Re: [PHP-DEV] zend_timeout and the SIGPROF signal
I have a question in regards to page timeouts and how the initial I've noticed if a query takes longer than the default 30 seconds to execute, php returns a timeout message to the user. From what I can tell, php uses the SIGPROF signal to stop execution when the 30 seconds has expired. Also, I've found that it doesn't seem to unwind the stack I've reported it as bug #16820 and submited a patch, but no one answered ... I think it is better to use the same method as in Windows environment - set a EG(timeout) flag. regards, Wojtek -- PHP Development Mailing List http://www.php.net/ To unsubscribe, visit: http://www.php.net/unsub.php
Re: [PHP-DEV] zend_timeout and the SIGPROF signal
- Original Message - On timeout, the engine will call zend_bailout(), which performs a longjmp(). It does unwind the stack, but since we're dealing with C and not C++ and there are no destructors, it's your responsibility to clean after yourself. You can do it by properly registering your resources with PHP's infrastructure (using the Zend Engine memory management, resource management, etc.), which will be destroyed when the request terminates (in this case, shortly after the longjmp()). Doing this is a good idea (read: must) regardless of timeouts, it's the safety net that ensures that your code will not be leaking memory and/or resources beyond the context of a single request. Zeev It is impossible to do it in ZTS for malloc - it uses internal lock which is not a PHP resource. Long jump from signal causes that lock to be not released and we have beautiful deadlock ... Also when you use external library and it is modifying its internal structures when signal come, cleaning it is impossible (and dangerous). ZE shouldn't use zend_bailout in signal!!! regards, Wojtek -- PHP Development Mailing List http://www.php.net/ To unsubscribe, visit: http://www.php.net/unsub.php
Re: [PHP-DEV] zend_timeout and the SIGPROF signal
- Original Message - I looked into the bug report, and it is true that BLOCK_INTERRUPTIONS should indeed block SIGPROF. I'll fix this in the weekend. I'm not sure if after unblocking interruptions PHP will get SIGPROF ... it could cause long scripts. I'd rather use EG(timeout). I'm using it now and it's working. regards, Wojtek -- PHP Development Mailing List http://www.php.net/ To unsubscribe, visit: http://www.php.net/unsub.php
