latency issues

[astraw]

Hi, first, many thanks for tokio-serial. It has been very useful to us.

I raise the following issue to ensure you are aware of it.

In the course of debugging realtime performance of an application (which will be open sourced in the coming few months, but isn't there yet) we observed some timing issues with overall scheduling of async tasks by the tokio runtime. Specifically, in a linux program involving simultaneous serial connections to different devices and other tokio tasks such as a webserver and a tokio::time::Interval timer with 1 msec resolution, the ticks from the timer would be very irregular. In the process of debugging, we wrote kioto-serial and found that using it instead of tokio-serial solved this latency issue. Since that point, we have not delved deeper into tokio-serial to attempt to localize the issue.

For us, this is no longer a particularly pressing issue because switching from tokio-serial to kioto-serial has now solved the problem for us.

(Potentially related: #52).