httpd-dev mailing list archives

Site index · List index
Message view « Date » · « Thread »
Top « Date » · « Thread »
From Davi Arnaut <d...@haxent.com.br>
Subject Re: mod_cache responsibilities vs mod_xxx_cache provider responsibilities
Date Thu, 14 Sep 2006 11:09:25 GMT

On 14/09/2006, at 04:24, Niklas Edmundsson wrote:

> On Wed, 13 Sep 2006, Davi Arnaut wrote:
>
>> I'm working on this. You may want to check my proposal at http:// 
>> verdesmares.com/Apache/proposal.txt
>
> Will it be possible to do away with "one file for headers and one  
> file for body" in mod_disk_cache with this scheme?

http://verdesmares.com/Apache/patches/016.patch

>
> The thing is that I've been pounding seriously at mod_disk_cache to  
> make it able to sustain rather heavy load on not-so-heavy  
> equipment, and part of that effort was to wrap headers and body  
> into one file for mainly the following purposes:
>
> * Less files, less open():s (small gain)
> * Way much easier to purge old entries from the cache (huge gain).
>   Simply list all files in cache, sort by atime and remove the oldest.
>   The old way by using htcacheclean took ages and had less useful
>   removal criteria.
> * No synchronisation issues between the header file and body file,
>   unlink one and it's gone.
>
> That's only one of many changes made, but I found it to be crucial  
> to be able to have an architecture that's consistent without  
> relying on locks. This made it rather easy to implement stuff like  
> serving files that are currently being cached from cache, reusing  
> expired cached files if the originating file is found to be  
> unmodified, and so on.
>
> But the largest gain is still the cache cleaning process.
>
> The stuff is used in production and seems stable, however I haven't  
> had any response to the first (trivial) patch sent so I don't know  
> if there's any interest in this.
>
> /Nikke
> -- 
> -=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=- 
> =-=-=-=-
>  Niklas Edmundsson, Admin @ {acc,hpc2n}.umu.se      |      
> nikke@acc.umu.se
> ---------------------------------------------------------------------- 
> -----
>  Does the Little Mermaid wear an algebra?
> =-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=- 
> =-=-=-=


Mime
View raw message