From:             scott dot php at scottrix dot co dot uk
Operating system: Linux
PHP version:      5.2.6
PHP Bug Type:     Performance problem
Bug description:  SSL code should use select.

Description:
------------
We have had some problems with CPU usage using PHP test scripts on some
systems at work.  Looking into the strace logs it appeared to be in a tight
loop doing lots of reads mostly getting an EAGAIN error.  Looking into the
problem further it seems there are two locations in the file
ext/openssl/xp_ssl.c that were causing these "loops".

at line 223 (approx):

     int retry = 1;

     do {
        nr_bytes = SSL_read(sslsock->ssl_handle, buf, count);
        if (nr_bytes <= 0) {
           retry = handle_ssl_error(stream, nr_bytes, 0 TSRMLS_CC);
           stream->eof = (retry == 0 && errno != EAGAIN &&     
SSL_pending(sslsock->ssl_handle));
        } else {
           /* we got the data */
           break;
        }
     } while (retry);


and the loop around the lines (429):

         if (n <= 0) {
            retry = handle_ssl_error(stream, n, 1 TSRMLS_CC);
         } else {
            break;
         }
 
They both involve SSL connections and I understand that one needs to be
very careful using select in this area since the socket is a layer away
from the SSL reading etc.  However, the openssl code does come with some
examples on how to do this and I have created a patch that seemed to help a
lot in our case that I thought someone who knows more about php internals
would like to look at and maybe incorporate to some extent into future
releases.  I will hopefully be able to attach the patch once I have
submitted the bug.


-- 
Edit bug report at http://bugs.php.net/?id=46685&edit=1
-- 
Try a CVS snapshot (PHP 5.2):        
http://bugs.php.net/fix.php?id=46685&r=trysnapshot52
Try a CVS snapshot (PHP 5.3):        
http://bugs.php.net/fix.php?id=46685&r=trysnapshot53
Try a CVS snapshot (PHP 6.0):        
http://bugs.php.net/fix.php?id=46685&r=trysnapshot60
Fixed in CVS:                        
http://bugs.php.net/fix.php?id=46685&r=fixedcvs
Fixed in CVS and need be documented: 
http://bugs.php.net/fix.php?id=46685&r=needdocs
Fixed in release:                    
http://bugs.php.net/fix.php?id=46685&r=alreadyfixed
Need backtrace:                      
http://bugs.php.net/fix.php?id=46685&r=needtrace
Need Reproduce Script:               
http://bugs.php.net/fix.php?id=46685&r=needscript
Try newer version:                   
http://bugs.php.net/fix.php?id=46685&r=oldversion
Not developer issue:                 
http://bugs.php.net/fix.php?id=46685&r=support
Expected behavior:                   
http://bugs.php.net/fix.php?id=46685&r=notwrong
Not enough info:                     
http://bugs.php.net/fix.php?id=46685&r=notenoughinfo
Submitted twice:                     
http://bugs.php.net/fix.php?id=46685&r=submittedtwice
register_globals:                    
http://bugs.php.net/fix.php?id=46685&r=globals
PHP 4 support discontinued:          http://bugs.php.net/fix.php?id=46685&r=php4
Daylight Savings:                    http://bugs.php.net/fix.php?id=46685&r=dst
IIS Stability:                       
http://bugs.php.net/fix.php?id=46685&r=isapi
Install GNU Sed:                     
http://bugs.php.net/fix.php?id=46685&r=gnused
Floating point limitations:          
http://bugs.php.net/fix.php?id=46685&r=float
No Zend Extensions:                  
http://bugs.php.net/fix.php?id=46685&r=nozend
MySQL Configuration Error:           
http://bugs.php.net/fix.php?id=46685&r=mysqlcfg

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