Re: Backups seem to take too long(scsi tape)
On: Wed, 4 Nov 1998 12:29:57 -0500 (EST) servis writes:
>
> Hi all,
> I have a Seagate Tapestore 8G on a scsi-2 controller. When I back
> up my drives(ext2, vfat) and some smbfs mounted drives(over a 10-T)
> it seems to take too long. I am just using tar whith compression.
> Here are the stats from tar:
>
> Total bytes written: 5752760320 (5.8 Gb) (contained in 130541
> files/dir) Elapsed time: 05:14:882, 18882 sec Throughput per second:
> 298Kb/sec
>
> Is this expected? The tape says that it should get between
> 600Kb/sec and 1000Kb/sec depending on compression ratio.
>
> What can I do to speed this up?
Use tar without compression and let your tape use its hardware
compression. Software compression is usually quite slow,[1] on my
computer slower than the tape speed.
Torsten
BTW: With hardware compression enabled I get about 700 KB/s with a
DDS2-DAT tape on a DDS1 tape (2GB uncompressed capacity).
Footnotes:
[1] about 500 KB/s using gzip -9 on a Pentium 133 CPU.
Reply to: