> Am 28.05.2024 um 15:45 schrieb Yann Ylavic <ylavic....@gmail.com>:
>
> On Tue, May 28, 2024 at 12:47 PM Stefan Eissing via dev
> <dev@httpd.apache.org> wrote:
>>
>>> Am 27.05.2024 um 14:08 schrieb Yann Ylavic <ylavic....@gmail.com>:
>>>
>>> Per our discussion the other day, if you want to avoid c1 connections
>>> to be killed by mpm_event on high load in this case, I think you can
>>> do this here:
>>>
>>> Index: modules/http2/h2_c1.c
>>> ===================================================================
>>> --- modules/http2/h2_c1.c (revision 1918003)
>>> +++ modules/http2/h2_c1.c (working copy)
>>> @@ -147,6 +147,7 @@ apr_status_t h2_c1_run(conn_rec *c)
>>> && mpm_state != AP_MPMQ_STOPPING);
>>>
>>> if (c->cs) {
>>> + c->clogging_input_filters = 0;
>>> switch (conn_ctx->session->state) {
>>> case H2_SESSION_ST_INIT:
>>> case H2_SESSION_ST_IDLE:
>>> @@ -159,6 +160,7 @@ apr_status_t h2_c1_run(conn_rec *c)
>>> * See PR 63534.
>>> */
>>> c->cs->sense = CONN_SENSE_WANT_READ;
>>> + c->clogging_input_filters = 1;
>>> 03465}
>>> break;
>>> case H2_SESSION_ST_CLEANUP:
>>> --
>>>
>>> c->clogging_input_filters = 1 will tell the MPM to always call
>>> process_connection() hooks after the WRITE_COMPLETION state did the
>>> poll(), rather than entering the (killable) keepalive state.
>>>
>>> Looks like the correct workaround with current mpm_event..
>>
>> Just so I get this right. It will return to processing after the
>> write is done or after a POLLIN happened? In the first case, it
>> will not have really a positive effect on worker allocations,
>> seems to me.
>
> Yes, it will return to processing after POLLIN happens thanks to
> CONN_SENSE_WANT_READ, even if there are pending output data.
> But it's a really convoluted handling of POLLIN/POLLOUT in mpm_event,
> with the need of that obscure c->clogging_input_filters..
> So I just created https://github.com/apache/httpd/pull/448 to do that
> better (and it includes the changes to h2_c1_run() too).
> The plan could be to merge that to trunk and include it in your
> backport proposal (if it works for you)?
>
Great!
>
> Regards;
> Yann.
