Incorrect file size?

[David Malone]

On Mon, Jun 23, 2008 at 12:19:28AM -0700, Jeremy Chadwick wrote:
> I've used SpamAssassin for a few years now, and I've never seen this
> happen (including during migration from RELENG_6 to RELENG_7, and
> between SpamAssassin versions (from 3.0 to 3.2.x).  I cannot even begin
> to imagine how that file reached such a size, which is why I believe the
> issue may be filesystem corruption.

I've seen spamassassin creating large sparse file regurally and do
other strang things like get the database into a state where it
spins if it trys to clean it out. That's even starting with a clean
database.

> There isn't any way to solve this problem.  The file, as far as dump is
> concerned, is indeed 3TB.

Dump does understand sparse files, but doesn't store them in the
most efficient way possible. Dumping a filesystem with a 1TB file
seems to use about 2GB.

	David.

# truncate -s 1T /var/tmp/bigfile
# dump 0Lf - /var | wc -c
  DUMP: Date of this level 0 dump: Mon Jun 23 09:50:50 2008
  DUMP: Date of last level 0 dump: the epoch
  DUMP: Dumping snapshot of /dev/ad4s3d (/var) to standard output
  DUMP: mapping (Pass I) [regular files]
  DUMP: mapping (Pass II) [directories]
  DUMP: estimated 2212849 tape blocks.
  DUMP: dumping (Pass III) [directories]
  DUMP: dumping (Pass IV) [regular files]
  DUMP: DUMP: 2212776 tape blocks
  DUMP: finished in 59 seconds, throughput 37504 KBytes/sec
  DUMP: DUMP IS DONE
 2265876480