2010/4/15 Ferenc Kovacs <tyr...@gmail.com>: > > > On Thu, Apr 15, 2010 at 9:25 AM, Jérôme Loyet <jer...@loyet.net> wrote: >> >> 2010/4/15 Ferenc Kovacs <tyr...@gmail.com>: >> > >> > >> > On Thu, Apr 15, 2010 at 9:09 AM, Ferenc Kovacs <tyr...@gmail.com> wrote: >> >> >> >> >> >> 2010/4/15 Jérôme Loyet <jer...@loyet.net> >> >>> >> >>> 2010/4/15 滕路遥 <tly.phpf...@gmail.com>: >> >>> > We check error log after our server crashed, and we found that php >> >>> > heap >> >>> > memory is out of limit, >> >>> > so I think imagick use emalloc to allocate php heap memory, to check >> >>> > the >> >>> > zend_memory_usage is >> >>> > not a method for imagick, other circumstances which occupy huge >> >>> > memory >> >>> > can >> >>> > use this method to >> >>> > ensure the system have enough free memory. >> >>> >> >>> OK, >> >>> >> >>> one thing I didn't understand is "why should you want check de zend >> >>> memory usage when there is a memory_limit parameter in PHP.ini " ? >> >>> does'nt it do the same at PHP layer when allocating ? >> >>> >> >> >> >> Obviously you didn't read the original mail, and the links inside: >> >> >> >> >> >> http://groups.google.com/group/highload-php-en/browse_thread/thread/1882a3b2257dcc5c/ea73892cea011541?lnk=gst&q=gaochunhui#ea73892cea011541 >> >> >> >> The problem here is that PHP wouldn't free any allocated memory untill >> >> the process exits, so there's the risk of memory exhaustion if too >> >> many PHP processes were running, even though each process wouldn't >> >> exceed PHP's memory_limit. >> >> >> >> My suggestion is more about releasing the allocated memory as soon as >> >> possible. That is, this option is similar to "max_requests". >> >> >> >> PHP-FPM would kill the PHP process if the requests a process handled >> >> exceed max_requests, and similarly, PHP-FPM should kill the PHP >> >> process whose memory usage exceeds "exit_on_memory_exceeds". >> >> >> >> So one of your lib (for example imagick) leaks memory, on the long run, >> >> it >> >> will exhaust the memory limit, and will kill a totaly request. >> >> You can set that how many request should be served with one worker, but >> >> you can't soft limit it's memory consumption. >> >> This is what the patch does: >> >> if you set the hard limit: (memory_limit) you can guarante that no >> >> process >> >> will use more memory, because if it tries, it will fail. >> >> and you can set soft limit, if that reached, the process will die and >> >> respawn after finishing the current request. >> >> >> >> Tyrael >> > >> > Btw: did you know about >> > http://php.net/manual/en/function.apache-child-terminate.php I just >> > noticed >> > a few days ago, obviously, you can't use with cgi/fastcgi/php-fpm but >> > for >> > apache, it does exactly what you need, except that you have to execute >> > from >> > userland. >> >> This function is interesting but it's called from php scripts. When >> you are a sysadmin who host hundreds of different customers, you can't >> garanty each customer will call this function each time he uses >> consomption scripts. > > Yeah, I know, and I think I did mention that, but this sounds like a good > feature in the language, but sadly it has too many limitation in it's > current form. (no windows support, only works with apache)
I see how soft_limit could work (after processing a page, memory is checked and if it's more than the soft limit, the process is killed). But how can you make the hard_limit to work ? You'll have to setup memory check for each process by a master process, because the child won't be able to check it's memory realtime (or I missed something) ++ Jerome -- PHP Internals - PHP Runtime Development Mailing List To unsubscribe, visit: http://www.php.net/unsub.php
