Prevent rayon from causing OOM-Sigkill

[mwurps]

Hi all,

I was trying out rayon to speed up a computation:

let result = seeds.par_iter().map(|x| seed_to_location(&maps, *x)).min();

I want to transform all elements of a pretty large vector (seeds) with a function (seeds_to_location) and find the minimum of the transformed values. I thought this would be a good use case to try out rayon. However, I found that this computation consumes all of my RAM, until it gets inevitably shot down with a SIGKILL signal.

Is there a way to avoid this from happening with rayon or to lower it's memory consumption?

Thanks :)

[cuviper]

Rayon doesn't allocate much memory itself. Does seed_to_location use much memory? What is the peak memory usage if you run that as a sequential .iter()? Or with fewer threads like env RAYON_NUM_THREADS=2?