On Sat, 23 Feb 2008, Joerg Schilling wrote: > > Star typically needs 1/4 .. 1/3 of the CPU time needed by GNU tar ans it > uses two processes to do the work in parallel. If you found a case where > star is not faster than GNU tar andwhere the speed is not limited by the > filesystem or the I/O devices, this is a bug that will be fixed if you provide > the needed information to repeat it.
I re-ran my little test today and do see that 'star' does produce somewhat reduced overall run time but does not consume less CPU than GNU tar. This is just a test of the time to archive the files in my home directory. My home directory is in a zfs filesystem. The output is written to a file in the same storage pool but a different filesystem. This time around I used default block sizes rather than 128K. Overall throughput seems on the order of 40MB/second. gtar -cf gtar.tar /home/bfriesen 6.42s user 128.27s system 12% cpu 17:19.66 total -rw-r--r-- 1 bfriesen home 37G Feb 23 10:55 gtar.tar star -c -f star.tar /home/bfriesen 4.11s user 142.65s system 15% cpu 16:03.41 total -rw-r--r-- 1 bfriesen home 37G Feb 23 11:15 star.tar find /home/bfriesen -depth -print 0.55s user 3.52s system 6% cpu 1:01.61 total cpio -o -H ustar -O cpio.tar 11.47s user 122.28s system 11% cpu 18:38.97 total -rwxr-xr-x 1 bfriesen home 37G Feb 23 11:40 cpio.tar* Notice that Sun's cpio marks its output file as executable, which is clearly a bug. Clearly none of these tools are adequate to deal with the massive data storage made easy with zfs storage pools. Zfs requires similarly innovative backup solutions to deal with it. Bob ====================================== Bob Friesenhahn [EMAIL PROTECTED], http://www.simplesystems.org/users/bfriesen/ GraphicsMagick Maintainer, http://www.GraphicsMagick.org/ _______________________________________________ zfs-discuss mailing list zfs-discuss@opensolaris.org http://mail.opensolaris.org/mailman/listinfo/zfs-discuss
