Unreal Engine Compiling Shaders on Asus Zephyrus S17 Terrible Slow

[nyankocool]

Honestly I love my Asus Zephyrus GX701LXS. Intel i7-108075H CPU 2.30Ghz 32 GB ram.

The machine has been doing great on everything. Except…

Unreal Engine shader compilation which doesn’t utilize the CPU fully and takes forever.

The shader compilation is really slow, not just ordinary slow but around 1/5 the speed of my desktop machine which is also 8 core machine. This is insane.

Same issue when compiling Unreal Engine source code with this machine. It never fully utilized the CPU and took insane amount of time.

Doing shader complication on a similar desktop machine I always get full utilization and it takes way less time.

I have checked and there is no thermal throttling at all so it cannot be the issue.

Could the memory be the problem somehow? The memory is configured currently with 2 16GB DDR4-3200 modules in Dual Channel configuration. HWInfo says they are Samsung SO-DIMMs.

I am not even sure if the memory can be upgraded, but if I was to, say upgrade this to 64GB, would that make the shader compliation to fully utilize the CPU? I tend to see faster results with 64 GB systems overall. Asus does not support me starting to pull machine like this apart but I have a feeling that maybe 64 GB would be doable.

I need this to work or I will be forced to buy a new laptop. Would rather see more use of this one as new ones are insane expensive.

[jamiej]

For source compilation UBT expects 1.5GB / core, you’ll need at least 12GB free memory on 8 core system. That should be achievable on 32GB system.

In your build logs search for:

Determining max actions to execute in parallel (8 physical cores, 16 logical cores)
Executing up to 8 processes, one per physical core

The line following the above may state memory limitation, and limiting number of parallel build actions.

Regarding shader compiler, it absolutely uses CPU and more cores the better or having a distributed build system like incredibuild or other system. There are a number of configuration parameters in Engine/Config/BaseEngine.ini under the section [DevOptions.Shaders], but honestly you’re not going to get a lot of gains there on that machine. Sorry.