Originally Posted by raymor

To do it on purpose:
To do it explicitly you use the flag to open() as above. To do it accidentally and in a way that not only do your users not know you're doing it, but you yourself don't know you're doing it, you try to be as clever as you can with your caching. If your caching code is as "clever" as you can write, by definition you're not clever enough to understand all of it's side effects and you get clever but broken caching like nginx.



A patch to use O_NOATIME should be fairly trivial, but a module with no patch would be a little more involved because apr_file_open() doesn't currently pass flags directly to open(). Instead it ORs only the APR_* flags. One would need to make a trivial patch to apr_file_open(), then optionally pass O_NOATIME from a module based on configuration (or just use noatime always).