Displaying a struct containing gpuArray fields takes an extremely long time in R2024b

I find that when I create a struct (or object) whose fields are large gpuArrays, it takes an extremely long time (1-2 minutes) to display the struct at the command line. Example:

>> c.data=gpuArray.rand(266,354,894,'single');

>> tic; c, toc

c =

struct with fields:

data: [266×354×894 gpuArray]

Elapsed time is 100.266106 seconds.

I have observed this in R2024b on two platforms,

(1) Windows 10; NVIDIA GeForce RTX 4080 SUPER

(2) Windows 11; NVIDIA RTX 5000 Ada Generation

Does anyone know why this might be happening?

[Matt J]

Also, it doesn't seem to happen in R2024a, so I'm guessing R2024b introduced this problem.

Answer 1

[Edric Ellis]

Thanks for reporting this, I can reproduce the problem here (though not so severely). For now I'm afraid the only workaround is "don't do that".

[Matt J]

Thanks @Edric Ellis. Do you think it's a problem that would eventually be solved with a patch download, rather than upgrading to a new Matlab version?

Answer 2

[Matt J]

Here's a possible workaround:

c.a=1; c.b=2; c.data=gpuArray.rand(100,100,100,'double');

tic; c, toc

c =

struct with fields:

a: 1

b: 2

data: [100×100×100 gpuArray]

Elapsed time is 0.170750 seconds.

tic; shellClass.gather(c), toc

ans =

struct with fields:

a: 1

b: 2

data: [100×100×100 gpu_double]

Elapsed time is 0.000875 seconds.