httpd-dev mailing list archives

Site index · List index
Message view « Date » · « Thread »
Top « Date » · « Thread »
From "Ralf S. Engelschall" <...@engelschall.com>
Subject Re: [PATCH] Shared Memory Pools ;-)
Date Tue, 26 Jan 1999 11:47:41 GMT

In article <36ADA765.C68135E6@urc.ac.ru> you wrote:
> "Ralf S. Engelschall" wrote:

>> > I suppose the answer to my first statement is, that a module during its
>> > non-child initialization phase allocates the pool and all of its children end
>> > up with a copy of that pool pointer.
>>
>> Correct. That's what my mod_test I posted does.  But usually the pointer is
>> then stored in a module configuration structure and not in a global variable,
>> of course.

> Could you please make the present situation (at least in 1.3.4) clear?

> Now, if I allocate a large (up to a megabyte) pool in the "create_server_config"
> phase (before the server get forked), fill up the pool with some data, and then use
> those data read-only while processing requests,  do the data duplicate for each
> server process (or request)? I don't mean any OS page management case (all is OK
> with it in FreeBSD which I use), just Apache's pool management behaviour.

Apache has only one copy of the configuration data and it's not duplicated.
And as long as you use it read-only it will even be kept as a single copy
physically in memory (copy-on-write by the OS).

                                       Ralf S. Engelschall
                                       rse@engelschall.com
                                       www.engelschall.com

Mime
View raw message