Woes about 6 Core CPU Lr/Ps Performance (PC Upgrade)

[Anonymous Beard]

Hello all, i will start my listing my current setup:

PC

CPU A10 7870k APU (1140 single thread CPUZ score)

8GB 2400Mhz RAM

SSD for OS/Programs

HDD for storage & catalogue etc

CAMERA

Panasonic G7

RAW files are 19MB

As of right now, I am on average importing + generating 1:1 previews 100-150 RAW files and sorting through them etc (yes that isn't many but I am a beginner and aim to up my workload as I improve)

I usually end up exporting a third of that.

My more intense work consists of 70% Lr+Ps as well as a bunch of Chrome tabs. The other 30% being video editing (Hitfilm 4 Express)

I'm in the process of deciding on which parts I want for a new, editing focused, PC on somewhat of a budget. My current thoughts are as follows:

A) i5 7600k (2390 single thread CPUZ score @ 4.7GHz)  with a Z270 board and 16GB 3000Mhz RAM - my initial thought was this combo

B) Ryzen 5 1600 (2163 single thread CPUZ score @ 3.7GHz)  with a 3.7GHz OC with a B350 board and 16GB 3200Mhz RAM - however, seeing the single core benchmarks of this CPU, it's only 10% less than the i5 (would I really notice the extra 10%?) but with the advantage of the extra cores and threads for the SAME PRICE.

My dilema now is I've just read posts on here saying Lr doesn't do well with 6+ core CPUs which makes me very confused as what I should do for overall improved performance over my current APU.

I'm aware Lr and Ps are mostly single threaded programs but the video work utilizes multiple cores and threads, so with all of the above in mind and the fact both builds cost near enough the same money, what are your thoughts?

I really hope someone can help me.

Thanks

MB

[johnrellis]

I'm aware Lr and Ps are mostly single threaded programs

LR uses multiple threads in many parts of the application, including importing, generating previews, Develop, and exporting.

Unless you have the opportunity to benchmark a motherboard with LR before buying, the conservative course is to limit yourself to four fast cores and high-performance memory.  While some users have reported that limiting LR to use only four cores on systems with more than four cores is a viable workaround, others have reported that workaround doesn't help them.

[bob frost]

LR CC2015.10 uses all 6/12 cores of my i7-5930K cpu quite happily while importing, exporting, or rendering previews. Using just 4/8 cores increases cpu usage per core, but no overall increase in speed.  My only complaint is the slowdown over a period of time; I haven't found a solution for that yet.

Disabling Intel SpeedStep seems to have made LR more snappier in things like scrolling through the Library, and the latest version of Win10 seems to have speeded things up a touch as well.

Bob Frost

[Anonymous Beard]

My only complaint is the slowdown over a period of time; I haven't found a solution for that yet.

How long are you in Lr before you start noticing the slowdowns? Also, does exiting Lr and then immediately opening it again fix the slowdown before it then starts slowing down again?

MB

[Anonymous Beard]

While some users have reported that limiting LR to use only four cores on systems with more than four cores is a viable workaround, others have reported that workaround doesn't help them.

Is the process of limiting your CPU simple and straightforward and, more importantly, is it safe for the CPU? If limiting Lr to 4/8, would the rest of my PC (i.e. doing other tasks as well as Lr) have access to all 6/12 or just 2/4?

MB

[johnrellis]

Is the process of limiting your CPU simple and straightforward and, more importantly, is it safe for the CPU? If limiting Lr to 4/8, would the rest of my PC (i.e. doing other tasks as well as Lr) have access to all 6/12 or just 2/4?

See here for the recipe: Lightroom: Slow performance on Xeon CPUs | Photoshop Family Customer Community .  But as you can read in the rest of that thread, it helps some people but not others.  It's perfectly safe, and it just limits LR to using 4 processors -- Windows and other apps all use the full set of processors. 

But if you can't benchmark this ahead of time, I think the conservative course is to restrict your purchase to a CPU with 4 cores.  Otherwise, you run the significant risk that your machine will perform horribly.

[Anonymous Beard]

Hmm, a real dilemma indeed. How like is Adobe to fix this problem? I could always get the 1500X 4 core 8 thread which has near identical performance as the 7600k 4 core 4 thread but for £40 less, but I'd really feel like I was just settling rather than getting something better.

That said:

A10 - 7870K 4/4 Stock Clocked @ 3.9GHz Scores single/multi 1140 / 5504

1500X - 4/8 OC'd @ 3.7GHz = £190

7600K - 4/4 OC'd @ 4.7GHz = £230

1600 - 6/12 OC'd @3.7GHz = £220

Single/Multi Thread Scores

1500X 4/8 - 2163 / 9727

7600k 4/4 - 2390 / 9301

1600 6/12 - 2163 / 14574

Overall it's a a very close race between my 3 choices BUT any one of them SHOULD give a nice performance boost (hopefully) over my APU.

[Anonymous Beard]

I apologies for all these replies I keep sending you but I have another middle ground solution I'd like your opinion on.

I just remembered that the AM4 (Ryzen) socket platform will be supported for at least the next 4/5 years so that opens up the option of getting the 4 core 8 thread 1500X now and getting the performance increases over my current APU while we wait and pray Adobe fixes the higher core count slowdown problems in Lr. If they do fix the problem, I could then get whatever 6 core 12 thread CPU is good at the time.

Just to clarify, 4 core 8 thread CPUs dont have the slowdown issues found on 6 core and higher?

Many thanks for your input on this subject.

[johnrellis]

Just to clarify, 4 core 8 thread CPUs dont have the slowdown issues found on 6 core and higher?

There's no pattern of persistent performance problems with 4 core/8 thread processors, as there is with 6+ cores. I'd guess that most users running LR on machines purchased in the last couple of years are on 4/8 processors.