Xhprof makes it easy to profile PHP code. It is free and let's you easily find performance hogs (just filter by inclusive wall time).
One problem - it doesn't compile with PHP7.
I found this fork that did compile under PHP7 on debian 8 - https://github.com/longxinH/xhprof
This guy - https://github.com/longxinH - many thanks you let me keep xhprof and use it with the latest php version.
PS: there is also this fork - https://github.com/RustJason/xhprof/tree/php7 but it is quite outdated.
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