I am designing a filesystem to be implemented in FUSE. I have a question regarding what is allowed and best practice. There are 2 scenarios:
- User process calls
open(..., O_NOATIME).
Filesystem updates atime anyway. Is this safe? - User process calls
open(...)
withoutO_NOATIME.
Filesystem forgets to update atime. Is this safe?
Assume that new atime is written to disk only if also other important attributes have changed. Therefore sometimes an update may follow, sometimes not.
Filesystem would have no mount parameters for changing behaviour. Behaviour described above would be default and mandatory.