On Jun 25, 2007 19:15 +0530, Amit K. Arora wrote: > +#define FA_FL_DEALLOC 0x01 /* default is allocate */ > +#define FA_FL_KEEP_SIZE 0x02 /* default is extend/shrink size */ > +#define FA_FL_DEL_DATA 0x04 /* default is keep written data on DEALLOC */ In XFS one of the (many) ALLOC modes is to zero existing data on allocate. For ext4 all this would mean is calling ext4_ext_mark_uninitialized() on each extent. For some workloads this would be much faster than truncate and reallocate of all the blocks in a file. In that light, please change the comment to /* default is keep existing data */ so that it doesn't imply this is only for DEALLOC. Cheers, Andreas -- Andreas Dilger Principal Software Engineer Cluster File Systems, Inc. - To unsubscribe from this list: send the line "unsubscribe linux-fsdevel" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html