"xargs tar cf backup.tar < $manifest" recreates the tar file with each
"batch" execed by xargs. In general this results in only a fraction of
the desired files being backed up.
Without the proposed fix for deletion performance [1], this test is
probably unreasonably slow compared to others at the same
small/medium/large scale.
[1]: id:20210414021627.1236560-3-david@tethera.net
I couldn't run the performance tests on my machines due to a hardcoded
bash path. Use env for finding bash in weird systems like NixOS.
Signed-off-by: William Casarin <jb55@jb55.com>
Several people have observed that this is surprisingly slow, and we
have a proposal to add tagging into this code path, so we want to make
sure it doesn't imply too much of a performance hit.
The files (test) scripts source (with builtin command `.`) provides
information which the scripts depend, and without the `source` to
succeed allowing script to continue may lead to dangerous situations
(e.g. rm -rf "${undefined_variable}"/*).
At the end of all source (.) lines construct ' || exit 1' was added;
In our case the script script will exit if it cannot find (or read) the
file to be sourced. Additionally script would also exits if the last
command of the sourced file exited nonzero.
