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From "Christiaan Lamprecht" <christiaanw...@googlemail.com>
Subject Re: Shared memory
Date Wed, 22 Nov 2006 23:11:40 GMT
On 11/22/06, Brian McQueen <mcqueenorama@gmail.com> wrote:
> In an old thread dated October 9, with the subject "server config
> apr_table_t" there was some talk about this issue and it was mantioned
> that the server config structure is to be considered non-volatile.
> Did I get that right?

>>On 10/10/06, William A. Rowe, Jr. <wrowe@rowe-clan.net> wrote:
>>All of them.  Understand that all malloc()ed memory heap pages in most
>>kernels are shared but marked copy-on-write.  As soon as any forked
>>process (every httpd child worker process) touches one byte in those
>>pages, they get their own copy of the memory that's then modified.
>>
>>If you never write to pconf, then all child processes will continue to
>>share the same, single copy.  Until one writes to it, potentially
>>chewing up alot of memory if there are many processes and many small
>>changes in that pool.  That's why I say touching the global pools
>>such as pconf is just a bad idea.

Currently I'm using the server config but allocating my own memory
(i.e. non-APR) So this should work? Albeit potentially playing with
fire.


Thanks
Christiaan

Apologies for re-posting the snippet, if that's against etiquette

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