Did you ever want to know how fast your tar is or how
much data it has transferred already. How about using
socket or nc to copy files either with or
without compression over a fast network connection, which one is
faster?
If you want to know the answer, use cpipe as a totally
unscientific approach to measure throughput.
Cpipe copies its standard input to its standard output
while measuring the time it takes to read an input buffer and write an
output buffer. Statistics of average throughput and the total amount
of bytes copied are printed to the standard error output.
The command
tar cCf / - usr | cpipe -vr -vw -vt > /dev/null
results in an output like
... in: 19.541ms at 6.4MB/s ( 4.7MB/s avg) 2.0MB out: 0.004ms at 30.5GB/s ( 27.1GB/s avg) 2.0MB thru: 19.865ms at 6.3MB/s ( 4.6MB/s avg) 2.0MB ...
The first column shows the times it takes to handle one buffer of data (128kB by default). The read-call took 19.541ms, the write-call to /dev/null took just 0.004ms and from the start of the read to the end of write, it took 19.865ms.
The second column shows the result of dividing the buffer size (128kB by default) by the times in the first column.
The current version is 3.0.2. You may want to read the
list of recent CHANGES. The software
can be downloaded from