able to duplicate this on a faster computer with a graphics card, but it is very noticeable on this computer. Again, everything works perfectly once Blender is closed and re-opened, but then several minutes into working, the lag returns and becomes very difficult, causing me to have to restart the program many times in a session to continue working.

Thanks! Sorry I don't know exactly what is causing it.

**System Information** Operating system: Windows-10-10.0.19041-SP0 64 Bits Graphics card: Intel(R) Iris(R) Plus Graphics 640 Intel 4.5.0 - Build 27.20.100.8854 **Blender Version** Broken: version: 2.93.0 Alpha, branch: master, commit date: 2021-03-05 06:10, hash: `b5d154f400` Worked: version 2.92 (a build from mid January) **Short description of error** After using Blender for a few minutes, the viewport gets very laggy. Just trying to move a small cube, results in a delay of ~1 second for the object to catch up to the mouse if I quickly try to move it from one side of the viewport to the other. This seems to happen when I have both 3D objects and Grease pencil strokes. Possibly also connected, undoing grease pencil is very slow. **Exact steps for others to reproduce the error** [Lag 02.blend](https://archive.blender.org/developer/F9873538/Lag_02.blend) [Lag 01.blend](https://archive.blender.org/developer/F9873537/Lag_01.blend) Both of these files were started from scratch with the 2D animation preset. I drew a little, made some shapes, Alt-D duplicated them. Everything worked perfectly, the viewport responded quickly, and undo worked with no noticeable delay. Then I continued to draw and duplicate, and at some point, everything grew sluggish (And continued that way). Moving an object resulted in a long lag, and undoing a grease pencil stroke resulted in a long lag. If I save the file, then re-open it, the lag continues. But if I close out Blender completely, then when I restart, the file behaves normally again. So it is something that is "building up" to eventually cause the lag, but closing blender clears it out and when it starts everything is fine again. This was not an issue with the mid-January build of 2.92 I had been using before installing the release 2.92 or the current 2.93 build. I haven't been able to duplicate this on a faster computer with a graphics card, but it is very noticeable on this computer. Again, everything works perfectly once Blender is closed and re-opened, but then several minutes into working, the lag returns and becomes very difficult, causing me to have to restart the program many times in a session to continue working. Thanks! Sorry I don't know exactly what is causing it.

William B commented

2021-03-06 17:50:25 +01:00

Added subscriber: @AquilaTheEagle

Germano Cavalcante commented

2021-03-09 15:24:03 +01:00

Added subscriber: @mano-wii

Germano Cavalcante commented

2021-03-09 15:24:03 +01:00

Changed status from 'Needs Triage' to: 'Needs User Info'

Germano Cavalcante commented

2021-03-09 15:24:03 +01:00

Can you check the System Console (Window -> Toggle System Console) to see if any error messages appear during lag?

Can you check the System Console (`Window -> Toggle System Console`) to see if any error messages appear during lag?

William B commented

2021-03-09 19:06:52 +01:00

I recorded a video, let me know if you want me to upload it somewhere.

During the lag, there were no console messages, but I did notice this message on Quit:
"Error: Not freed memory blocks: 8, total unfreed memory 0.000816 MB"

I recorded a video, let me know if you want me to upload it somewhere. During the lag, there were no console messages, but I did notice this message on Quit: "Error: Not freed memory blocks: 8, total unfreed memory 0.000816 MB"

Germano Cavalcante commented

2021-03-11 14:01:52 +01:00

Changed status from 'Needs User Info' to: 'Needs Triage'

William B commented

2021-04-11 23:50:02 +02:00

I have a hunch that this is caused by the built-in Add On "Add Images as Planes", or having too many image data blocks in the file.

Germano Cavalcante commented

2021-04-14 17:43:37 +02:00

It looks like a duplicate of #87147 (Blender increases ram usage until its too laggy to use after a few minutes of use. ), but I'm also not sure how to replicate the problem.

William B commented

2021-04-15 14:57:11 +02:00

I agree, it is the same issue and can be merged as such. It has something to do with 2D animation (but mine don't actually have animations). I think my comment on Apr11 is probably wrong. I noticed recently that just a simple file with a few strokes works perfectly right when I start Blender, but then after walking away and coming back ~1 hour later, it suddenly was extremely slow. Something seems to happen over time that bogs down blender in these 2D modes. I will see if I can reproduce it on second computer with a graphics card to see if that is related . .

Audrey Schultz commented

2021-04-19 06:37:12 +02:00

Added subscriber: @ImaRealBoi

Richard Antalik commented

2021-09-29 13:52:10 +02:00

Added subscriber: @iss

Richard Antalik commented

2021-09-29 13:52:10 +02:00

Changed status from 'Needs Triage' to: 'Needs User Info'

Richard Antalik commented

2021-09-29 13:52:10 +02:00

I suspect this could be caused by GPU drivers, same issue as #89097, possibly #87147 too.

There is way to check if this is the case by using software opengl emulation:
From https://github.com/pal1000/mesa-dist-win/releases/tag/21.1.1 download file mesa3d-21.1.1-release-msvc.7z.
Then extract files opengl32.dll and libglapi.dll to folder where blender.exe is located.

These libraries will make Blender much slower so you probably don't want to use them long term.

Does using software opengl emulation help (as in memory usage doesn't increase over time as much)?
To double check if .dll files are used correctly, please click on Help > Save System Info and upload file here.

