Vzdump speed improvment

Mar 23, 2016
19
3
23
Hi!

I am testing vzdump backup and restore.
I wrote little wrapper script, add pigz parameter "-b 8192".

Normal backup with original pigz:
INFO: status: 100% (652835028992/652835028992), sparse 3% (25770594304), duration 4795, read/write 117/115 MB/s
INFO: transferred 652835 MB in 4795 seconds (136 MB/s)
INFO: archive file size: 396.01GB

Modified pigz (-b 9182)
INFO: status: 100% (652835028992/652835028992), sparse 3% (25774010368), duration 3465, read/write 159/157 MB/s
INFO: transferred 652835 MB in 3465 seconds (188 MB/s)
INFO: archive file size: 396.04GB

Pigz comression method -6 (default) to -4 also significantly speed iprovment, but size minimally differ.


Could you add a parameter to vzdump.conf for the pigz block size?



Also testing restore:
Normal restore zcat-->gzip:
progress 100% (read 652835028992 bytes, duration 7572 sec)
total bytes read 652835028992, sparse bytes 25812570112 (3.95%)

Hacked restore zcat-->pigz:
progress 100% (read 652835028992 bytes, duration 4132 sec)
total bytes read 652835028992, sparse bytes 25812570112 (3.95%)

I think this is a big difference, can you do something without having to change the system (pigz, zcat ..)?

L,