On 9/1/06, apacheuser123@xxxxxxx <apacheuser123@xxxxxxx> wrote:
Hi,
I have an Apache 2.2.2 setup on a Redhat box. Caching is implemented using
mod_mem_cache.
Apache was built to use worker MPM. Here are the relevant sections from
httpd.conf
#
# mod_cache/mod_mem_cache settings
#
<IfModule cache_module>
<IfModule mem_cache_module>
CacheEnable mem /
CacheStoreNoStore On
MCacheSize 4096
MCacheMaxObjectCount 200
MCacheMinObjectSize 1
MCacheMaxObjectSize 524288
</IfModule>
</IfModule>
#
# Worker MPM settings
#
<IfModule mpm_worker_module>
StartServers 1
MaxClients 250
ThreadsPerChild 50
MinSpareThreads 25
MaxSpareThreads 75
</IfModule>
When I startup Apache, I notice there are multiple httpd( 1 parent and 2
child ) instances.
Question I had is,
1. Does this mean that at any time there are could be multiple memory
caches equal to the number of running
httpd instances ? or is the cache somehow shared between child processes ?
Yes, there is a separate cache for each child process.
2. How are requests handled ? For instance, do all requests go the first child process, till it has no more free threads at which point the the second child process is called into action ?
The allocation is essentially random depending on who is holding the accept mutex. You should really consider using mod_disk_cache instead. It uses a cache that is shared between all processes, and is often as fast or faster than mod_mem_cache because the OS can optimize the memory caching part. Joshua. --------------------------------------------------------------------- The official User-To-User support forum of the Apache HTTP Server Project. See <URL:http://httpd.apache.org/userslist.html> for more info. To unsubscribe, e-mail: users-unsubscribe@xxxxxxxxxxxxxxxx " from the digest: users-digest-unsubscribe@xxxxxxxxxxxxxxxx For additional commands, e-mail: users-help@xxxxxxxxxxxxxxxx
|