Re: Unbounded memory usage in mod_dav + mod_headers/mod_deflate/...

[Evgeny Kotkov]

Christophe JAILLET  writes:

> Hi,
>
> while looking at some memory consumption issue in mod_dav, you can also
> have a look at the proposed patches in :
> https://bz.apache.org/bugzilla/show_bug.cgi?id=48130
>
> Definitively not the same approach, but the same goal.

Thanks for the link.  We had a lengthy discussion about the mod_dav's
memory usage during PROPFIND requests in svn-dev@ [1].

However, the problem I described in this thread is different, and it just
happens to have the same visible consequence.

What is probably more important, the dav_send_one_response() function
that has the flaw (see the proposed patch) *just* got promoted into a public
API, and will become the part of the next 2.4.x release [2].  So I prepared
the patch, assuming that it would be better to fix this before it becomes
public.

[1] 
https://mail-archives.apache.org/mod_mbox/subversion-dev/201512.mbox/%3ccap_gpnha4hbfdoc7z1d-k9h_nhm8d7wjyfsf4ouoteuepkj...@mail.gmail.com%3E
[2] https://svn.apache.org/r1756561


Regards,
Evgeny Kotkov

Re: httpd track in Seville

[Luca Toscano]

2016-08-30 15:34 GMT+02:00 Rich Bowen :

> As you know, the CFP for ApacheCon closes in less than 2 weeks. It would
> be awesome if we could pull together an httpd track, highlighting that
> httpd is still the flagship of the ASF, and is still exciting, relevant,
> and alive. The last few ApacheCons, we haven't managed to muster a
> track, or even a half day.
>
> To this end, we've started to put together a proposed list of talks that
> we'd like to see people submit, in the hopes that we end up with 2 days
> - a user track, and a developer track - of httpd content.
>
> https://public.etherpad-mozilla.org/p/httpd-apachecon-seville
>
> Please claim (and submit!) talks that appear on this list, and suggest
> others that we haven't thought of. Also, please plan to attend. The
> venue is beautiful and cheap, and it would be awesome to have a bunch of
> us there to do an old-school squash-the-bugs write-the-code
> meet-the-devs hackathon.
>
>
Ping to everybody in the list, if you have anything to add please check
https://public.etherpad-mozilla.org/p/httpd-apachecon-seville :)

Thanks!

Luca

Re: svn commit: r1759415 - /httpd/httpd/trunk/include/http_config.h

[Yann Ylavic]

On Tue, Sep 6, 2016 at 2:07 PM,   wrote:
> Author: ylavic
> Date: Tue Sep  6 12:07:39 2016
> New Revision: 1759415
>
> URL: http://svn.apache.org/viewvc?rev=1759415=rev
> Log:
> http_config: follow up to r1702948: maybe unused, yet maybe usefull too.

I get plenty of warnings compiling 2.4.x with recent gcc, like:

/home/yle/src/apache/httpd/2.4.x/include/http_config.h|429 col 24|
warning: ‘aplog_module_index’ defined but not used
[-Wunused-const-variable=]
||  static int * const aplog_module_index = &(foo##_module.module_index)
|| ^
/home/yle/src/apache/httpd/2.4.x/include/http_config.h|446 col 5|
note: in expansion of macro ‘APLOG_USE_MODULE’
||  APLOG_USE_MODULE(foo); \
||  ^~~~
/home/yle/src/apache/asf/httpd/httpd/branches/2.4.x/server/core.c|5314
col 1| note: in expansion of macro ‘AP_DECLARE_MODULE’
||  AP_DECLARE_MODULE(core) = {
||  ^

with several modules.

Maybe we could backport r1702948 (and this commit, which I think is a
better naming for the attribute) ?

Alternatively, if AP_MAYBE_UNUSED looks too (compiler) specific, the
following works for me too...

@@ -424,7 +426,11 @@ struct module_struct {
  */
 #define APLOG_USE_MODULE(foo) \
 extern module AP_MODULE_DECLARE_DATA foo##_module;  \
-static int * const aplog_module_index = &(foo##_module.module_index)
+static int * const aplog_module_index = &(foo##_module.module_index); \
+static APR_INLINE int aplog_foo##_module_index(void)  \
+{ \
+return aplog_module_index ? *aplog_module_index : -1; \
+}

This makes the static variable used in an inline function, which
itself may be unused but compilers do not warn about this
(usually...).

WDYT?