ID: 26577 User updated by: vijolicni dot oblak at gmx dot net Reported By: vijolicni dot oblak at gmx dot net Status: Open Bug Type: Strings related Operating System: Windows 2003 PHP Version: 4.3.4 New Comment:
- On the server the script is going to run the script execution just ended with FATAL: emalloc() : Unable to allocate 418kB bytes - On my local computer the swapfile utilisation was so high that the script wan't able to save a 500kB file to a file and exit in 8 seconds (the saving function started at 22seconds since the start and ran into 30s limit) [sovertime= start_overtime, and parameter 8 means that it should save result and end execution at 22seconds, not to reach the 30s limit] Previous Comments: ------------------------------------------------------------------------ [2003-12-10 06:54:35] alex at pc4p dot net As a personal sidenote, I find your code highly inefficient and thus it is no wonder, that you reach the limits on your system. You should definetly read up on PREGs and http://www.php.net/preg_replace which is much faster than str_replace. str_replace should only be used for small strings and small replacements, larger tasks are the domain of regular expressions. Btw. I doubt, that this behaviour is being seen as a bug... ------------------------------------------------------------------------ [2003-12-10 06:30:40] vijolicni dot oblak at gmx dot net Description: ------------ There is obviously some kind of tracing of what happens to variables through their lifetime � a kind of optimization, I guess. But there is a problem when doing str_replace on large html files (more than 600kb): memory usage jumps from 350MB to 1.8GB according to Windows Task Manager performance monitor. My computer has 512MB physical memory and having more that one gigabyte of quickly changing data in swap file doesn�t help performance at all. It renders my system to almost unresponsive. I solved the problem by doing some �disoptimizations�: I put the contents of variable $htmlfile, that str_replace was done on to a new variable $tempvar, then I unset($htmlfile), and then reestablish $htmlfile as a new variable with $tempvar as it contents and continue execution where ended [�case� is used as a �goto� statement]. The set-unset code is commented. The solution to the problem should be that Zend Engine or whatever module is responsible for string tracing and/or memory management should check how much !physical! memory is available and never waste more that hundred(s) of available !physical! MBs on a script, but it should never run into swap file memory gigabytes for �optimizations�. [I have my swap file on Windows2003 set to 4GB if this is of any relevance] Reproduce code: --------------- $htmlfile=str_replace("\t",' ',$htmlfile); //if (sovertime(8)) savestate($destfilename,$htmlfile,10); return outr(10); case 10: while ($pos=strpos($htmlfile,' ')) { $htmlfile=str_replace(' ',' ',$htmlfile); if ($pos===false) break;} //if (sovertime(8)) savestate($destfilename,$htmlfile,20); return outr(20); case 20: while ($pos=strpos($htmlfile,"\r\n\r\n")) { $htmlfile=str_replace("\r\n\r\n","\r\n",$htmlfile); if ($pos===false) break;} //if (sovertime(8)) savestate($destfilename,$htmlfile,30); return outr(30); case 30: while ($pos=strpos($htmlfile,"\r\n ")) { $htmlfile=str_replace("\r\n ","\r\n",$htmlfile); if ($pos===false) break;} //if (sovertime(8)) savestate($destfilename,$htmlfile,40); return outr(40); case 40: while ($pos=strpos($htmlfile," \r\n")) { $htmlfile=str_replace(" \r\n","\r\n",$htmlfile); if ($pos===false) break;} $htmlfile=str_replace('<table ','<table width=100% ',$htmlfile); $htmlfile=str_replace('<TABLE ','<TABLE width=100% ',$htmlfile); $htmlfile=str_replace('<table>','<table width=100%>',$htmlfile); $htmlfile=str_replace('<TABLE>','<TABLE width=100%>',$htmlfile); //if (sovertime(8)) savestate($destfilename,$htmlfile,105);return outr(105);case 105: $htmlfile=str_replace('Š','�',$htmlfile); $htmlfile=str_replace('š','�',$htmlfile); $htmlfile=str_replace('Č','�',$htmlfile); $htmlfile=str_replace('č','�',$htmlfile); $htmlfile=str_replace('Ž','�',$htmlfile); $htmlfile=str_replace('ž','�',$htmlfile); //if (sovertime(8)) savestate($destfilename,$htmlfile,110);return outr(110);case 110: $htmlfile=str_replace('<table>','<table width=100%>',$htmlfile); $htmlfile=str_replace('<TABLE>','<TABLE width=100%>',$htmlfile); $htmlfile=str_replace('background:','bx:',$htmlfile); $htmlfile=str_replace('mso-highlight:','bx:',$htmlfile); $htmlfile=str_replace('text-align:justify','text-align:left',$htmlfile); Expected result: ---------------- Usage of only of available physical RAM as a tempspace for optimizations. Actual result: -------------- Usage of only of more than 1GB of swapfile as a tempspace for 'optimization' of a script. ------------------------------------------------------------------------ -- Edit this bug report at http://bugs.php.net/?id=26577&edit=1
