On Wed, Dec 20, 2023 at 2:40 PM Joe Orton <jor...@redhat.com> wrote: > > I was surprised this made a difference to the behaviour on the wire. It > seems like the chunk filter has suboptimal behaviour here. If you take > an output brigade like either: > > a) [HEAP FLUSH EOS] > b) [HEAP FLUSH EOS FLUSH] > > in both cases the chunk filter would output two brigades: > > [chunk-hdr HEAP crlf FLUSH] [last-chunk EOS] > > Significantly there is no FLUSH in the second brigade even for case (b), > because the chunk filter also drops everything after EOS. It would be > clearly better/correct if the chunk filter produces a single brigade for > this very common output pattern: > > [chunk-hdr HEAP crlf last-chunk FLUSH EOS] > > correctly preserving the semantics of the FLUSH. I've tried this here: > > https://github.com/apache/httpd/pull/400
Thanks, looks good to me. > > > > On Mon, Oct 9, 2023 at 2:50 PM Eric Norris <enor...@etsy.com> wrote: > > > > > > At Etsy, we use mod_php and were investigating what we thought was > > > surprising behavior - that code executed during PHP's shutdown phase > > > prevented the request from terminating, even if we didn't expect to send > > > any additional output to the client. > > > > > > We determined that this was not surprising given mod_php's > > > implementation, but after we developed a proof-of-concept patch that > > > sent an EOS bucket and a flush bucket via a "userland" PHP function, we > > > were surprised that it didn't work when compression was enabled for the > > > request. I'm wondering if these cases are valid/supported though: c) [HEAP EOS FLUSH] d) [HEAP EOS] [FLUSH] (with separate FLUSH but on r->output_filters still) which seems to be what mod_php and the "userland" POC do? I thought nothing should be sent on r->output_filters after EOS (only c->output_filters might forward metadata in between requests), and at least in ap_http_chunk_filter() this won't work since, as Joe said, everything after EOS being dropped breaks c) and the filter not removing itself after EOS breaks d). So I think what the POC or mod_php should be doing is [FLUSH EOS] or something might not work in the chain sooner or later? Regards; Yann.
