The site was working fine until recently, the loading speed has dramatically increase, visitor get Internal 500 from time to time. First i thought it was the recent extension I installed, Marisvit Rewards, but after i disabled the extension, it is still very slow to load. Right now, i'm running out of ideas, below are what i done. Hopefully someone can direct me where to look into. Thank you.
- I am using SiteGround Cloud hosting 3 CPU with 8G RAM, and made sure .htaccess and .phi.ini memory_limit are correct
- I have use magento js and css merging, minify, and bundling to decrease the request from ~300 to ~100.
- I have enabled gzip compression
- I am using CDN from cloudflare
- I have enabled memcached
- I have cloned the exact site to develop.gofanco.com on the same hosting, installed the same extension ( without further js/css optimization & without CDN), even that it runs faster than my live site! very weird..
below is from gtmetrix: https://gtmetrix.com/reports/www.gofanco.com/wAMHMWR4 ( live site) https://gtmetrix.com/reports/develop.gofanco.com/FkZg8iIV ( test site)
below is output from magento profiler, i'm not exactly sure how to find the cause of the issue.