> On Nov. 4, 2015, 11:25 a.m., Neil Conway wrote:
> > Can we test that more thoroughly than just "make check"? e.g., if there's a 
> > unit test that tries to enter this logic with multiple threads at once, 
> > running that with gtest_repeat=1000 would be nice.

There are tons of methods in libprocess that call `process::initialize` as a 
side-effect, but at the same time, the libprocess test suite starts out with an 
essentially race-free init call (See: 
https://github.com/apache/mesos/blob/master/3rdparty/libprocess/src/tests/main.cpp#L52).
  So any `--gtest_repeat` or `--gtest_shuffle` won't actually test the init 
code.  (The master and agent also call init once on startup.)

I'm not sure how valuable it will be to, say, to spawn a bunch of threads that 
call `process::initialize`.  Do you have any suggestions?


> On Nov. 4, 2015, 11:25 a.m., Neil Conway wrote:
> > 3rdparty/libprocess/src/process.cpp, line 742
> > <https://reviews.apache.org/r/39949/diff/1/?file=1115784#file1115784line742>
> >
> >     I wonder if it would be an improvement to rename these variables to 
> > reflect what they are used for more clearly.
> >     
> >     For example: maybe call them "initialize_started" and 
> > "initialize_complete" (and change the second so that it goes from false -> 
> > true instead of true -> false).

That sounds very reasonable.  I'll rename (and see if anyone objects :).


- Joseph


-----------------------------------------------------------
This is an automatically generated e-mail. To reply, visit:
https://reviews.apache.org/r/39949/#review105115
-----------------------------------------------------------


On Nov. 4, 2015, 10:58 a.m., Joseph Wu wrote:
> 
> -----------------------------------------------------------
> This is an automatically generated e-mail. To reply, visit:
> https://reviews.apache.org/r/39949/
> -----------------------------------------------------------
> 
> (Updated Nov. 4, 2015, 10:58 a.m.)
> 
> 
> Review request for mesos, Benjamin Hindman and Joris Van Remoortere.
> 
> 
> Repository: mesos
> 
> 
> Description
> -------
> 
> The initialization synchronization logic contains three conditions, which 
> check:
> 1) Was `initialize` called and is it done?
> 2) Was `initialize` called and is it not done?
> 3) Are you the first to call `initialize`?
> 
> Condition (3) uses `compare_exchange_strong` between `initialized` and 
> `false`.  This returns `true` (and sets `initialized` to true) iff the caller 
> is the first to reach that expression.
> 
> The second simultaneous caller of `initialize` will either satisify condition 
> (2) or (3) and then wait on `initializing`.  For the second caller, (2) and 
> (3) are identical because `compare_exchange_strong` between `true` and 
> `false` will always return false, thereby putting the second caller into the 
> waiting loop.
> 
> 
> Diffs
> -----
> 
>   3rdparty/libprocess/src/process.cpp 
> a94712b9ac3b60fb047b3a5a4d84a56fa4d02313 
> 
> Diff: https://reviews.apache.org/r/39949/diff/
> 
> 
> Testing
> -------
> 
> `make check`
> 
> 
> Thanks,
> 
> Joseph Wu
> 
>

Reply via email to