Otdfbt

I'm trying to get atomic deployments, I don't want to lose/drop any requests.

I deploy the code using Capistrano, classic situation were you have a 'current' dir that is a symlink to
the latest release in the 'release' folder.
I'm using Nginx, PHP 5.5 FPM with Opcache.
Following the idea of just using $realpath_root in Nginx I'm expecting that a simple nginx reload would suffice, but it's not.
With nginx reload it seems that I'm not losing any requests but php-fpm is still executing the code from the previous old dir.
If I do a 'php-fpm reload' then php fpm is reading from the new dir but I can still see that I'm losing some requests:

'recv() failed (104: Connection reset by peer) while reading response header from upstream'

The question is: should I reload PHP FPM or not?

From what I understand nginx is passing the path to php-fpm and from the nginx debug log I can see that the path passed is the right one but php-fpm still executes the old one.

2014/09/23 17:13:22 [debug] 26234#0: *1742 http script var: "/shop/www/htdocs/current/web"
2014/09/23 17:13:22 [debug] 26234#0: *1742 posix_memalign: 00000000010517A0:4096 @16
2014/09/23 17:13:22 [debug] 26234#0: *1742 http script copy: "SCRIPT_FILENAME"
2014/09/23 17:13:22 [debug] 26234#0: *1742 http script var: "/shop/www/htdocs/ive/releases/20140923124417/web"
2014/09/23 17:13:22 [debug] 26234#0: *1742 http script var: "/app.php"
2014/09/23 17:13:22 [debug] 26234#0: *1742 fastcgi param: "SCRIPT_FILENAME: /shop/www/htdocs/live/releases/20140923124417/web/app.php"
2014/09/23 17:13:22 [debug] 26234#0: *1742 http script copy: "DOCUMENT_ROOT"
2014/09/23 17:13:22 [debug] 26234#0: *1742 http script var: "/shop/www/htdocs/live/releases/20140923124417/web"
2014/09/23 17:13:22 [debug] 26234#0: *1742 fastcgi param: "DOCUMENT_ROOT: /shop/www/htdocs/live/releases/20140923124417/web"
2014/09/23 17:13:22 [debug] 26234#0: *1742 http script copy: "APPLICATION_ENV"

What am I missing? thanks

It sounds like you have made changes to the default OPcache configuration.

The defaults are:

opcache.validate_timestamps = 1
opcache.revalidate_freq = 2

This specifies whether and for how long OPcache should wait before checking to see if a file on disk has changed. In this case, yes, and after two seconds.

First, try re-enabling this option, as it sounds like you have turned it off.

I also faced that issue then finally I make a solution.

$ curl -sO http://gordalina.github.io/cachetool/downloads/cachetool.phar
$ chmod +x cachetool.phar

You can connect to a automatically guessed fastcgi server (if /var/run/php5-fpm.sock is a file or 127.0.0.1:9000)

apc
 apc:bin:dump Get a binary dump of files and user variables
 apc:bin:load Load a binary dump into the APC file and user variables
 apc:cache:clear Clears APC cache (user, system or all)
 apc:cache:info Shows APC user & system cache information
 apc:cache:info:file Shows APC file cache information
 apc:key:delete Deletes an APC key
 apc:key:exists Checks if an APC key exists
 apc:key:fetch Shows the content of an APC key
 apc:key:store Store an APC key with given value
 apc:sma:info Show APC shared memory allocation information
opcache
 opcache:configuration Get configuration information about the cache
 opcache:reset Resets the contents of the opcode cache
 opcache:status Show summary information about the opcode cache
 opcache:status:scripts Show scripts in the opcode cache

Example :

 [root@ip-172-31-5-244 ~]# php cachetool.phar opcache:status
+----------------------+---------------------------------+
| Name | Value |
+----------------------+---------------------------------+
| Enabled | Yes |
| Cache full | No |
| Restart pending | No |
| Restart in progress | No |
| Memory used | 42.71 MiB |
| Memory free | 85.29 MiB |
| Memory wasted (%) | 0 b (0%) |
| Strings buffer size | 8 MiB |
| Strings memory used | 5.31 MiB |
| Strings memory free | 2.69 MiB |
| Number of strings | 103847 |
+----------------------+---------------------------------+
| Cached scripts | 1261 |
| Cached keys | 2748 |
| Max cached keys | 7963 |
| Start time | Thu, 08 Feb 2018 02:28:56 +0000 |
| Last restart time | Thu, 08 Feb 2018 03:10:19 +0000 |
| Oom restarts | 0 |
| Hash restarts | 0 |
| Manual restarts | 1 |
| Hits | 47839 |
| Misses | 1269 |
| Blacklist misses (%) | 0 (0%) |
| Opcache hit rate | 97.415899649752 |
+----------------------+---------------------------------+
[root@ip-172-31-5-244 ~]#
[root@ip-172-31-5-244 ~]#
[root@ip-172-31-5-244 ~]# php cachetool.phar opcache:reset
[root@ip-172-31-5-244 ~]#
[root@ip-172-31-5-244 ~]#
[root@ip-172-31-5-244 ~]# php cachetool.phar opcache:status
+----------------------+---------------------------------+
| Name | Value |
+----------------------+---------------------------------+
| Enabled | Yes |
| Cache full | No |
| Restart pending | No |
| Restart in progress | No |
| Memory used | 10.43 MiB |
| Memory free | 117.57 MiB |
| Memory wasted (%) | 0 b (0%) |
| Strings buffer size | 8 MiB |
| Strings memory used | 545.69 KiB |
| Strings memory free | 7.47 MiB |
| Number of strings | 103847 |
+----------------------+---------------------------------+
| Cached scripts | 0 |
| Cached keys | 0 |
| Max cached keys | 7963 |
| Start time | Thu, 08 Feb 2018 02:28:56 +0000 |
| Last restart time | Thu, 08 Feb 2018 03:19:00 +0000 |
| Oom restarts | 0 |
| Hash restarts | 0 |
| Manual restarts | 2 |
| Hits | 0 |
| Misses | 2 |
| Blacklist misses (%) | 0 (0%) |
| Opcache hit rate | 0 |
+----------------------+---------------------------------+

You can notice that the memory , cache keys , hits everythings became 0 :-). Its very useful. I also intrigrated it with Ansible easily.

Its application for apcu and others stuffs : Check more there
http://gordalina.github.io/cachetool/