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View Full Version : Pls Help on Datastore cache


rastler
02-07-2007, 11:54 AM
Hi,

When I went through Datastore class in vb 3.5, I found that their are 3 ways of caching

1)using Filecache
2)Using Memcache
3)Using Eaccelerator

Currently I am using Eaccelerator only for caching php scripts and filecaching. When we install eAccelarator it caches all PHP scripts accessed., What is the use of vb_eaccelarator extended class in VB ?

In includes/config.php, Under caching configuration we have Array variables settings for

filecache , memcache but not for eaccelarator , why ?

can I use eAccelarator for both caching scripts as well as datastore of VB?

or is it better to use this way

caching scripts - >Eaccelarator
Datastore - > Filecache and Memcache

It would be helpful for me for any inputs

Thanks
Rastler

Marco van Herwaarden
02-08-2007, 07:19 AM
If i remember correct, using eAccelerator for datastore caching is disabled in vBulletin as eAccelerator seem to be buggy with caching dynamic data.

See includes/class_datastore.php:
// ################################################## ###########################
// eAccelerator

class vB_Datastore_eAccelerator extends vB_Datastore
{
/*
Unfortunately, due to a design issue with eAccelerator
we must disable this module at this time.

The reason for this is that eAccelerator does not distinguish
between memory allocated for cached scripts and memory allocated
as shared memory storage.

Therefore, the possibility exists for the administrator to turn
off the board, which would then instruct eAccelerator to update
its cache of the datastore. However, if the memory allocated is
insufficient to store the new version of the datastore due to
being filled with cached scripts, this will not be performed
successfully, resulting in the OLD version of the datastore
remaining, with the net result that the board does NOT turn off
until the web server is restarted (which refreshes the shared
memory)

This problem affects anything read from the datastore, including
the forumcache, the options cache, the usergroup cache, smilies,
bbcodes, post icons...

As a result we have no alternative but to totally disable the
eAccelerator datastore module at this time. If at some point in
the future this design issue is resolved, we will re-enable it.

We still recommend running eAccelerator with PHP due to the huge
performance benefits, but at this time it is not viable to use
it for datastore cacheing. - Kier
*/
}

rastler
02-09-2007, 10:12 AM
Hi, Thanks for the info...

If I enable what could be the problem, I didn't get this sentence properly...
In the comment...
"Therefore, the possibility exists for the administrator to turn
off the board, which would then instruct eAccelerator to update
its cache of the datastore."

So eAccelarator is better only for opcode caching , So it would be better use Memcache for with caching dynamic data ?

Zia
03-03-2007, 06:07 AM
try with Xcache. As a opcode cacher its doing good &
data store cacher
https://vborg.vbsupport.ru/showthread.php?t=141005