> I can think of two ways to acheive this (each of which may be absurd > given better knowledge of fs internals than I have): Either a > per-process switch disabling atime updates or a way to obtain a > read-only clone of a block device which can be mounted ro,noatime.
The latter will not work, at least not for FFS and probably not for any filesystem whose implementation was not specifically designed to support it. The problem is that the `read-only' device is changing behind the filesystem's back. Unless you mean a read-only *snapshot* of a block device, in which case you're basically back at snapshots, only at the block device level instead of the filesystem level. (Actually, looking at the existing snapshot support, it's not clear to me that's not exactly what it already is.) /~\ The ASCII Mouse \ / Ribbon Campaign X Against HTML mo...@rodents-montreal.org / \ Email! 7D C8 61 52 5D E7 2D 39 4E F1 31 3E E8 B3 27 4B