Performance between tar and vxrestore

[Xentar]

Hi All,

Recently we did try to migrate the data from a mount point /A with around 90G data to other mount point /B, and the result as the following:

Use tar command:
cd /A; tar cfpE - . | (cd /B; tar xfpE -), it completes around 1 hr

Use vxdump and vxrestore aommnd:
cd /; vxdump 0f - /A | (cd /B; vxrestore -yxf -), it takes about 48 hrs to compelete.

I would like to know is the result normal? as the performance between tar and vxrestore is quite large.
Or any parameter we can use in order to shortern the time?

Regards,
Xentar

[Marianne]

tar will only backup and restore actual data. vxdump/restore will do a dump and restore of the entire filesystem, regardless of amount of data. What is the total filesystem size?
I'd expect vxdump to take longer, but not 48 times longer...
Which O/S? VxFS version?
Any reason your not migrating using volume mirroring?

[LUCS]

Perhaps there is an  IO bottleneck with the underlying storage system?

You might try timeing a vxdump  to file or tape and then restoring from that.

The 'sar' system activity recorder, if you have it set up, would be a good way
of analyzing your two data copy methods.