Re: [APC-DEV] Caching file_get_contents output inside APC (Performance improvement).

Hi,
   I did this effort to improve the specweb php performance improvement. I
can't of course change the php scripts to use APC specific functions to imp=
rove
specweb php performance improvement.

Here are few advantages :
* Similar to specweb php, I would expect many many php applications
will be using
  file_get_contents to load static content from php. We can't expect to mod=
ify
  these applications to improve their performance.
* Moreover modifying these applications to use APC functions makes them apc
  specific applications. These applications can't be run/tested without APC=
.
  (Application can test the apc availability dynamically but that is too mu=
ch
   to ask from applications).
* I downloaded 3 applications mediawiki, joomla and wordpress and found tha=
t
  all 3 applications uses file_get_contents. Even though these applications
  can use the mechanism described by piere, they don't. Unless APC is bundl=
ed
  inside php, it is very unlikely that these applications will make apc spe=
cific
  calls.  Adding this feature inside APC can benefit those users who uses t=
hese
  kind of applications.
* Cache can be turn on/off by configuration.


Whether or not this feature goes in APC depends on what we think about the
importance of file caching. If we think that file cache is a important aspe=
ct
and many many customers are using it then integrating and maintaining it in=
side
APC makes sense to me.

Inspiration behind this feature :
---------------------------------
    File cache is a integrated part of Sun Web Server (Originated from Nets=
cape
enterprise server). When jsp application includes a static file, Sun Web Se=
rver
serves the file from it's file cache.  Now I want to do the same thing for =
php
applications too. When php script loads a file, it should give an opportuni=
ty
to Web Server to serve content from it's file cache but unfortunately php
doesn't implement any such feature. Initially I tried to hook up the featur=
e in
php and was able to do so but hooking inside APC was much easier and much
cleaner because APC already provide APIs for storing content. I could also
write an extension to do so but then I have to re-implement mmap APIs what =
APC
already does.

Regards,
Basant.

On Wed, Oct 28, 2009 at 12:56 AM, shire <[email protected]> wrote:
>
> Hi Basant,
>
> Basant Kukreja wrote:
>
>> On Mon, Oct 26, 2009 at 2:14 PM, Pierre Joye <[email protected]> wrot=
e:
>>>
>>> (pseudo code where my_cache* could be either APC user cache, memcached
>>> or other caching lib like Cache_Lite)
>>> if (!($cached =3D my_cache_get($key))) {
>>> =A0$data =3D file_get_contents($path);
>>> =A0my_cache_add($data, $ttl);
>>> }
>>>
>>
>> =A0 =A0 Probably it will perform close to the version I attached but my
>> point is that application doesn't
>> need to be modified and can use this feature by modifying configuration.
>>
>> More options which I think of which can be used to extend the caching
>> feature :
>> apc.cache_max_file_size =A0 =A0# Maximum amount of files to be cached
>> apc.max_cache_use_bytes # Maximum amount of space to be occupied in cach=
e.
>>
>
>
> Thanks for the patch/suggested feature but I tend to agree with Pierre's
> suggestion for handling this in user space. =A0This is an extremely simpl=
e
> wrapper function to enable caching these values, and as your additional
> configuration items suggest, placing this functionality in APC creates so=
me
> unnecessary complications and less flexibility for the PHP developer.
>
> The intention of the APC user cache is to allow extending it in PHP user
> space for caching any number of items like this, using the very method
> Pierre suggested. =A0Heading in the direction you're suggesting would mea=
n
> that APC should be responsible for caching all sorts of stream and file
> based activities that PHP and even other extensions could perform without
> knowing enough about the data to do it in an intelligent way.
>
> Unless you can provide reasons why the APC extension in particular is in =
a
> situation to handle this better than anything else, I don't see a compell=
ing
> reason to start adding this type of functionality.
>
> -shire
>