How to make big MySQL database more diffable/rsyncable? (aka rsyncing big files)

Martin Schwenke martin at
Tue Jul 7 21:15:18 GMT 2009

>>>>> "Krzysztof" == Krzysztof Nosek <krzysztof.nosek at> writes:

    Krzysztof> First, I was dumping the database with mysqldump to an
    Krzysztof> uncompressed dump and rsyncing it. Such a dump would
    Krzysztof> use some 34G of disk space. [...]

Some simple suggestions in addition to the one about experimenting
with block size:

* Does the output of mysqldump compress well with gzip?

  If so, you could try compressing it with a version of gzip that
  supports the --rsyncable option.  The version in Debian or Ubuntu
  Linux supports this option.

* If you're confident that you have a good line-oriented dump, how
  does diff cope when comparing 2 dumps?

  rsync and diff obviously use very different schemes for figuring out
  what is different.  However, sometimes doing a diff will show you
  something obvious that you have missed.  Obviously you'll need 68GB
  of free disk to be able to try that!

* If you're not telling rsync to transfer just a single file, do the
  filenames match at both ends of the transfer?

  You not doing something like creating a dump with the date in the
  filename, are you?

Sorry, no rocket science there...  ;-)

peace & happiness,

More information about the rsync mailing list