Tumn1s

1.11 does not fix the issues, but it does give you the advanced option I described above. As a follow up, it should be noted that after my site generated all of the cache files… my server CPU usage finally settled around 30%. That’s with the cache delay time set to 4h. I’m going to see if I can get better results by setting it higher.

If someone wants to try to fix this, the functions and scripts for generating the cache are in these files in the plugin directory:

\lib\strategy\class-ai1ec-persistence-context.php
\lib\strategy\cache_strategy\class-ai1ec-apc-cache.php
\lib\strategy\cache_strategy\class-ai1ec-db-cache.php
\lib\strategy\cache_strategy\class-ai1ec-file-cache.php
\app\helper\class-ai1ec-events-helper.php
\app\helper\class-ai1ec-events-list-helper.php

PROBLEM IDENTIFIED and Temporary Working Fix: The plugins’ internal caching mechanism is to blame for the high CPU and Memory usage. I fixed my problem by going to the plugin menu to settings -> advanced -> advanced settings and changing the cache flush interval from 5 minutes (5m) to 3 hours (3h). You can use whatever setting you like, just make sure it’s much longer than 5 minutes.

I found the problem when I was rolling back my calendar to version 1.82. While backing up my current plugin folder using version 1.11, I noticed that the cache folder contained over 4,800 files and was nearly 400mb in size. My guess is that the caching mechanism has a bug and loops, causing the plugin to constantly regenerate cache files for each view type, for each category, and for each post/event. Each minute, the plugin was generating nearly 250 new cache files, or about 4 per second. It doesn’t seem to have flushed any of the old ones, because if it did, I wouldn’t have over 4,800 files with unique file names. If you have a lot of calendar events, this REALLY slows down your site and hogs resources. By setting the calendar to flush the cache every 3 hours, it will not continuously use these resources.

After the change, my cache folder is generating between 5-7 files per minute… much lower than 250 per minute. Having said that, I can’t tell if it’s purging old cache files when it generates new ones, as it’s not gone through all of my views, categories, or events yet… I’ll let you know what I find out.

The good news, doing this dropped my CPU usage from over 90% to less than 15%. Memory usage dropped by almost half, from 1.95 GB to 1.1 GB including cache/buffers.

My setup is as follows:

Linode 2GB VPS
Nginx 1.41
Percona SQL Server using XtraDB
PHP-FPM 5.4 with APC caching db requests and opcode via W3 Total Cache
Wordpress 3.52
All in One Event Calendar 1.11