P: CS6 Slow compared to CS5.1 with large files

I tested that "Ray Stofberg" karate snapshot montage.

Though I could not open it into Photoshop CS5 without confirming a warning that some data was going to be deleted to keep layers editable, Photoshop CS6 was was EXACTLY as responsive in moving layers around as Photoshop CS5. I even timed things with a stopwatch.

And yes, disabling the thumbnails made things faster.

But why is this coming up only now? It's no worse than it was before.

Downloading now...

PSCS6_large_file_test.psb only shows the layer thumbnail slowdown.
It needs about 5 times as many layers to really show the snap slowdown.

Ray Stofberg's file from 5 days ago was a good example - but I'm not sure if it's still on his website. Try http://wtrns.fr/a11OwVlSE27cSI

It sure smells to me like something specific is going wrong on some systems and not others.

I'm not willing to guess whether it could be a GPU or software issue, but I'm just not seeing significant degradation with Photoshop CS6 vs. CS5 on ANY documents.

The only thing I've seen a slight degradation with in Photoshop CS6 is painting performance with very large brushes, and that's 5% to 10%. I sense that Photoshop CS6 is not throwing away mouse events as readily as its predecessor, opting for quality over speedup. Certainly a 10% reduction in brush performance in some cases wouldn't make me complain about it.

Do you have a file (or know of one online) with which you can demonstrate a definite difference?

Just tested with the file given (on PC workstation).

1. Photoshop CS5 took 35 seconds to open the file, Photoshop CS6 took 27.

2. It's not blazingly fast to move layers around in either version, but there's really no obvious difference for me in Photoshop CS5 vs Photoshop CS6. With the image fit to screen (12.5% zoom) I see maybe 4 or 5 updates per second while moving any of the layers around. If anything, Photoshop CS6 may be a hair more responsive. I don't think this is unreasonable performance for moving 64 megapixels around.

3. The screen updated for me in real time in both versions when I move the points on the Curves layer, after perhaps a slight initial delay on the very first movement.

4. Panning at any zoom level is just smooth, and the flick pan settles nicely.

5. Zooming from 12.5% to 100% via the right-click menu resulted in a momentary jump the first time I did it, after some animation had occurred. Subsequent zooms were smooth the whole way.

Honestly, I see no degradation whatsoever - and in fact I see some improvements in Photoshop CS6 vs. CS5 - as viewed on my PC workstation with this test image.

-Noel

The ones I've looked at had 200 to 600 layers to really show a significant slowdown. It's not the size of the document, but the number of layers that have to be invalidated or searched for their bounds that causes the slowdown (plus a VM lock inside the bounds search).

There is no reason to scale back one's methods when CS5 works flawlessly, and the hardware can back you up.

I had a file that was 6000x5000 or so... 200 layers, many smart objects, layer FX, masks etc... worked great in CS5, then in CS6 I lowered the res to 3000x2000, merged many layers.. and still performed much slower than cs5 with all layers intact..

How the heck many layers would I need to see a slowdown? 80+ layers in a 60+ megapixel image that saves as 5 GB on disk seems like fair bit already.

It also seems that for folks working on such large/deep images, an ultramodern, fully equipped computer would be a must. 48 GB or more of RAM would be advisable.

It seems to me that if it takes literally hundreds of layers to cause noticeable problems, why not adjust the workflow a bit so as not to need so many layers? I do understand that not everyone uses Photoshop for the same things, but isn't the goal in keeping everything separate to facilitate future editability. If that's destroyed by the document becoming unweildy to edit, where's the advantage?

The PSCS6_large_file_test.psb.zip from above has just finished downloading. I think I'll have a look...

No, it is not platform specific. But it will get worse with increased layer count.

And may get worse depending on the actual content of the layers (since both known problems have to search for the bounds of the layer repeatedly).