Trying to use XCache -- Could Use Some Help!

[RedTurtle]

I am trying to setup XCache to run on my forum.

I am on my own server and installed XCache via WHM's EasyApache.

I then changed my includes/config.php to have the following in it:

$config['Datastore']['class'] = 'vB_Datastore_XCache';

I also see that in my php.ini, XCache has the following settings:

extension="xcache.so"
xcache.admin.enable_auth="on"
xcache.admin.pass=""
xcache.admin.user="mOo"
xcache.cacher="On"
xcache.coredump_directory=""
xcache.count="1"
xcache.coveragedump_directory="/tmp/pcov/"
xcache.coverager="Off"
xcache.gc_interval="0"
xcache.mmap_path="/dev/zero"
xcache.optimizer="Off"
xcache.readonly_protection="Off"
xcache.size="0"
xcache.slots="8K"
xcache.test="Off"
xcache.ttl="0"
xcache.var_count="1"
xcache.var_gc_interval="300"
xcache.var_maxttl="0"
xcache.var_size="0"
xcache.var_slots="8K"
xcache.var_ttl="0"

I get the following error:

Fatal error: Storing of variables is not enabled within XCache in [path]/includes/class_datastore.php on line 533

Also, I did set a unique datastore prefix in my config.php. I am guessing that my xcache settings in my php.ini are off...or maybe something else is up?

I'm on vB 4.2.1 and not sure how to proceed. I would like to see the benefits of XCache but as soon as I switch to XCache in my config.php I get this error.

Could anyone help out please? I'm on my own box so can change settings as needed.

Thank you.

[findingpeace]

Change these settings to the following values:

xcache.var_size  =            3M
xcache.var_count =             2
xcache.var_slots =            8K
xcache.var_ttl   =             7200
xcache.var_maxttl   =          14400
xcache.var_gc_interval =     300

[RedTurtle]

Thank you findingpeace!

That has removed the error and allows the pages to load. Do you know what each one of those values is based upon? Does it depend on server configuration, or whether or not I am using vBSEO (I am)?

I'm also using vBOptimize for our caching and when I go into the vB Optimize System Test where it checks the caching configuration it tells me that it is able to connect to xcache, and is able to store cache, but fails on the "fetch cache" part of the test.

The error it gives is: " Your XCache installation is not configured correctly. This is not a bug in vB Optimise, it's a problem with your server's configuration."

Any idea what could be wrong on my box that is keeping vB from fetching from xcache? I am thinking others may have the same issue but may never know it if they don't have vB Optimize installed which breaks down the test of it into each segment.

Also it seems that in admincp anytime I try to save any setting for any part of the control panel, I only get a blank white screen and the setting is not saved.

Thank you for any help.

[findingpeace]

Hmm RedTurtle, I'm not familiar with vBSEO, but I don't think vBSEO vs. vanilla vB should have any sort of impact on what your server-side cache settings should be.

Try: 1) Temporarily disable the vB Optimize mod, 2) Clear System Cache

Then let me know if the white screen issue stops! We can troubleshoot from there

[RedTurtle]

Thank you again for the quick reply.

Steps I've taken:

-Disabled plugins via config.php
-Disabled vBOptimise via AdminCP products page
-Cleared System Cache

The white screen is gone now, however if I turn vBOptimise back on, the problem persists again. On my current production box I am using Memcached and have tried to switch to XCache on this new test site. To this end I tried to clear the cache before I made my backup database which I imported onto the test server. I then changed the config.php from Memcached settings to XCache.

But for some reason I'm still not able to have xcache fetch the cache from the server.

Oh also, I went ahead and set a user/pass in the vbOptimise config file for accessing XCache since I noticed my XCache had authentication turned on.

Thank you again.

[findingpeace]

Ok, sounds like it's definitely related to vBOptimise, not vBSEO. If I were you, I'd pop by the official mod page:

https://vborg.vbsupport.ru/showthread.php?t=284816

Filip has always been really helpful whenever I ask questions!

[RedTurtle]

Thanks for listening to my strange issues. :P

Want to update this thread so that someone else in the future may be able to benefit from it.

It looks like XCache is not compatible with suPHP. If your server is running the apache suPHP module then XCache can't work.

To this end I have switched from suPHP to running php as FastCGI with mod_fcgid.

I am now able to get to the fetching cache part but still am having issues with flushing.

Will keep working on it and will try to ask DBTech for some help as well.

Thank you.

[Zachery]

Just having xcache installed and configured for php already increased your sites speed. You don't explicitly need it to cache the datastore. Though DBT's stuff will make better use of xcache than vBulletin will out of the box.

[RedTurtle]

Thank you Zachery. You make a great point.

I did get everything working. I was making a pretty newbie mistake by not restarting apache every time after editing php.ini.

I was able to turn xcache authentication off, and restarted apache and everything is working now and vBOptimise's xcache system test is functioning properly.

Even though I had configured vBOptimise to use the xcache username and password, and configured the vBOptimise config.php to have the correct username and password, it still wasn't working properly.

Just turning off xcache authentication in the php.ini file and restarting apache fixed the issue.

Thank you to everyone who helped!