3 ms·
FWIW, 1. This is no longer true in rsync-3.0.0 (Mar 2008) and later. It does build the list of course, but transfer begins after establishing just a few direct
by quesera 5y ago
FWIW,
1. This is no longer true in rsync-3.0.0 (Mar 2008) and later. It does build the list of course, but transfer begins after establishing just a few directories of content. This "incremental" mode is not available if you specify an option that requires the full list to begin, documented under the "--recursive" option.
2. Checksums are not computed by default. If the files match time/size, they will not be transferred or checksummed unless "--checksum" is turned on. All files which are transferred, are compared by checksum when complete but this is not meaningfully expensive since the IO is already done.
Your issues with high-bandwidth, (very) high-latency links make sense. The rsync algo was designed to minimize bytes-sent over the undersea cable to Australia (low-bandwidth, moderate-latency). This still works well for most internet traffic, but not if your latency numbers are way out of balance!