Copyright (c) Original authors & John Holdsworth 2013-5
Initial version of "mtar", a modified version of the bsdtar sources to multi-thread archive creation. mtar creates archives fully compatable with tar, sometimes dramatically faster.
To enable mutli-threading, add the option "Y" to your tar command e.g.:
$ mtar/bsdtar cfz /tmp/a.tgz emacs-23.3/
real 0m29.664s
user 0m15.712s
sys 0m2.307s
$ mtar/bsdtar cfzY /tmp/a.tgz emacs-23.3/
real 0m15.217s
user 0m20.291s
sys 0m3.285s
You can now control the number of threads used using --option threads=NN after the archive name. The default is the number of processors on the host.
To improve archiving speed two optimisations have been made to the source code. Reading of input files has been multi-threaded for improved performance on slow file systems or when used on network file shares. More importantly compression of the archive created has been multi-threaded by incorporating the "pigz" project for dramatic reductions in archive creation times on modern multi-cored architectures or when using SSDs where disk access is now much faster than single threaded compression.
As compatible as possible binary releases of mtar are available from the following links:
OS X 64 bit built on Snow Leopard (10.6.8)
Linux 32 bit built on Ubuntu (10.04.4)
On OSX you will need to right click on the extracted binary in Finder and click Open initially as it is not developer ID codesigned. On Linux your milage may vary as it no longer seems to be possible to link statically so this version will not run on all Linux variants. Build from the source if you encounter problems.
"mtar" is a modified version of the following software:
bsdtar version 3.1.2 from http://www.libarchive.org/
pigz version 2.3 from http://zlib.net/pigz/
Licensing is as per these original distributions.
To build, clone the repository using the command:
git clone git://github.com/johnno1962/mtar.git
or download the tar ball and extract it then cd into the "mtar" directory and type:
./configure
then, the following will create the binary "./bsdtar":
make
On Linux you will need to manually edit the Makefile to add "-lpthread" to the end of the line containing "LDFLAGS =" and rebuild. You may also need to install zlib using the command:
sudo apt-get install --reinstall zlibc zlib1g zlib1g-dev
This is the initial version of mtar. Please file bug reports to [email protected] or fork and enter pull requests with any improvements on github in the usual way. I should warn you the way pigz_filter.c has been incorporated via a #include from libarchive/archive_write_add_filter_gzip.c is a little untidy to avoid making changes to the project Makefile.
The above copyright notice and this permission notice shall be included in all copies or substantial portions of the Software.
THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.