Bandwidth Limits

tim.conway at tim.conway at
Wed Nov 21 01:49:59 EST 2001

That was just too small a test.  --bwlimit= causes rsync to sleep for an 
appropriate interval after each data block (not tcp packet), in order to 
pull the average transfer rate down to the specified limit.  Your reported 
transfer rate was only a little above 1kbps anyway, as the test was so 
small, there wasn't time to even get the send>sleep>send>sleep cycle 
going... overhead stretched the time out so much that the 128k transferred 
took an insignificant portion of the total runtime.  Try a larger test. 
maybe a meg or so.  averages are meaningless on single instances... 
average height of an adult american male is about 6 feet, right?  if you 
find a man 4 feet tall, that doesn't mean the average is wrong.

Tim Conway
tim.conway at
Philips Semiconductor - Longmont TC
1880 Industrial Circle, Suite D
Longmont, CO 80501
Available via SameTime Connect within Philips, n9hmg on AIM
perl -e 'print pack(nnnnnnnnnnnn, 
".\n" '
"There are some who call me.... Tim?"

uid0 at
Sent by: rsync-admin at
11/19/2001 06:04 PM

        To:     Tim Conway/LMT/SC/PHILIPS at AMEC
        cc:     rsync at
        Subject:        Re: Bandwidth Limits

On Mon, 2001-11-19 at 17:45:26 -0700, tim.conway at wrote...

; Try this commandline:
; rsync -avz -e ssh --bwlimit=64 localfiles.tar.gz 
; user at remote:/path/to/file/arch

I did. This is what I get....I created a 128K file..

bash-2.05$ rsync --stats -avz --bwlimit=8 -e ssh blah:~/out .
user at remote's password:
receiving file list ... done

Number of files: 1
Number of files transferred: 1
Total file size: 127976 bytes
Total transferred file size: 127976 bytes
Literal data: 127976 bytes
Matched data: 0 bytes
File list size: 57
Total bytes written: 32
Total bytes read: 15325

wrote 32 bytes  read 15325 bytes  1228.56 bytes/sec
total size is 127976  speedup is 8.33
bash-2.05$ ls -l out
-rw-------  1 user  luser  127976 Nov 19 19:01 out

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