Apache restart needed after php code change

Question

When I change php code of an application I need to restart apache to make the new code effective.

$ sudo apachectl -l Compiled in modules: core.c mod_log_config.c mod_logio.c itk.c http_core.c mod_so.c 

It is a pretty stock Ubuntu configuration of Apache. I only installed mod_itk and created some vritualhosts.

Any ideas?

APC Support enabled Version 3.1.7 APC Debugging Disabled MMAP Support Enabled MMAP File Mask no value Locking type pthread mutex Locks Serialization Support php Revision $Revision: 307215 $ Build Date May 2 2011 19:00:42 Directive Local Value Master Value apc.cache_by_default On On apc.canonicalize On On apc.coredump_unmap Off Off apc.enable_cli Off Off apc.enabled On On apc.file_md5 Off Off apc.file_update_protection 2 2 apc.filters no value no value apc.gc_ttl 3600 3600 apc.include_once_override Off Off apc.lazy_classes Off Off apc.lazy_functions Off Off apc.max_file_size 1M 1M apc.mmap_file_mask no value no value apc.num_files_hint 1000 1000 apc.preload_path no value no value apc.report_autofilter Off Off apc.rfc1867 Off Off apc.rfc1867_freq 0 0 apc.rfc1867_name APC_UPLOAD_PROGRESS APC_UPLOAD_PROGRESS apc.rfc1867_prefix upload_ upload_ apc.rfc1867_ttl 3600 3600 apc.serializer default default apc.shm_segments 1 1 apc.shm_size 32M 32M apc.slam_defense On On apc.stat Off Off apc.stat_ctime Off Off apc.ttl 0 0 apc.use_request_time On On apc.user_entries_hint 4096 4096 apc.user_ttl 0 0 apc.write_lock On On 

Answer 1

You don't list us the PHP modules. You most likely have something like PHP Accelerator, XCache or similar in place, a front-end cache such as Varnish caching stuff or some other black magic you won't reveal us.

For the caches such as XCache, see their manual how to operate from this.

For the front-end caches such as Varnish, see their manual.

Other than that, it's hard to imagine what is actually caching your stuff.

Answer 2

The apc.stat option is turned off.

apc.stat Off Off 

In this case APC won't re-read cached files, ever.

The documentation states:

If this setting is off, APC will not check, which usually means that to force APC to recheck files, the web server will have to be restarted or the cache will have to be manually cleared.

To avoid restarting the web server, manually clear the cache by having the web server serve a PHP script containing only:

apc_clear_cache();