Caching Filehandles (seen some light!!)

[Anthony Gardner <cy...@yahoo.co.uk>]

Just realised, I could use Apache::Cache. Is there an MP2 version? Couldn't find one.



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Re: Caching Filehandles (seen some light!!)

[Jonathan Vanasco <mo...@2xlp.com>]

On Jan 4, 2007, at 11:44 AM, Perrin Harkins wrote:

> There's probably not much benefit from caching filehandles if you  
> still have to read the files anyway.  The best thing to do would be  
> to port to a more mature templating system.  Short of that, caching  
> the templates in memory (just in a hash, not in a shared cache like  
> the ones above) will give the biggest performance boost.

Agreed.

Using the filesystem handles as you described would actually be  
detrimental -- aside from the fact that you still have to read the  
files , you're looking at a lot of read/write on the memory related  
to the files -- on a per child basis.  If you've got a single class  
handling it with a single variable, figure that you're going to  
consume memory representing the largest file you'll be reading -- per  
child.  A lot of caching optimizers I've seen will store data in a  
string that is md5(file) --  which means you can have a var per file,  
per child -- which is a lot.

I'd strongly suggest to cache the files into memory at server start  
so that they're shared by all the children.  If you need something  
quick, just create a class to manage 'reading' files that stores the  
data into a md5( /path/to/file ) variables on startup, and returns a  
ref to the string as needed.  shouldn't take more than 30minutes to  
implement on the trickiest system.

// Jonathan Vanasco

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Re: Caching Filehandles (seen some light!!)

[Perrin Harkins <pe...@elem.com>]

Anthony Gardner wrote:
> Just realised, I could use Apache::Cache.

Don't use that.  The shared memory implementation is really slow.  If 
you need a cache, use Cache::FastMmap.

A cache of this kind is not what you need for this though.  You can't 
stuff filehandles into it.

There's probably not much benefit from caching filehandles if you still 
have to read the files anyway.  The best thing to do would be to port to 
a more mature templating system.  Short of that, caching the templates 
in memory (just in a hash, not in a shared cache like the ones above) 
will give the biggest performance boost.

- Perrin