Tate, Hongliang Tian

@StanPlatinum Could you give some feedback for this PR?

> Measuring test time is also useful to prevent performance regression, as there are tests that contains iterations. Tests are usually built with debug mode. The resulting execution time cannot...

> The measurement is really primitive and is inaccurate if tasks can be preempted. Preemption is not really a concern. The reported time is intended to give the user a...

I think it is time to revisit the design decision of making `ktest` relatively independent from the aster-frame. Code like this ```rust /// A set of functions needed to perform...

@StevenJiang1110 Could you review this PR?

@liqinggd Could you take a look at this PR? Your inputs are highly appreciated.

Read-ahead is an important I/O optimization technique. Good job on bring it to Asterinas! My concern is about the downside of read-ahead. It has been shown that the read-ahead mechanism...

I think the change proposed in this PR is correct. As a further optimization, `switch_to_task` should do nothing if the given `next_task` is equal to the `current_task`. In this case,...

> I have a question: under what circumstances next_task might be equivalent to current_task? When there is only one single runnable task. This situation is common for microbenchmarks. > Additionally,...

@lrh2000 #821 has a commit that shares mostly the same optimization idea as this PR. But I think this PR executes a slightly better. So let's discuss it here. The...