Does the PHP parser stop working over time?

Question

PHP

The parser works on Denver, written in PHP. It cycles through the sites from the file, takes the codes of these sites using file_get_contents, and performs certain actions. The fact is that approximately the first 200 sites are successful, and then everything goes to zero. I checked, took the failing sites after those 200 successful ones, put the failing ones at the top of the list, restarted, and everything worked as it should.
That is, the algorithm is correct, what could be the problem here?
No errors pop up, maybe it's in the memory.
Worth ini_set("max_execution_time", "0");

Answer 1

is there anything in the error log?
and in general, add the output to the screen of each sneeze of the file, then it will at least be clear what it breaks on

Answer 2

Check the error logs if there is something like this:

Fatal error: Allowed memory size of 134217728 bytes exhausted (tried to allocate 54 bytes)

then put:
ini_set('memory_limit', '-1');