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This topic contains 5 replies, has 3 voices.

Last updated by Diego Pereira 6 months, 1 week ago.

Assigned support staff: Diego Pereira.

Author Posts
March 6, 2019 at 9:01 pm #3281265

Richard

We were experiencing problems with our WP4.9.9 Multisite network becoming unresponsive, hanging up and crashing. After LOTS of research we discovered that clearing the caches would restore normal operation for a while.

Our developer was advised and when he dug in further, he discovered the following:

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The issue with WPML translation management plugin and the Redis Object Cache plugin was:

[05-Mar-2019 21:51:58 UTC] PHP Fatal error: Uncaught Exception: Serialization of 'Closure' is not allowed in /home/soobabiz/public_html/wp-content/object-cache.php:1146
Stack trace:
#0 /home/soobabiz/public_html/wp-content/object-cache.php(1146): serialize(Array)
#1 /home/soobabiz/public_html/wp-content/object-cache.php(846): WP_Object_Cache->maybe_serialize(Array)
#2 /home/soobabiz/public_html/wp-content/object-cache.php(227): WP_Object_Cache->set('932291', Array, 'WPML_TM_ICL_Tra...', 0)
#3 /home/soobabiz/public_html/wp-content/plugins/sitepress-multilingual-cms/classes/utilities/class-wpml-wp-cache.php(27): wp_cache_set('932291', Array, 'WPML_TM_ICL_Tra...', 0)
#4 /home/soobabiz/public_html/wp-content/plugins/wpml-translation-management/classes/records/class-wpml-tm-icl-translations.php(91): WPML_WP_Cache->set('93229', Array)
#5 /home/soobabiz/public_html/wp-content/plugins/wpml-translation-management/classes/filters/class-wpml-tm-translation-status.php(78): WPML_TM_ICL_Translations->translations()
#6 /home/soobabiz/public_html/wp-content/plugins/wp in /home/soobabiz/public_html/wp-content/object-cache.php on line 1146

I fixed it by adding the cache group WPML_TM_ICL_Translations::translations to the WP_REDIS_IGNORED_GROUPS array which makes it bypass the Redis caching mechanism.

Unless Translation management can be updated to prevent this, other users of Redis might need to know this because in our case it disrupted our entire network of 60+ sites multiple times until the root cause was determined and addressed.

March 7, 2019 at 8:05 pm #3286766

Dan

Richard, Thank you for reporting this. We are also experiencing an issue with Translation Management plugin that looks to be related to Redis (see https://wpml.org/forums/topic/difficulty-switching-to-see-posts-in-translation-management-panel/page/3/#post-3286759 )

If we were to do your fix ("adding the cache group WPML_TM_ICL_Translations::translations to the WP_REDIS_IGNORED_GROUPS") does that mean all translated pages will NOT be cached by Redis? I am just trying to understand the potential impact. Thanks.

March 8, 2019 at 2:15 pm #3293068

Diego Pereira
Supporter

Languages: English (English ) Spanish (Español ) Portuguese (Brazil) (Português )

Timezone: America/Sao_Paulo (GMT-03:00)

Hello @richard, welcome to the WPML support Forum!

Thank you very much for reporting the issue and the solution for it. I'm reporting it to our Dev team.

All the best,
Diego

March 25, 2019 at 12:05 pm #3453115

Diego Pereira
Supporter

Languages: English (English ) Spanish (Español ) Portuguese (Brazil) (Português )

Timezone: America/Sao_Paulo (GMT-03:00)

Hello @richard and @dan,

Could You give more details on how to reproduce this problem (server settings, steps, etc). Our developers are trying to reproduce the issue.

Kind regards,
Diego

April 11, 2019 at 10:53 am #3586411

Richard

Hi Dan,

I am not sure about the Redis implications you asked about.
I am not that familiar with Redis and we only began using it a short while ago, so not much experience at this time.

Diego,
I have no other information to provide at this time.
The issue was persistent until our developer reconfigured Redis as indicated.

Thanks,
Phil D

April 11, 2019 at 7:06 pm #3592299

Diego Pereira
Supporter

Languages: English (English ) Spanish (Español ) Portuguese (Brazil) (Português )

Timezone: America/Sao_Paulo (GMT-03:00)

Hi there,

Thank you for the feedback. I will forward to our dev team.

Kind regards,
Diego