Messages in this thread |  | | Date | Wed, 13 Sep 2000 12:54:49 +0200 (CEST) | Subject | Re: NFS locking bug -- limited mtime resolution means nfs_lock() does not provide coherency guarantee | From | Trond Myklebust <> |
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>>>>> " " == Albert D Cahalan <acahalan@cs.uml.edu> writes:
> It would not be reasonable to try extending ext2 to 64-bit > times, but milliseconds might be doable. You'd need 4 bytes to > support the 3 standard time stamps.
> Going to microseconds would require 8 free bytes, which I don't > think we have. (but we do have more that one might think, due > to the unimplemented junk)
Don't forget that 2^20 > 10^6, hence if you really want units of microseconds, you actually only need to save 3 bytes worth of data per timestamp.
For the purposes of NFS, however the 'microseconds' field doesn't actually have to mean anything. It's just used as a cookie. Furthermore, only the mtime field, and to a limited extent the ctime field, are used for attribute consistency checking.
If NFS was the only concern therefore, you would get far on just saving one extra 24-bit field.
Cheers, Trond - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org Please read the FAQ at http://www.tux.org/lkml/
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