Bug #11344 Updated: Memory not being reused.

ID: 11344 Updated by: andi Reported By: brianlmoon@php.net Status: Feedback Bug Type: Scripting Engine problem Operating system: PHP Version: 4.0 Latest CVS (2001-06-08) Assigned To: Comments: Brian, Can you please checkout the latest CVS of PHP&Zend and let us know if this problem is fixed now? Thanks. Previous Comments: --------------------------------------------------------------------------- [2001-06-18 10:18:25] kalowsky@php.net marking this as feedback until reporter responds.... --------------------------------------------------------------------------- [2001-06-15 06:57:55] zeev@php.net Could you try to build PHP with fast_cache disabled and see what happens? Edit Zend/zend_fast_cache.h, and change # define ZEND_ENABLE_FAST_CACHE 1 to # define ZEND_ENABLE_FAST_CACHE 0 --------------------------------------------------------------------------- [2001-06-08 00:52:36] brianlmoon@php.net This is a follow up of sorts to: http://www.php.net/bugs.php?id=8889 I have been running some tests that do simple things to see what happens with the memory PHP uses in scripts. The simplest of these tests was a page with no PHP on it other than the code that logged the process memory usage: $PHP_PID = exec("echo $PPID"); $fp=fopen("/www/logs/user_log.20010607", "a"); fputs($fp, "memusaget$PHP_PID,".exec("ps -v -p $PHP_PID | awk '{print $8}'").",".time().",$HTTP_HOST,$REQUEST_URIn"); fclose($fp); I got interesting results. Although the growth of the process was small, it was obvoius that the memory was growing. Here is some sample data: PID MEM TIME 3019 3272 991952835 3019 3420 991952835 3019 3428 991952836 3019 3448 991952836 3019 3480 991952837 3019 3488 991952838 3019 3500 991952839 3019 3504 991952840 3019 3516 991952899 3019 3520 991952843 3019 3520 991952844 3019 3524 991952847 3019 3524 991952851 3019 3524 991952854 3019 3524 991952858 3019 3524 991952862 3019 3532 991952868 3019 3532 991952910 3019 3544 991952879 3019 3552 991952888 As I said it is not a large growth, but it is there. Now here is a script that creates an array over and over: for($x=0;$x<1000;$x++){ $arr[]=str_repeat("r", $x); } plus the code above that writes the log. Here are the results: PID MEM TIME 7322 3272 991953793 7322 3420 991953794 7322 3428 991953794 7322 3448 991953795 7322 3480 991953796 7322 3488 991953797 7322 3500 991953797 7322 3504 991953799 7322 3520 991953800 7322 3520 991953804 7322 3524 991953806 7322 3524 991953808 7322 3524 991953813 7322 3524 991953816 7322 3524 991953820 7322 3532 991953825 7322 3544 991953832 7322 3568 991953851 7322 3572 991953841 7322 3584 991953862 Again, a gradual growth occurs. Now, we put this into our production environment where we are running applications and we end up with: PID MEM TIME 31655 2656 991953822 31655 3124 991953826 31655 4012 991953833 31655 4560 991953839 31655 4956 991953858 31655 5020 991953877 31655 5256 991953879 31655 5312 991953880 31655 5348 991953889 31655 5900 991953903 31655 6132 991953904 31655 6392 991953904 31655 6664 991953917 31655 6944 991953933 31655 7204 991953938 31655 7256 991953940 31655 7556 991953941 31655 8404 991953943 31655 8548 991953950 31655 8692 991953968 31655 8880 991953976 31655 8880 991953981 31655 9148 991953990 31655 9400 991953992 31655 9608 991953994 31655 9608 991954006 31655 9788 991954021 31655 10156 991954023 31655 10424 991954029 Is there any explanation for any of this? I can live with PHP keeping and REUSING memory, but I don't want to have to think about how much memory my scripts take up because it never gets a)reused or b) returned to the system. If I wanted to worry about that stuff I would write in Perl or C. Brian. --------------------------------------------------------------------------- ATTENTION! Do NOT reply to this email! To reply, use the web interface found at http://bugs.php.net/?id=11344&edit=2