I'm running a fairly resource-heavy Magento-based site via a combination of Apache httpd, redis and php-fpm.
When I make changes to core PHP files, it's necessary to restart the above services to make sure no old code is cached which can (and does) screw up Magento.
In the past when I just used httpd, I simply ran
service httpd graceful to gracefully restart without affecting site visitors, but now that I have to restart several services (and flush redis) the website is unavailable for a few seconds.
Is it possible to avoid this?