@Pascal_Obry ehm maybe it’s a stupid question but is the 2.7 package available here sufficiently up to date to include the modifcations to lighttable that you were discussing?:
https://software.opensuse.org/download.html?project=graphics:darktable:master&package=darktable
(reason being that it’s already compiled obviously)
The OBS repo should be very up-to-date, as it builds from got master.
@aadm: yes, those packages should have the lighttable speed-up. but as usual with dev packages, backup your darktable data and also not that you won’t be able to downgrade (or you’ll have to restore your backup).
Ok well in the end I cloned the git repository, installed the extra stuff I needed to compile darktable and the process was quick and painless. So I now have the latest build, see the screenshot below reporting the latest commit of yesterday:
And what I’ve found from a first test is that indeed zipping around the lighttable is much faster than before, but then the the lag between using keyboard shortcuts to set stars and color labels feels the same as before. I have then tried to clicking the star icons on the bottom of each thumbnail and that is instantaneuous, no lag at all (not sure if that was also the case before as I normally use keyboard shortcuts to do this). On the other hand, clicking on the color label in the bottom of the screen:
…that is also slow (~1sec from clicking to actually seeing the color label appearing on the thumbnail.
So there it is. For now I’ll sneak my way around using the mouse and only stars to do my editing (meaning selecting photos), but I think it could be helpful to make the editing process quicker by allowing the user to move around the lighttable and setting stars and labels and keywords (tags) with keyboard shortcuts and these actions should have a nearly-instantaneous feedback on screen.
I hope you can find these findings useful and reproduceable. Having gone through the binary building process I could help in testing new releases if you want.
Two other things I’ve noticed:
For:
For the slowness, this is because when a star or color-label is added we redraw everything as if the lighttable is using a corresponding filter we need to refresh it completely. I suppose that we can do that only if the corresponding filter is activated, for filename order there is no need for the whole redraw. I’ll try to improve that next…
Your second point is fixed in master.
Applying rating and colorlabels from keyboard should be faster now. If you can test again that would be nice.
Noticeable speedup in the current master when using tags and colors/star ratings 
Ok so just tried the latest version, the bug we discussed (point 2 above) is fixed, great! About how fast are stars and labels applied from keyboard I’m sorry but I’m not seeing any difference from before… But @matejmarti did notice a speedup!
PS: sorry again for being such a newbie but I have installed lua, compiled 5.3 directly from source and then installed so I now have the bin and the libraries all on my system (under /usr/local but that’s in the path), however when compiling darktable I do get this message like it’s not finding lua:
-- Checking for one of the modules 'lua53;lua5.3;lua-5.3;lua'
-- Lua support: System library for lua 5.3 not found (to use darktable's version use -DDONT_USE_INTERNAL_LUA=Off)
I’ve used the buttons in the gui to apply the color labels during my short test last night. I will check again today using the keyboard shortcuts.
@aadm: for Lua sorry I’m no expert, you may try to remove your build directory and restart from scratch.
You know I’ve checked how’s the situation by using only the gui and as before, stars are ok, they are applied instantaneously, but color labels are not. I wonder what’s the difference with your setup. Do you have a more powerful computer? Is your library perhaps smaller (mine is close 50k images now and they are all contained in only a few directories; again I don’t think this should be an issue but you never know).
Anyway, the problem remains when using keyboard shortcuts for both stars and color labels.
I will also say that the same lag occurs when applying tags.
Yes, my library is quite a bit smaller, only 12k images. But i’m also usaully only working on about 100 images or so. Selecting some images with the collect module and applying color labels and tags, both via keyboard and gui, seems a bit faster to me with the recent changes to master.
Latest update: guys I have just got the latest package from git (this time I didn’t compile it myself but realized that I could just get the latest one from https://software.opensuse.org/download.html?project=graphics:darktable:master&package=darktable) and, wow the speedups are there! No more lag in setting color labels and stars from keyboard shortcuts! Excellent work @Pascal_Obry, this is making my editing so much faster now, it will smooth out the editing I’m doing for a personal project/book!
PS: for the record, this is the version I’m using:
darktable_2.7.0_git251.fff6ec3c5_amd64.deb
@aadm: that’s good to hear! we finally have something for people with 4k monitors or above. that’s also nice to have more reactivity on an HD monitor BTW (that’s what I used). Thanks all for testing. If you find issues the best is to report them on our GitHub.
Yes. As I wrote at the beginning I’ve experienced this slowness with a fairly large (I think) library (~50k images) both using the internal laptop display (HD) and the external monitor (2560x1440 px). I hope this scales up also to 4K display but have no way of testing it.
On another note, the latest compile did introduce a small bug which I’ve described here (I hope it’s ok my description, first time filing a github “issue”): https://github.com/darktable-org/darktable/issues/2007
Maybe this introduced another bug: Redraw failure in lighttabe · Issue #2009 · darktable-org/darktable · GitHub.
Should be fixed now.
Hello,
I hope that I am not necro bumping, but I still notice a certain amount of lag in lighttable. I am running the git version : 2.7.0+2119~g2e7b77290 on Arch Linux, which I assume is more recent than darktable_2.7.0_git251.fff6ec3c5_amd64.deb.
The lag occurs especially when rating. Either with the mouse or keyboard. Setting color labels seem instantaneous.
I find that I also have a similar amount of lag when selecting an image or a group of images in lighttable.
The lag is about 1 second. A bit annoying in a workflow when needing to process many images.
I have a fairly recent computer, with an i7-8650U.
Is there anything I can provide to troubleshoot this ?
Since we are so close to release, git master is updating daily.
You can start darktable from the terminal with darktable -d all and see if anything registers in the terminal output, or you can attach gdb to the DT process.