This is the mail archive of the cygwin mailing list for the Cygwin project.


Index Nav: [Date Index] [Subject Index] [Author Index] [Thread Index]
Message Nav: [Date Prev] [Date Next] [Thread Prev] [Thread Next]
Other format: [Raw text]

Re: Telnet / SSH connection timeout on LAN


Greetings, Warren Young!

>>> Consider all the disk I/O required.  In its default mode, rsync must do a
>>> full directory tree scan on the directory to be transferred, on *both* ends.
>>> For each file with a different mtime or size, it must then recompute all the
>>> hashes in that file, again on both sides.
>> 
>> Wrong. In default mode, rsync only care about timestamp and size.
>> It will not go on hashing crusade unless explicitly told to.

> You misunderstood what I wrote.  Given a changed mtime or file size, rsync
> then must re-read the file on both sides in order to generate a series of
> checksums on chunks of the file in order to determine which parts of the
> file have changed, so that it transfers only the changes.  See:

>  
> https://en.wikipedia.org/wiki/Rsync#Determining_which_parts_of_a_file_have_changed

> If you skip this step, you must transfer the entire file contents to the
> other side, since a difference only in the mtime and/or file size doesnât
> tell you which parts of the file have changed.

In my environment, a small touch to the original file cause changes throughout
the entirety of its stored image. ('cause storage format is actually an
archive, and a small change here and there in the source file cause massive
shifts in the resulting image.)
You see, it is a matter of application and environment.


-- 
With best regards,
Andrey Repin
Monday, July 13, 2015 19:31:58

Sorry for my terrible english...

Index Nav: [Date Index] [Subject Index] [Author Index] [Thread Index]
Message Nav: [Date Prev] [Date Next] [Thread Prev] [Thread Next]