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Date: Wed, 11 Mar 2015 15:23:09 -0700
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Subject: Re: [PHP-DEV] Safe execution timeout handling
From: smalyshev@gmail.com (Stanislav Malyshev)

Hi!

> Instead of throwing zend_error() from signal handler, now we just set
> EG(vm_interrupt) and EG(timed_out) flags. PHP VM checks EG(vm_interrupt)
> flag on each JMPx instruction (potential loop iteration) and then throws

That looks very nice but makes timeouts much less powerful. I think
without some ability to interrupt internal functions it won't be good.

> Unfortunately this approach doesn't support interruption of long-running
> internal functions yet. It should be extended in some way. May be
> additional timeout.

Doing additional setjmp when entering internal function probably would
be too expensive. So the question is how to get out of the bad function
without incurring per-function overhead... Not sure how to do it.

-- 
Stas Malyshev
smalyshev@gmail.com