Hi,
It's a well known PHP problem, that exceeding of execution time-out (max_execution_time) may lead to unexpected crashes. They occur because PHP may be interrupted in inconsistent state, and attempt to release allocated by request resources leads to failure. Almost any big site sees these crashes from time to time. I propose to delay actual request termination until a "safe" point in interpreter. Signal handler will just set EG(timed_out) flag. Interpreter will check this time from time to time (on jumps and calls that may make loops or recursion) and perform the actual termination. This approach already works in PHP for Windows. In addition I introduce hard_timeout (default value 2 seconds). In case the "soft" timeout wasn't handled "safely" in that 2 seconds (because of long running internal function), PHP process will be terminated without attempt to free any resources. ZTS build will ignore "hard_timeout" (in the same way as PHP on Windows do). The PR: https://github.com/php/php-src/pull/1876 It removes "exit_on_timeout" ini directive, and introduces "hard_timeout" instead. Additional checks in VM make 0.5-1% slowdown in term of instruction retired reported by callgrind. I think we don't need RFC for this. This is a long time desired fix. The same "interrupt" handling mechanism in the future may be reused for TICK and signal handling. Thanks. Dmitry.
