system response issue

[jd1008]

On 07/13/2015 06:52 PM, g wrote:
> more for thought, is tar building finale file in memory, /tmp, or on 
> the usb3 drive? 
:)
Well, since I was using a pipe, I assume swap backed memory is used.
However, the un-tar process is running in parallel, so the RAM
pipe is shared between the producer "tar" and the consumer
tar, which populates the destination directory with the contents
of the source directory.
That said, I do not think that the entirety of the source dir is first
copied to the "pipe", before it is then consumed by the
"un"tar process. I think the RAM pipe is being read (emptied),
as the producer fills it (using thread synchronization primitives).
Just my guess. I have not looked at tar's source code.