The results so far: 1. Bad news: The reqs/sec seem much lower than before. i.e. Does the bug fix have a performance hit?
2. Good news: The "input port closed" error seemed to be gone with 5.3.0.16. Except ... 3. Bad news: I just got it to happen again, with 5.3.0.16: $ /Applications/Racket_v5.3.0.16/bin/racket bug-example.rkt serve: port=8081 hostname=#f timeout=60 peek-bytes-avail!: input port is closed context...: /Applications/Racket_v5.3.0.16/collects/racket/port.rkt:1114:4: try-again This after doing `ab' runs like this: $ ab -n 10000 -c 5 http://localhost:8081/ The thing is, I did about 10 such runs of `ab' -- with the same "server" running the whole time. In other words, the likelihood of the error happening seems to grow the longer the server runs. It _seems_ to happen _later_ with 5.3.0.16 than with 5.2.1. OTOH with this sort of issue I suppose that could be "random". I wonder can anyone else elicit these problems trying to run it, too? As I've done little with `sync' and events in Racket to-date, I'm half-wondering if the issue is me being muddled. So if anyone wants to code-review me, I'd welcome the critique, too. Thanks again. On Fri, Aug 3, 2012 at 8:36 PM, Greg Hendershott <greghendersh...@gmail.com> wrote: > Thank you for such a quick reply! > >> I see that you're using `read-bytes-avail!-evt', which has problems in >> v5.2.1 that are fixed for v5.3. The problems include triggering a bug >> in `sync', which is also fixed for v5.3. > > Well, I only tried read-bytes-avail!-evt after getting similar errors > with regexp-match-evt. So if the fix is specific to rba-evt, that's > probably not it. > > Also although it was maybe buried in the comments, I had the same > errors with 5.2 as 5.2.1. FWIW. > >> Does a nightly build behave any differently? > > I'm trying 5.3.0.16 right now. ApacheBench is not eliciting the errors > ... so far. Previously it could take awhile before the errors would > start to pop up. Fingers crossed ... > > On Fri, Aug 3, 2012 at 7:56 PM, Matthew Flatt <mfl...@cs.utah.edu> wrote: >> I see that you're using `read-bytes-avail!-evt', which has problems in >> v5.2.1 that are fixed for v5.3. The problems include triggering a bug >> in `sync', which is also fixed for v5.3. >> >> Does a nightly build behave any differently? >> >> At Fri, 3 Aug 2012 19:11:44 -0400, Greg Hendershott wrote: >>> Even the distilled code is maybe a wee bit long for here, so I made a gist: >>> https://gist.github.com/3252353 >>> >>> I wanted to try doing non-blocking I/O and a reactor event loop. >>> >>> The gist is an excerpt to simplify the problem case. What I left out >>> is the fun stuff where Racket could make this less painful, such as >>> using continuations or simply generators to avoid >>> nested-callback-chain heck. But before the fun stuff, the foundation: >>> >>> Under a light load everything works fine. But ApacheBench with -c > 2 >>> is making it unhappy, as described in the comments. >>> >>> Sometimes it will blow through 10,000 reqs at -c 20 with no problem. >>> And giving at least 2X better reqs/sec than comparable >>> thread-per-connection example. Yay! >>> >>> But on most runs it's getting errors with "input port closed". And >>> rarely I will get a channel? from sync when it should only be an >>> eof-object? or integer. And rarely I even get a Racket seg fault. >>> Boo! >>> >>> So. Probably I'm doing one or more really stupid things? Any advice >>> would be welcome -- thank you! >>> ____________________ >>> Racket Users list: >>> http://lists.racket-lang.org/users ____________________ Racket Users list: http://lists.racket-lang.org/users
