Question Cache Operator Back to None

[Fillip H.]

I've made a change to the next version that should log the exception being thrown

 

[semprot]

Error Info
XenForo_Exception: No valid caching servers found. - library/DBTech/Optimise/Operator/Redis.php:58
Generated By: Unknown Account, Kemarin pada 9:22 PM

Stack Trace
#0 /home/xxxxxxxxxxx/public_html/library/DBTech/Optimise/Operator/Abstract.php(332): DBTech_Optimise_Operator_Redis->connect()
#1 /home/xxxxxxxxxxx/public_html/library/DBTech/Optimise/XenForo/Model/Thread.php(26): DBTech_Optimise_Operator_Abstract::createFromOptions('60')
#2 /home/xxxxxxxxxxx/public_html/library/XenForo/ControllerHelper/ForumThreadPost.php(154): DBTech_Optimise_XenForo_Model_Thread->getThreadById(1208252, Array)
#3 /home/xxxxxxxxxxx/public_html/library/XenForo/ControllerHelper/ForumThreadPost.php(76): XenForo_ControllerHelper_ForumThreadPost->getThreadOrError(1208252, Array)
#4 /home/xxxxxxxxxxx/public_html/library/XenForo/ControllerPublic/Thread.php(32): XenForo_ControllerHelper_ForumThreadPost->assertThreadValidAndViewable(1208252, Array, Array)
#5 /home/xxxxxxxxxxx/public_html/library/ChangeThreadStarter/ControllerPublic/Thread.php(7): XenForo_ControllerPublic_Thread->actionIndex()
#6 /home/xxxxxxxxxxx/public_html/library/XenForo/FrontController.php(351): ChangeThreadStarter_ControllerPublic_Thread->actionIndex()
#7 /home/xxxxxxxxxxx/public_html/library/XenForo/FrontController.php(134): XenForo_FrontController->dispatch(Object(XenForo_RouteMatch))
#8 /home/xxxxxxxxxxx/public_html/index.php(13): XenForo_FrontController->run()
#9 {main}

try
{
	$redis_info = $this->redis_read->info();
}
catch (Exception $e)
{
	throw new XenForo_Exception('No valid caching servers found.');// Line 58
}

Lot of free RAM

[yoo@main ~]# free -h
             total       used       free     shared    buffers     cached
Mem:          362G        75G       287G       5.4G       2.0G        24G
-/+ buffers/cache:        49G       313G
Swap:         8.0G         0B       8.0G

I think that must be temporary issue when connecting to Redis.

I have a suggestion.
What if when admin chooses a cache operator, there is a hidden option that stores the selected cache operator, let's call it "temp_cache_operator".
There is 1 new visible DBO option :

• Automatically retry to re-choose selected cache operator every X minutes, if cache is "none" because of exception.

So there is 1 new cron which will retry to set cache operator to "temp_cache_operator" (if enabled by admin), every X minutes.

So if there is temporary issue when using cache operator, it will be retried again every X minutes.

What do you think?

Thank you.

 

[Fillip H.]

Try modifying the relevant line to

throw new XenForo_Exception('No valid caching servers found. Redis error: ' . $e->getMessage());

and see if that throws up a better error message for you.

 

[semprot]

Ok so here is latest error after i updated the code

Error Info
XenForo_Exception: No valid caching servers found. Redis error: Redis server went away - library/DBTech/Optimise/Operator/Redis.php:59
Generated By: xxxxxxxxxxx, Today at 12:10 PM

Stack Trace
#0 /home/xxxxxxxxxxx/public_html/library/DBTech/Optimise/Operator/Abstract.php(332): DBTech_Optimise_Operator_Redis->connect()
#1 /home/xxxxxxxxxxx/public_html/library/DBTech/Optimise/XenForo/Model/Post.php(74): DBTech_Optimise_Operator_Abstract::createFromOptions('0')
#2 /home/xxxxxxxxxxx/public_html/library/XenForo/ControllerPublic/Thread.php(68): DBTech_Optimise_XenForo_Model_Post->getPostsInThread(1201567, Array)
#3 /home/xxxxxxxxxxx/public_html/library/ChangeThreadStarter/ControllerPublic/Thread.php(7): XenForo_ControllerPublic_Thread->actionIndex()
#4 /home/xxxxxxxxxxx/public_html/library/XenForo/FrontController.php(351): ChangeThreadStarter_ControllerPublic_Thread->actionIndex()
#5 /home/xxxxxxxxxxx/public_html/library/XenForo/FrontController.php(134): XenForo_FrontController->dispatch(Object(XenForo_RouteMatch))
#6 /home/xxxxxxxxxxx/public_html/index.php(13): XenForo_FrontController->run()
#7 {main}

 

[Fillip H.]

There you go then, Redis crashes on your server

 

[semprot]

There you go then, Redis crashes on your server

On process manager, I see redis server is still running.
And nothing interesting in /var/log/redis.log

 

[Fillip H.]

The first search result on Google ( Redis server went away * Issue #374 * phpredis/phpredis * GitHub ) says that having XDebug enabled can cause this issue.

PS: Processes can auto-restart, so just because it's currently running doesn't mean it didn't crash or didn't cause a problem somewhere.

The point is that this is a server-side problem and I can offer no help besides googling "redis server went away" and passing information along to you.

 

[semprot]

The first search result on Google ( Redis server went away * Issue #374 * phpredis/phpredis * GitHub ) says that having XDebug enabled can cause this issue.

PS: Processes can auto-restart, so just because it's currently running doesn't mean it didn't crash or didn't cause a problem somewhere.

The point is that this is a server-side problem and I can offer no help besides googling "redis server went away" and passing information along to you.

I've read it and i don't have xdebug.
I just switched from redis to APCu now.

I think redis is too confusing for me

You can close this thread. I will post a new one if i had issue with APCu.

 

[Fillip H.]

Amusingly, here @ DBTech we have the exact opposite problem. APCu, which should be a very simple and straightforward thing, causes segfaults in apache whereas Redis works rock solid

 

[semprot]

Amusingly, here @ DBTech we have the exact opposite problem. APCu, which should be a very simple and straightforward thing, causes segfaults in apache whereas Redis works rock solid

I tried to run APCu for 10 minutes without problem, and then memory usage jumped, page loads slowed down to the bottom, PHP almost crashed.
And now i disabled APCu.

Do you have special redis configuration in redis.conf?

I tried filecache, but it seems sometimes "Running Test: Fetch Cache" is failed.
I think it is because file lock race condition?

 

[Fillip H.]

Our redis configuration is 100% default.

 

[DragonByte Technologies]

Hello semprot,

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