Mac Pro CPU Upgrade from 6 Cores to 12 Cores Really Help?

[zhp3nn]

Hi Lightroom Team,

I'm Planning to upgrade my Mac Pro 2013 CPU from 6 cores 3.5Ghz to 12 cores 2.7Ghz

as I can see in the Light room FAQ :

• 64-bit, multiple-core processor (for best performance, up to six cores; the extra power is especially important if you use multiple or high-resolution monitors, which require more power)

It looks like Lightroom can use only 6 core maximum?

is that means

If I use 12 cores 2.7Ghz CPU may be slower than 6 Cores 3.5Ghz CPU?

May due to the clock speed of the 12Cores CPU is slower than 6 Cores?

The main thing I really care is editing speed in Develop Mode,  not File Export Speed.

In this case will 12 cores slower than 6 Cores?

Thanks a lot.

[dj_paige]

I'm afraid there is no way to know this other than to try it. I have seen some people report that now (as opposed to an earlier point of time) Lightroom does use all the cores in your computer.

I believe that any CPU from a 2013 computer will be slower than a new CPU.

I also believe that there are many complaints about new Mac computers being horribly slow in the develop module, and in my opinion, this comes from the fact that most (all?) of these new Mac computers have 4K or 5K screens, with a middle-of-the-road CPU and possibly an above average GPU. This is not a good combination (4K or 5K screen and middle-of-the-road CPU) for Lightroom. But maybe you don't have (or are not planning to have) a 4K or 5K screen. Brushing and spot healing are known to slow down the develop module if done in large quantities on a photo.

But anyway, if it speeds up the develop module, it will also speed up exporting.

[zhp3nn]

Just hoping the LR Development team can give an idea cores matters or clock speed matters, or can LR use all 12 cores.

[dj_paige]

The Lightroom Development team does not answer questions in this forum, which is primarily a user-to-user forum.

[zhp3nn]

oh... thanks a lot for the info, is there any way can ask the dev team?

[dj_paige]

I don't think so.

[zhp3nn]

updated:

Just upgraded the CPU from 6 to 12 cores

It really improves the export speed a lot

same images take 31mins in 6 cores , takes only 19mins in 12cores.

but in develop   mode it does not fell much difference

[johnrellis]

Just upgraded the CPU from 6 to 12 cores. It really improves the export speed a lot. Same images take 31 mins in 6 cores , takes only 19 mins in 12 cores. But in develop mode it does not fell much difference.

Thanks for sharing your experience -- this will help others.

It's not surprising that you see good speedup with Export but no speedup in Develop. Exporting is inherently and easily parallelizable at a coarse-grained level -- each processor can be working on a separate photo (export is constrained by the relatively large amount of processor time needed to render the exported images).  But Develop is much harder to parallelize, since much of the rendering of an individual pixel depends on computations on other pixels. LR increasingly relies on the graphics processor (GPU) for speeding up Develop rendering.