Fragmentation on XFS

Rob Bosch robbosch at
Tue Feb 26 04:52:01 GMT 2008

> A local transfer needs --no-whole-file if you want it to use the rsync
> algorithm (which uses more disk I/O, so it's not the default).

Here are the stats on a small file...exactly as expected with everything
getting matched.  Is this an issue with how much of the file rsync can look
across to find a match?  I noticed the previous run had a huge number of
false_alarms and a negative number for hash_hits.  Does this point to where
the problem may be?


=== rsync -I --no-whole-file --port=888 -vv --compress-level=9 --stats
'/cygdrive/e/work data/temp/*' 'rsync://svcwrsync@' ===
opening tcp connection to port 888
sending daemon args: --server -vvIz --compress-level=9 . TestXFS
total: matches=11225  hash_hits=11225  false_alarms=1 data=0

rsync[360] (sender) heap statistics:
  arena:         524288   (bytes from sbrk)
  ordblks:            2   (chunks not in use)
  smblks:             0
  hblks:              0   (chunks from mmap)
  hblkhd:        655360   (bytes from mmap)
  allmem:       1179648   (bytes from sbrk + mmap)
  usmblks:      1966080
  fsmblks:            0
  uordblks:     1118544   (bytes used)
  fordblks:       61104   (bytes free)
  keepcost:       61040   (bytes in releasable chunk)

Number of files: 1
Number of files transferred: 1
Total file size: 125892318 bytes
Total transferred file size: 125892318 bytes
Literal data: 0 bytes
Matched data: 125892318 bytes
File list size: 27
File list generation time: 0.010 seconds
File list transfer time: 0.000 seconds
Total bytes sent: 81
Total bytes received: 78613

sent 81 bytes  received 78613 bytes  4496.80 bytes/sec
total size is 125892318  speedup is 1599.77

Execution time: 17.693 s

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