New scheduler

[k-nasa]

This PR is a successor to #631 .

This PR contains only the following parts:

This PR replaces the current scheduler with a new one. Differences:

• The executor and reactor are more closely coupled. We don't have a networking driver thread anymore. Instead, executor threads poll mio.

What we did in this PR

• Removed the mechanism to launch a new thread.
• Revived spawn_blocking

[yoshuawuyts]

@k-nasa overall this looks good; I can't spot any bugs through review. But still, the fact that a few bugs slipped through CI on an earlier round makes me feel a bit nervous about merging it as-is; I didn't write this part of the code, and don't trust myself to do a full review.

What would help here is if we could add more tests -- at least some we know would have failed if we hadn't caught them during review. Having those would provide more confidence that these changes actually work as intended. Thanks!

[dignifiedquire]

I think asking folks to test this branch in larger apps or libraries will also help to find bugs and build confidence

…

On 22. Mar 2020, 12:42 +0100, Yoshua Wuyts ***@***.***>, wrote: @k-nasa overall this looks good; I can't spot any bugs through review. But still, the fact that a few bugs slipped through CI on an earlier round makes me feel a bit nervous about merging it as-is; I didn't write this part of the code, and don't trust myself to do a full review. What would help here is if we could add more tests -- at least some we know would have failed if we hadn't caught them during review. Having those would provide more confidence that these changes actually work as intended. Thanks! — You are receiving this because you are subscribed to this thread. Reply to this email directly, view it on GitHub, or unsubscribe.

[k-nasa]

@yoshuawuyts @dignifiedquire What about publishing in version 1.6.0-alpha?

[dignifiedquire]

@k-nasa yes, that is the current plan. Cutting an alpha prerelease with this and get folks testing.

[dignifiedquire]

This has been merged to master, we will be releasing a 1.6.0-alpha soon, so please start using either in your projects to test this well.