How to determine which script is being executed in PHP-FPM process - fastcgi

Question

I am running nginx + php-fpm. Is there any way how can I know what is each of the PHP processes doing? Something like extended mod_status in apache, where I can see that apache process with PID x is processing URL y. I'm not sure if the PHP process knows the URL, but getting the script path and name will be sufficient.

Answer 1

After some googling hours and browsing PHP.net bug tracking system I have found the solution. It is available since PHP 5.3.8 or 5.3.9, but doesn't seem to be documented. Based on feature request #54577, the status page supports option full, which will display status of each worker separately. So for example the URL will be http://server.com/php-status?full and sample output looks like:
pid: 22816
state: Idle
start time: 22/Feb/2013:15:03:42 +0100
start since: 10933
requests: 28352
request duration: 1392
request method: GET
request URI: /ad.php?zID=597
content length: 0
user: -
script: /home/web/server.com/ad/ad.php
last request cpu: 718.39
last request memory: 1310720

Answer 2

PHP-FPM has a built in status monitor, though it's not as details as mod_status. From the php-fpm config file /etc/php-fpm.d/www.conf (on CentOS 6)
; The URI to view the FPM status page. If this value is not set, no URI will be
; recognized as a status page. By default, the status page shows the following
; information:
; accepted conn - the number of request accepted by the pool;
; pool - the name of the pool;
; process manager - static or dynamic;
; idle processes - the number of idle processes;
; active processes - the number of active processes;
; total processes - the number of idle + active processes.
; The values of 'idle processes', 'active processes' and 'total processes' are
; updated each second. The value of 'accepted conn' is updated in real time.
; Example output:
; accepted conn: 12073
; pool: www
; process manager: static
; idle processes: 35
; active processes: 65
; total processes: 100
; By default the status page output is formatted as text/plain. Passing either
; 'html' or 'json' as a query string will return the corresponding output
; syntax. Example:
; http://www.foo.bar/status
; http://www.foo.bar/status?json
; http://www.foo.bar/status?html
; Note: The value must start with a leading slash (/). The value can be
; anything, but it may not be a good idea to use the .php extension or it
; may conflict with a real PHP file.
; Default Value: not set
;pm.status_path = /status
If you enable this, you can then pass the path from nginx to your socket/port for PHP-FPM and you can view the status page.
nginx.conf:
location /status {
include fastcgi_params;
fastcgi_pass unix:/var/lib/php/php-fpm.sock;
}

Answer 3

cgi command line is more convinient:
SCRIPT_NAME=/status \
SCRIPT_FILENAME=/status \
REQUEST_METHOD=GET \
cgi-fcgi -bind -connect 127.0.0.1:9000

Answer 4

You can use strace to show the scripts being run - and many other things - in real time. It's pretty verbose, but it can give you a good overall picture of what's going on:
# switch php-fpm7.0 for process you're using
sudo strace -f $(pidof php-fpm7.0 | sed 's/\([0-9]*\)/\-p \1/g')
The above will attach to the forked processes of php fpm. Use -p to attach to a particular pid.
The above would get the scrip path. To get the urls, you would look at your nginx / apache access logs.
As a side note, to see the syscalls and which ones are taking longest:
sudo strace -c -f $(pidof php-fpm7.0 | sed 's/\([0-9]*\)/\-p \1/g')
Wait a while, then hit Ctr-C