I suspect this could be caused by GPU drivers, same issue as #89097, possibly #87147 too. There is way to check if this is the case by using software opengl emulation: From https://github.com/pal1000/mesa-dist-win/releases/tag/21.1.1 download file mesa3d-21.1.1-release-msvc.7z. Then extract files opengl32.dll and libglapi.dll to folder where blender.exe is located. These libraries will make Blender much slower so you probably don't want to use them long term. Does using software opengl emulation help (as in memory usage doesn't increase over time as much)? To double check if .dll files are used correctly, please click on Help > Save System Info and upload file here.

Richard Antalik commented

2021-10-14 23:20:34 +02:00

Changed status from 'Needs User Info' to: 'Archived'

Richard Antalik closed this issue

2021-10-14 23:20:34 +02:00

Richard Antalik commented

2021-10-14 23:20:34 +02:00

No activity for more than a week. As per the tracker policy we assume the issue is gone and can be closed.

Thanks again for the report. If the problem persists please open a new report with the required information.

No activity for more than a week. As per the tracker policy we assume the issue is gone and can be closed. Thanks again for the report. If the problem persists please open a new report with the required information.

William B commented

2021-10-15 16:08:47 +02:00

This had already been merged I thought with the other thread (https:*developer.blender.org/T87147) so I think it is fine to close it but others having this issue can post on this thread > https:*developer.blender.org/T87147

Richard Antalik commented

2021-10-15 21:54:03 +02:00

Ah sorry I realized that we talked in other thread. I think your issue is different though, so best if you provide info here, and I can reopen this report. Just BTW, in #89097 sign of driver mem leak was that memory usage increased when you resized Blender window, so if this is good thing to check.

William B commented

2021-10-16 16:09:40 +02:00

Ok, I recorded a video now so you can see the issues. This is 3.0 alpha from last week with the same computer >

Operating system: Windows-10-10.0.19041-SP0 64 Bits
Graphics card: Intel(R) Iris(R) Plus Graphics 640 Intel 4.5.0 - Build 27.20.100.8854

I disabled almost everything on startup so nothing else but Blender would have the stage. I recorded the video on my cell phone so it didn't impact computer performance. Mid-video I also reset to factory settings and turn off all the undo.

You can see a few issues >

Blender startup is very slow, takes 30 seconds (also related?)
Resize does immediately impact memory, I had always used full-screen so never noticed that before
Grease-Pencil drawing simple strokes does impact memory (but still plenty to spare) even with undo turned off
FPS and responsiveness starts high (25 FPS), and starts to lag after a few minutes, you can probably tell that the position of the pointer and the drawing starts to get out of sync a few minutes in, then when I start testing the FPS, it drops quite low
In this experiment I don't let it sit for a long time, but I have let it sit overnight and it never improves (not just the system having to "catch up")
Closing the Blend file and starting a new one doesn't help
Impact is less noticeable in the normal 3D view (but there is still delay when trying to move the default cube)
After restarting Blender, (after the init delay), things are back to normal, but quickly progress to laggy state again
Blender oddly crashed towards the end . . I think when I had turned off UnDo and tried to hit Ctrl-Z which caused it to crash. Hadn't noticed it before . . may have been a fluke

It appears that the graphics driver is the issue (when I tested it as mentioned in a previous thread with Mesa, I didn't see the memory increase). But a lot of people will be trying out Blender with computers with similar drivers and they will think it is because of Blender and decide it isn't worth using. We all know it is (worth using), but these errors make it really difficult.

VID_20211016_Blender Lag.mp4

Ok, I recorded a video now so you can see the issues. This is 3.0 alpha from last week with the same computer > Operating system: Windows-10-10.0.19041-SP0 64 Bits Graphics card: Intel(R) Iris(R) Plus Graphics 640 Intel 4.5.0 - Build 27.20.100.8854 I disabled almost everything on startup so nothing else but Blender would have the stage. I recorded the video on my cell phone so it didn't impact computer performance. Mid-video I also reset to factory settings and turn off all the undo. You can see a few issues > - Blender startup is very slow, takes 30 seconds (also related?) - Resize does immediately impact memory, I had always used full-screen so never noticed that before - Grease-Pencil drawing simple strokes does impact memory (but still plenty to spare) even with undo turned off - FPS and responsiveness starts high (25 FPS), and starts to lag after a few minutes, you can probably tell that the position of the pointer and the drawing starts to get out of sync a few minutes in, then when I start testing the FPS, it drops quite low - In this experiment I don't let it sit for a long time, but I have let it sit overnight and it never improves (not just the system having to "catch up") - Closing the Blend file and starting a new one doesn't help - Impact is less noticeable in the normal 3D view (but there is still delay when trying to move the default cube) - After restarting Blender, (after the init delay), things are back to normal, but quickly progress to laggy state again - Blender oddly crashed towards the end . . I think when I had turned off UnDo and tried to hit Ctrl-Z which caused it to crash. Hadn't noticed it before . . may have been a fluke It appears that the graphics driver is the issue (when I tested it as mentioned in a previous thread with Mesa, I didn't see the memory increase). But a lot of people will be trying out Blender with computers with similar drivers and they will think it is because of Blender and decide it isn't worth using. We all know it is (worth using), but these errors make it really difficult. [VID_20211016_Blender Lag.mp4](https://archive.blender.org/developer/F11173905/VID_20211016_Blender_Lag.mp4)

Richard Antalik commented

2021-10-26 04:42:13 +02:00

Changed status from 'Archived' to: 'Needs Triage'

Richard Antalik reopened this issue

2021-10-26 04:42:13 +02:00

Richard Antalik commented

2021-10-26 04:42:13 +02:00

Ok so it seems that there is still this memory leak issue, but it doesn't look like it is causing lag in this case. So I will reopen ticket, but I am out of ideas what could be causing this. It may be unrelated problem with this specific GPU/driver though.