Hello, friends. I have an unresolved 504/502 error problem. This error occurs at certain hours. Ussually at 10 A.M and 5 P.M (Western Indonesian Time). This error is characterized by increasing memory in cpu, load avg, disk I/O and bandwidth. The website could be accessed again if reload the nginx. My apologize for this inconvenience.
I have checked the active plugins on my website, but nothing seems to be the problem. What is the solution? I thank you for all the answers, it would be priceless thing for me.
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