Configurable thread pool size

[gsquire]

Fixes #27

I'm not sure if this is desired so if it isn't, feel free to close it.

[ashleygwilliams]

hey @gsquire ! thanks so much for this. this makes the default value way more intelligent. it turns out that the original spirit of my extremely not detailed issue ( #27 ) was that we would also accept an env variable that would designate the number.

if you are interested in adding that to this PR we would love it! otherwise we'll accept this and do the env variable work in another PR. just lemme know! thanks for the contribution!

[ashleygwilliams]

this looks good, but there's another small feature we may wait on if the @gsquire is interested, so holding off merging til they respond :)

[gsquire]

I can certainly add that. Here is how I envision the flow:

If the environment variable is present (let me know what name sounds good), try and parse it as a u32. If this fails or the variable isn't present, then I will default to the number of CPUs. How does that sound?

[ashleygwilliams]

hey @gsquire ! that sounds absolutely perfect. thank you so much!!

[ashleygwilliams]

i am not picky about the name, maybe NUM_POOLS or just POOLS, open to whatever you think is best :)

[ashleygwilliams]

cc i dont know if @steveklabnik has a pref

[gsquire]

I can update that soon and then change it if need be based on his response :)

[steveklabnik]

Rust's testing framework uses RUST_TEST_THREADS to set the number of threads, what about SIMPLESERVER_THREADS?

Env vars don't have namespacing, so you kind of have to do it in the name...

[gsquire]

Ok I adjusted it to SIMPLESERVER_THREADS. Let me know if you would like me to squash my commits.

[ashleygwilliams]

this looks great @gsquire ! if you wanna fix up that last commit into the main commit you've got i think we can ship this! thank u so much for your patience, flexibility, and work ✨ ❤️

[gsquire]

No problem, happy to contribute. Should be all set now.