rack-timeout | Abort requests | Frontend Framework library

I'm trying to upgrade my Ruby on Rails application to Ruby 3.0.1. I'm getting an error when the server is starting on Render.com. I'm also getting the same error when running specs on my local machine

SOLUTION: I was running ruby 2.6.6p146 with Bundler version 2.2.4. As per @thiebo's suggestion, I downgraded to Bundler 2.1.2 and it worked! Steps:

1. $ gem uninstall bundler
2. [then delete Gemfile.lock]
3. $ gem install bundler --version '2.1.2'

I've tried these options, but nothing has worked: heroku push error: "Could not detect rake tasks"

I can indeed run bundle exec rake -P against my app

I tried rescuing the Rakefile, and putting rspec into production in my Gemfile: Heroku could not detect rake tasks (LoadError: cannot load such file -- rspec/core/rake_task)

I added 'rake' to the gemfile.

Tried adding gem 'rack-timeout': Heroku 'Could not detect rake tasks'

I also followed this thread to no avail: https://github.com/rubygems/bundler/issues/3640

Here's the error:

I'm trying to deploy my Rails 5.0 on heroku after a bundle update. I'm blocked by an issue on assets:precompile

In our Rails application we are using rack-timeout 0.4.2 and have it configured in config/initializers/timeout.rb for prod and staging like so:

I want to remove ActionCable from my Rails app, and I found this which says to replace gem rails in the Gemfile with all of rails component gems minus gem 'action_cable'. I did this and I manually removed action cable from gemfile.lock

This is on Heroku, but as of now I don't think it is related to that specifically. We also use rack-timeout gem which should be killing processes after 30 seconds. Please see below why it looks like that is not happening in some cases.

We have a very huge pool of puma workers/threads, 5 workers and 20 threads per worker. At the time of this issue as mentioned, we had 5 heroku dynos running, so this would have been 500 total puma instances available for working requests. With this many, I find it very hard to believe that a few long running requests caused such a high number of 503s.

I set up puma metrics and added them to a custom logging thread, and here is an example of a snapshot where we had an uptick in 503s from this AM, where the puma backlog results are bizarre:

I'm trying to push a forked repo to Heroku but Heroku won't accept the push because Ruby 2.3.1 wasn't accepted. I changed the version to 2.3.3 in the Gemfile and running bundle install --without production, but oddly enough it was still considered to be 2.3.1. The same things happened even after trying other Ruby versions, such as 2.4.0.

Reference:

What I thought was an issue with a rack-timeout setting is actually an issue with ActiveRecord::Base.transaction

When a request hits one of our update endpoints and that update is handled in a transaction

for even something as simple as

We're seeing occasional timeouts in our application that appear to trace to Redis, though I'm not entirely sure. We have a module that we include in some of our jobs to reduce duplication of heavier work: