Why the long response of the site?

Question

PHP

The essence of the problem for the last 4 days the site began to respond for a long time, but at the same time the site’s admin panel works quickly and other sites on this server work, I think that the problem is in some kind of script that freezes, sometimes it can quickly enter the site, but most often you have to wait a minute or even two. Can anyone know how to track what is preventing the site from loading?

Answer 1

ctrl+shift+i in chrome
network tab shows which resource how long it takes to load

Answer 2

Looking for the problem step by step.
If it's about scripts, then comment out the entire code of the problematic page, see how a blank sheet will load, then remove comments block by block, in this way you can find a problematic piece of code that affects page loading. For example, it can be a long query to the database, or queries to the database in a loop, and other problems. There may also be an attempt to load remote scripts.

Answer 3

First, look at how things are with resources and processes on the machine. It may immediately turn out that the case, for example, is in the database, then go look for slow queries and tune the database. If the database is not the point and the study of processes and resources does not give anything useful, then either profile, or, as mentioned above, act by elimination.
You can start by looking for the fast-growing pages on the site and comparing them to the slow ones.

Answer 4

I noticed a strange dependence, yesterday the site was loaded in the evening for 20 seconds, today 2 minutes and so every time, why is this happening?