Here's the current status... The API isn't cast in stone yet. I'm only guessing that mod_perl cares about this issue based on wild assumptions I'm making about the crash I posted at http://mail-archives.apache.org/mod_mbox/perl-dev/201311.mbox/%3CCAKUrXK6C3R_F3NdA%2BJUGYOqppvnoQJLTGQ9%2BA916vuMb0g9dig%40mail.gmail.com%3E
If mod_perl doesn't have any sort of connections/request thread affinity (i.e., is unaffected when a request or connection starts being handled on a different native thread), that would be great to know too, since that simplifies the discussion. ---------- Forwarded message ---------- From: Jeff Trawick <traw...@gmail.com> Date: Tue, Nov 26, 2013 at 3:17 PM Subject: Re: Does mod_perl/mod_??? need a hook called when a request/conn leaves the original worker thread? To: Apache HTTP Server Development List <d...@httpd.apache.org> On Tue, Nov 26, 2013 at 9:01 AM, Jeff Trawick <traw...@gmail.com> wrote: > On Tue, Nov 26, 2013 at 8:55 AM, Graham Leggett <minf...@sharp.fm> wrote: > >> On 26 Nov 2013, at 3:51 PM, Jeff Trawick <traw...@gmail.com> wrote: >> >> > As it turns out (or, why didn't I refresh my understanding before), the >> MPM only knows about the conn_rec. >> > >> > * It could do extra work to learn about the request in order to pass >> the request to the new hook. >> > * It could avoid that extra work for configurations that don't have a >> module that implements the hook. >> > >> > I'm leaning towards not having the MPM bother with any of that. Such >> magic is well within the scope of a module that cares about detaching from >> the thread anyway. >> >> It would be nice if there was a clean and consistent way for >> c->output_filters to become r->output_filters, and when the request is >> cleaned up for the c->output_filters to be reverted back to what it was >> before. >> >> This way content and resource filters could take advantage of write >> completion in future. >> > > Interesting... I don't know exactly what "clean ... way" will mean in > this context, but I can look at early-request-hook+request-pool-cleanup > processing to let the MPM track the current r for a connection. > > >> >> Regards, >> Graham >> -- >> >> > > Here's a first draft for suspend/resume hooks: http://people.apache.org/~trawick/suspend_resume_hooks_r1.txt This maintains r inside the event MPM connection state. >From a module that tries to log r->the_request when the connection is suspended or resumed: [pid 31968:139866574595840] suspend, r 7f3530002970 GET /ubuntu-12.04.3-desktop-i386.iso HTTP/1.1 [pid 31968:139866566203136] resume, r 7f3530002970 GET /ubuntu-12.04.3-desktop-i386.iso HTTP/1.1 [pid 31968:139866566203136] suspend, r 7f3530002970 GET /ubuntu-12.04.3-desktop-i386.iso HTTP/1.1 [pid 31968:139866557810432] resume, r 7f3530002970 GET /ubuntu-12.04.3-desktop-i386.iso HTTP/1.1 [pid 31968:139866557810432] suspend, r 7f3530002970 GET /ubuntu-12.04.3-desktop-i386.iso HTTP/1.1 [pid 31968:139866549417728] resume, r 7f3530002970 GET /ubuntu-12.04.3-desktop-i386.iso HTTP/1.1 ... [pid 31968:139866725664512] suspend, r 0 (For detecting the end of the request or connection, the module needs to use a cleanup on the appropriate pool as always.) Todos (that I know of so far :) ): 1. call the new hooks from places other than process_socket() 2. consider passing a coarse, non-MPM-specific, representation of the state on the hook calls -- Born in Roswell... married an alien... http://emptyhammock.com/ -- Born in Roswell... married an alien... http://emptyhammock.com/
