Here's how it works in my 2 computers. First, on auk2 # rsync -a auk1::pub/linux.iso . It takes about 4 minutes. Everything is fine. However, after doing this on auk1, # echo "hello" >> /pub/linux.iso Then, on auk2 # rsync -a auk1::pub/linux.iso . The execution time of the first command is still 4 minutes. I think it's supposed to be much shorter than the first case? The same results appear in local rsync, too. Is there anything wrong with my commands? thanks in advance Andy
On Mon, Aug 04, 2003 at 10:55:55AM +0800, AndyWu wrote:> Here's how it works in my 2 computers. > > First, on auk2 > # rsync -a auk1::pub/linux.iso . > It takes about 4 minutes. Everything is fine. > > However, after doing this on auk1, > # echo "hello" >> /pub/linux.iso > > Then, on auk2 > # rsync -a auk1::pub/linux.iso . > > The execution time of the first command is still 4 minutes. > I think it's supposed to be much shorter than the first case? > The same results appear in local rsync, too. > Is there anything wrong with my commands?Unlikely. I'll bet that file is several hundred megabytes. Rsync has been known that have some difficulty with checksum collisions on files that large. If you run with -vv i'll bet it will report "redoing linux.iso(0)" or something very similar. With released versions of rsync this is avoidable to some degree with the --block-size option. At one time someone produced a list of suitable block/file sizes. Search the archives if this matters to you. This problem has already been addressed in CVS. -- ________________________________________________________________ J.W. Schultz Pegasystems Technologies email address: jw@pegasys.ws Remember Cernan and Schmitt
On Mon, 4 Aug 2003 12:55, AndyWu wrote:> Here's how it works in my 2 computers. > > First, on auk2 > # rsync -a auk1::pub/linux.iso . > It takes about 4 minutes. Everything is fine. > > However, after doing this on auk1, > # echo "hello" >> /pub/linux.iso > > Then, on auk2 > # rsync -a auk1::pub/linux.iso . > > The execution time of the first command is still 4 minutes. > I think it's supposed to be much shorter than the first case? > The same results appear in local rsync, too. > Is there anything wrong with my commands? >Andy, I'm no expert on the use of this excellent program, but there is some overhead incurred when the client initiates a transfer. Checksums have to be calculated and sent to the server before any transfer starts. FWIW I corrected a ~700meg iso in Australia from a server in Germany in about 6 minutes. The iso had been created by ftp download using inumerable resumes on a dialup link. Fairly obviously there was not a lot wrong with this iso, which is what would be expected. This link explains the checksum procedure in depth: http://rsync.samba.org/tech_report/ HTH Bob Parker