Re: php cli question

On Sat, Sep 11, 2010 at 8:50 PM, Shawn McKenzie <nospam@mckenzies.net> wrote: > On 09/10/2010 11:13 AM, J Ravi Menon wrote: >> Hi, >> >> I have some basic questions on running php  (5.2.x series on Linux >> 2.6) as a standalone daemon using posix methods (fork() etc..): >> >> #!/usr/bin/php >> <?php >> >> require_once ('someclass.php'); >> >> // do some initializations >> . >> >> // main 'forever' loop - the '$shutdown'  will >> // be set to true via a signal handler >> >> while(!$shutdown) >> { >>   $a = new SomeClass(); >> >>   $a->doSomething() >> >> } >> >> // shutdown logic. >> >> The 'someclass.php' in turn will include other files (via require_once). >> >> The above file will be executed directly from the shell. The main loop >> could be listening to new requests via sockets etc.. >> >> Few questions: >> >> 1) Does opcode cache really matter in such cli-based daemons? As >> 'SomeClass' is instantiated at every loop, I am assuming it is only >> compiled once as it has already been 'seen'. >>     I am not very clear on how apc (or eaccelerator) works in such cases. >> >> >> 2) What about garbage collection? In a standard apache-mod-php setup, >> we rely on the end of a request-cycle to free up resources - close >> file descriptiors, free up memory etc.. >>     I am assuming in the aforesaid standalone daemon case, we would >> have to do this manually?  In the loop above, would it be better to >> 'unset($a)' explicitly at the end of it before >>     it goes to the next iteration? >> >> Note: I have written pre-forker deamons in php directly and >> successfully deployed them in the past, but never looked at in depth >> to understand all the nuances. Anecdotally, I have >> done 'unset()' at some critical places were large arrays were used, >> and I think it helped. AFAIK, unlike Java, there is no 'garbage >> collector' thread that does all the magic? >> >> Thanks, >> Ravi > > If I have time when you reply I'll answer the questions, but I must ask: >  Is this purely academic?  Why is this a concern?  Have you encountered > issues?  If so, what? @Tom: I have compiled php with pcntl on and this has never been an issue. It works well (on a linux setup), and I have deployed standalone daemons with out any major problems. I have a home-grown 'preforker' framework (which I hope to share soon) which can be used to exploit multi-core boxes. @Shawn: It is not academic. There is a follow-up I am planning based on the doubts above. I have deployed such daemons in the past with some assumptions on (2) by doing manual cleanups - e.g. closing curl connections, closing up db handles etc... Really want to understand how php works in such setups outside of apache+mod_php. thanks, Ravi > > -- > Thanks! > -Shawn > http://www.spidean.com >