How to catch a memory leak?

Question

PHP

There is a data import script whose memory consumption graph looks like this:

Although the algorithm is built on coroutines (each mini-peak is a new iteration), there is clearly a leak somewhere (or rather, someone fills the memory with side data). The problem is that the language is php 7.1, i.e. no obsolete xprof and memprof. Ideally, I would like to get a snapshot of all primitive zval containers at the beginning and at the very end, because such things are 146% affected by filling an array or string with data.
Any ideas?

Answer 1

It's hard to wang without code. It seems that in each iteration either a new variable is created and then not removed, or an element is added to the array, processed somehow, then the next element and so the array grows over time.

Answer 2

I looked at Dmitry's message and your comments - is it possible to find out the higher function that is above it? It's just logical that this piece of code will grow all the time, because There is a search of all values ​​and naturally the processing takes place at a higher level - you need to look there :)
UPD: And what did xdebug actually do not please?