Separate min and max threads count environment variable for puma configuration

[chiraggshah]

Same environment variable RAILS_MAX_THREADS was being used
for setting the minimum and maximum thread count for puma.
This change makes it obvious and easy to decide which
environment variable to change for setting the min or max.

Don't feel like this is a breaking change as the same
default is maintained.

[rails-bot]

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[chiraggshah]

@schneems : Did you get a chance to review this?

[schneems]

This will break existing settings that assume setting RAILS_MAX_THREADS sets both min and max. How about min threads defaults to the same as max threads unless otherwise explicitly set.

[schneems]

Well it won’t exactly break them but it might be surprising.

[chiraggshah]

@schneems : Would changing it to the following make sense so that it maintains backward compatibility and is not surprising?

max_threads_count = ENV.fetch("RAILS_MAX_THREADS") { 5 }
min_threads_count = ENV.fetch("RAILS_MIN_THREADS") { max_threads_count || 5 }
threads min_threads_count, max_threads_count

[schneems]

yes but the last || isn’t required. Since max_threads_count will always have a value.

…

On Fri, Jul 20, 2018 at 9:51 PM Chirag Shah ***@***.***> wrote: @schneems <https://github.com/schneems> : Would changing it to the following make sense so that it maintains backward compatibility and is not surprising? max_threads_count = ENV.fetch("RAILS_MAX_THREADS") { 5 } min_threads_count = ENV.fetch("RAILS_MIN_THREADS") { max_threads_count || 5 } threads min_threads_count, max_threads_count — You are receiving this because you were mentioned. Reply to this email directly, view it on GitHub <#32984 (comment)>, or mute the thread <https://github.com/notifications/unsubscribe-auth/AADpYJ-RvawfVbrfmsKKnbj-dajnsA55ks5uIpclgaJpZM4UNPQi> .

[chiraggshah]

@schneems : I have made the suggested changes.

[schneems]

Tests are failing I restarted them

[chiraggshah]

Thanks. They have passed now.

[schneems]

Thanks for the PR!

[chiraggshah]

Thanks for the review. That was my first PR to Rails. :)