Re: Where exactly is the Perl interpreter?

["Jeffrey W. Baker" <jw...@acm.org>]

On Thu, 10 May 2001, Issac Goldstand wrote:

> I was just wondering- where exactly is the Perl interpreter in
> mod_perl 1.25 (for Apache 1.3) and where will it be in mod_perl 2
> (Apache 2.0)?  I assume in Apache 1.3 it's in shared memory, but I
> want to double check...

This depends strongly on how your platform works.  On Unix and friends,
the Perl interp is in each Apache process.  However, the various interps
may actually reside in the same physical memory on your computer, because
of a kernel feature called copy-on-write.  Look it up on Google if
interested.

It would be incorrect to say that Perl is in shared memory on Apache
1.3/Unix.  Although the memory may in fact be shared, it is not shared
memory in the sense of shmctl, shmget, and shmop(2).

-jwb

Re: Where exactly is the Perl interpreter?

[Stas Bekman <st...@stason.org>]

On Thu, 10 May 2001, Jeffrey W. Baker wrote:

>
>
> On Thu, 10 May 2001, Issac Goldstand wrote:
>
> > I was just wondering- where exactly is the Perl interpreter in
> > mod_perl 1.25 (for Apache 1.3) and where will it be in mod_perl 2
> > (Apache 2.0)?  I assume in Apache 1.3 it's in shared memory, but I
> > want to double check...
>
> This depends strongly on how your platform works.  On Unix and friends,
> the Perl interp is in each Apache process.  However, the various interps
> may actually reside in the same physical memory on your computer, because
> of a kernel feature called copy-on-write.  Look it up on Google if
> interested.

You may also try to look at my attempt to explain this:
http://perl.apache.org/guide/performance.html#Sharing_Memory

For 2.0 you want to read:
http://perl.apache.org/~dougm/modperl_2.0.html#perl

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