[erlang-questions] Dirty NIF - classifying as CPU or I/O bound

Steve Vinoski vinoski@REDACTED
Sun Oct 14 17:09:02 CEST 2018

On Sun, Oct 14, 2018 at 10:47 AM Jesper Louis Andersen <
jesper.louis.andersen@REDACTED> wrote:

> On Sun, Oct 14, 2018 at 2:42 PM Roger Lipscombe <roger@REDACTED>
> wrote:
>> If I *don't know* whether the job is going to be CPU bound or I/O bound
>> (it executes arbitrary code provided by a third party), am I safest to just
>> classify the dirty job as CPU-bound? Or is this warning hinting at a
>> disaster of biblical proportions[1] if I even *think* about fudging the
>> classification?
> Either classification risks being wrong, so you can't really do any of
> them safely. The two classifications exist because IO resources and CPU
> resources tend to orthogonally consumed: If we have many IO bound jobs, we
> can still run CPU bound jobs and vice versa. But if you don't know what
> kind of job you are looking at a priori, you have no way to classify it
> correctly.
> You *could* run it with some kind of sandbox environment and then make a
> guess: If it were IO bound last time, it probably still is. But this is
> more involved.

I agree with Jesper, and I'll add that to the best of my knowledge no
disaster of biblical proportions will happen if you guess incorrectly.

-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://erlang.org/pipermail/erlang-questions/attachments/20181014/71936bcb/attachment.htm>

More information about the erlang-questions mailing list