rsync hangs on one big file

Solution 1:

rsync is known to have this kind of problem on huge files because of an inefficient algorithm for the internal hashes buffer.

You have to use the --block-size option with a big value. But current versions doesn't allow to use more than 128 kB. Some webpages tell to use --block-size=10485760 --protocol=29 but in my case it is refused by rsync.

• use version 29 or older
• or recompile after modification of the MAX_BLOCK_SIZE constant

Solution 2:

Take a look at the bug reports against rsync. Maybe file a new one. You can find those from https://rsync.samba.org/bugzilla.html

Whether here or in a bug report, you should provide more specifics. What version of rsync is on each end, what's your OS, and exactly what command are you using? Are the files and/or rsync transfer compressed? With what zlib version?

https://bugzilla.samba.org/show_bug.cgi?id=10518 and maybe https://bugzilla.samba.org/show_bug.cgi?id=10372 might be relevant. Also see http://www.anchor.com.au/blog/2013/08/out-tridging-tridge/