Re: [Gimp-user] Debugging Perf on Linux

[Elle Stone <ellestone ninedegreesbelow com>]

On 03/27/2018 09:11 PM, Robert Bieber wrote:
> I assume this has to be a bug, since I'm running the same software and 
> getting the exact opposite of the results I'd expect running it on 
> different machines, but what can I do to diagnose it and get some data 
> that might help resolve it?  The error console isn't showing anything, 
> here's what I get in my terminal when opening an image and running 
> wavelet decompose, if that helps at all: https://pastebin.com/TCEgYqPr
>
> Seeing color management stuff in the console did make me think to try 
> turning color management off, which did make basic image operations run 
> faster, but wavelet decompose is still running intolerably slow.  And of 
> course retouching with color management disabled isn't an ideal 
> long-term solution.  Any ideas?

I looked at the pastebin file, nothing looked out of the ordinary - I 
see similar terminal output. But maybe someone else will spot something.

Earlier today I was doing some soft proofing, switching profiles back 
and forth. At one point I clicked the wrong field in Preferences without 
noticing, so accidently selected the printer profile as the monitor 
profile instead of the soft proofing profile.

GIMP slows down to a crawl when using a LUT monitor profile (even if 
it's really a monitor profile instead of an accidentally selected 
printer profile).

So is there any chance that your monitor profile at home is a LUT 
profile? What about the image's assigned profile - was it possibly a LUT 
profile? And/or was soft proofing somehow activated?

Also, try operating at 32f instead of 16i, which will eliminate some 
internal precision changes. And try disabling opencl and setting the 
number of threads to "1".

Best,
Elle