The Search for the Ideal Backup Tool Part 2 of 2

In this installment, we publish our results of comparing ZBackup and Attic backup tools.

We put both ZBackup and Attic to two main tests: Backup and restore.

The input file generally was QEMU’s IMG or QCOW2 format containing CentOS or empty data. The hard disk was all SSD RAID1+0. The CPU was 2xHaswell Xeon 2.3 GHz with 6 cores each.

Backup Test

Attic

Backup Number input Size (GB) Num Files Time (hh:mm:ss) Size of folder (GB) Effective Compression Ratio Notes
1 50 3 00:09:54 2.1 23.81
2 50 3 00:00:18 2.1 23.81 No new files. No updates
3 50 3 00:01:15 2.1 23.81 No new files. But minor update to one of the larger files
4 470 5 00:50:16 2.16 217.59 2 new files
5 470 5 00:41:31 2.16 217.59 No new files. But minor update to one of the larger files
Total data processed = 1,090 GB.
Total time for data  = 6,194 seconds

Attic takes 5.68 seconds per GB for data that is generally duplicate like IMG/QCOW2 files containing CentOS install.

 

ZBackup

Backup Number input Size (GB) Num Files Time (hh:mm:ss) Size of folder (GB) Effective Compression Ratio Notes
1 50 3 00:45:43 1.6 31.25
2 50 3 00:08:17 1.6 31.25 No new files. No updates
3 50 3 00:08:22 1.6 31.25 No new files. But minor update to one of the larger files
4 470 5 04:10:13 1.6 293.75 2 new files
5 470 5 04:08:00 1.6 293.75 No new files. But minor update to one of the larger files
Total data processed = 1,090 GB.
Total time for data  = 33,635 seconds

ZBackup takes 30.86 seconds per GB for data that is generally duplicate like IMG/QCOW2 files containing CentOS install.

Restore Test

For restore, all the restored file must match the SHA1 fingerprint as the original file exactly. Both ZBackup and Attic passed this test.

Attic

Restore Number Restore Size (GB) Num files Time (hh:mm:ss)
1 350 1 00:39:11
2 25 1 00:00:20
3 48 2 00:05:18
Total data processed = 423 GB.
Total time for data  = 2,689 seconds

 

Attic takes 6.35 seconds per GB to restore data.

ZBackup

Restore Number Restore Size (GB) Num files Time (hh:mm:ss)
1 350 1 00:24:29 (2 GB cache)
2 350 1 00:26:40 (40 MB cache)
3 25 1 00:01:19
4 48 2 00:06:02
Total data processed = 773 GB.
Total time for data  = 3,510 seconds

 

ZBackup takes 4.54 seconds per GB to restore data.

Comparison

Attic Zbackup Attic vs Zbackup
Backup -seconds/GB 5.68 30.86 -443.31%
Backup Compression 217 293 35.02%
Restore-seconds/GB 6.35 4.54 -28.50%

 

Final selection depends on which factor has more weight. For instance, if you have a cheaper cost to store a GB but need  fast backup time, Attic seems best. If you care about size, Zbackup seems best at the expense of time. I believe, ZBackup has selectable compression algorithms so it might even be faster if you choose a faster LZO compressor, however the author mentions LZO is a caveat. Our quick tests show LZO is definitely faster but compression ratio is lower than attic.

Do let us know you thoughts in the comments

Post Script – The Test script Files
Attic Create Backup Script
run=$1
if [ "$run" == "" ]; then
 echo "Error run number is required."
 exit
fi
 
attic create --stats /vm_backup/atticrepo.attic::$run /virtual_machines/images/file1.img /virtual_machines/images/file2.img . . .
du -h -d 1 /vm_backup/atticrepo.attic
echo "Done"
ZBackup CREATE BACKUP SCRIPT
. . . Preamble Same as attic . . .
zbackup backup --non-encrypted --threads 8 --cache-size 1024mb
/vm_backup/zbak/backups/file1.img.$run < /virtual_machines/images/file1.img

. . . other files . . .

sha1sum was used to calculate SHA1 on restored files.