Geir, All, I have examined class library code. It seems that the solution we invented (return EINTR, then loop) was always in place. :-)
Few comments on understanding: 1. EINTR (=4) is renamed to HYPORT_ERROR_SOCKET_INTERRUPTED (=-9). 2. The loop is coded by means of "goto select". 3. The same pattern is dupdupduplicated several times. I have not examined all places, though there could be paths which do not fit the pattern. Honestly, I have examined the only path: pollSelectRead() -> hysock_select_read() -> hysock_select() Summary: We can keep this issue open or close it as won't fix. Meanwhile we should look for the real problem. With best regards, Alexei Fedotov, Intel Java & XML Engineering >-----Original Message----- >From: Geir Magnusson Jr. [mailto:[EMAIL PROTECTED] >Sent: Thursday, October 26, 2006 6:21 PM >To: harmony-dev@incubator.apache.org >Subject: Re: [classlib][luni] signalis interruptus in hysock > > > >Fedotov, Alexei A wrote: >> Geir, >> >> Do I understand correctly that you suggest the following? >> >> 1. hysock_select as its name says should mimic a behavior of select, i. >> e. return the error code from select without changing it. It's ok to >> print a rare debug message. > >Yes, that's what I had the other do (and no, I see no reason to print a >debug message, as upper layers can print if they find an EINTR) > >> >> 2. The correct place for the loop is the module where hysock_select is >> called, or, let me be precise, class lib guys are to fix our networking >> code. > >My plan is to fix it as fixed the other one. It turns out that there >are several layers between java and the OS... > >geir > >> >> >> With best regards, >> Alexei Fedotov, >> Intel Java & XML Engineering >> >>> -----Original Message----- >>> From: Geir Magnusson Jr. [mailto:[EMAIL PROTECTED] >>> Sent: Wednesday, October 25, 2006 10:01 AM >>> To: harmony-dev@incubator.apache.org >>> Subject: Re: [classlib][luni] signalis interruptus in hysock >>> >>> >>> >>> Weldon Washburn wrote: >>>> It seems JIRA is down for maintenance. If HARMONY-1904 is still open >>>> perhaps it makes sense to put a counter in the while (...) { >> select...} >>>> loop. And after every N loops, print a warning/diagnostic message. >>> For whom and to what end? Why not just return EINTR (in hysock speak)? >>> >>>> The >>>> value for N would have to be tuned. I don't know what the best >> number >>>> would >>>> be. Given that 1904 patch is not the final solution, at least a >>> diagnostic >>>> that hints at where the system hangs would be useful. It might make >>> sense >>>> to even print a stack trace. Also, I agree with Ivan below. >> Signals >>> bugs >>>> are very hard to debug. And diagnostics can help us all understand >> the >>>> corner cases better. >>> But so far, no one has shown that the system hangs, or can hang, simply >>> because we return EINTR.... >>> >>> geir >>> >>>> On 10/20/06, Ivan Volosyuk <[EMAIL PROTECTED]> wrote: >>>>> On 10/20/06, Geir Magnusson Jr. <[EMAIL PROTECTED]> wrote: >>>>>> >>>>>> Ivan Volosyuk wrote: >>>>>>> Well, I think that the solution is what Geir suggests. One think >>>>> which >>>>>>> bothers me is following. EINTR can happen in different places >> and >>> the >>>>>>> situations can be quite rare in some circumstances. It can lead >> to >>>>>>> hard to reproduce stability bugs (race conditions). >>>>>> Can you give an example? >>>>> Half a year ago, I was working on the problem. Socket operations get >>>>> sometimes interrupted. We have found out that it occurs sometime >> after >>>>> GC. It was not quite easy as the application was quite big and >>>>> situation - quite rare. >>>>> >>>>> Given the fact, that current implementation of monitor reservation >>>>> code can stop other thread in quite random fashion we should have >> rock >>>>> solid support of EINTR handling everywhere the select(), poll() >> calls >>>>> is used. >>>>> >>>>> -- >>>>> Ivan >>>>> Intel Enterprise Solutions Software Division >>>>> >>>>>>> We should find a >>>>>>> way how to test the implementation. >>>>>> +1! >>>>>> >>>>>> :) >>>>>> >>>>>> geir >>>>> >> --------------------------------------------------------------------- >>>>> Terms of use : http://incubator.apache.org/harmony/mailing.html >>>>> To unsubscribe, e-mail: [EMAIL PROTECTED] >>>>> For additional commands, e-mail: >> [EMAIL PROTECTED] >>>>> >>>> >>
