RT is running slow on my new iMac

Software RawTherapee
41

I have the a slightly lower end model of iMac (27in 5K, 3.4Ghz core i5, 16GB ram, Radeon Pro 570) and RT is super slow on it. I just timed it with a stop watch. RT takes 14.45 seconds to open. When I grab the exposure slider and move it to the right it takes a second or more for the slider to catch up to where the mouse pointer has moved.

On my other computer, an old windows 10 machine with an AMD FX 8350, 32GB of ram, and a 1920x1080 monitor, RT is much faster. The sliders move in conjunction with the mouse pointer. The program opens in just a few seconds. It’s like a totally different program.

I’ve tried most of the suggestions in this thread to make it faster on the iMac. Lowering the screen resolution helps a little but RT is still far too slow. This is with both 5.5 and 5.6.

Output quality from RT seems to be at an all time high though. It’s excellent.

42

Have you tried the dev branch build? Also which macos version?

43

It’s been this way in both macOS 10.14.4 and 10.14.5 and with both RT 5.5 and 5.6. The dev branch is not noticeably faster.

I assumed that RT was slow on my old iMac, a 2013 model, because everything was slow on it. But, RT feels about the same on the new machine as it did on the old machine while the other programs I use are significantly faster.

44

The video is not jerky on this side. I think what you are interpreting as a jerky video is the sluggish rawtherapee behavior that I am trying to demonstrate.

45

Please post / link your AboutThisBuild.txt file so we can eliminate common mistakes.

46

AboutThisBuild.txt file:

AboutThisBuild.txt (610 Bytes)

47

Please try with a 5.6 build from here

48

@heckflosse Could there be an issue with -mtune=generic on MacOS ? Or an issue with clang ?

49

I don’t know anything about MacOS, means there could be an issue or not. I just don’t know.

50

Ping @HIRAM

51

I could suggest going down to regular 1080p resolution and see if that helps.

I could try a targeted build for cpu you have. It would only affect the RT code, a the dependencies I have built up should be all generic.

I’m still not having any sluggishness issues on the macs I have access to, which are i3, i5, and E5.

Ps. I think I added -mtune=generic for compatibility with Core2Duo.

52

Hi. Tried the 5.6 build. I can’t notice any any difference.

53

Hi, I tried to reduce the resolution to one step below “standard”. that helped a lot. Thanks. Then I guess the problem is that the machine lacks horsepower.

54

Interesting, thanks for testing. Will have to make a note :memo: It sounds like the 4K+ resolutions make RT annoyingly sluggish on Mac.