Louwtjie Burger <[EMAIL PROTECTED]> wrote:
> Server: T5120 on 10 U5
> Storage: Internal 8 drives on SAS HW RAID (R5)
> Oracle: ZFS fs, recordsize=8K and atime=off
> Tape: LTO-4 (half height) on SAS interface.
>
> Dumping a large file from memory using tar to LTO yields 44 MB/s ... I
> suspect the CPU cannot push more since it's a single thread doing all the
> work.
What is the speed of the LTO?
If you are talking about "tar", it is unclea which TAR implementation you are
referring to. Sun tar is not very fast. GNU tar is not very fast. Star is
optimized for best speed.
I recommend to check star. The standard blocksize of tar (10 kB) is not optimal
for tape drives. If you like to get speed and best portability of the tapes,
use
a block size of 63 kB and if you like to get best speed, use 256 kB as
blocksize.
I recommend to use:
star -c -time bs=256k f=/dev/rmt/.... files...
Star should be able to give you the native LTO speed.
Jörg
--
EMail:[EMAIL PROTECTED] (home) Jörg Schilling D-13353 Berlin
[EMAIL PROTECTED] (uni)
[EMAIL PROTECTED] (work) Blog: http://schily.blogspot.com/
URL: http://cdrecord.berlios.de/private/ ftp://ftp.berlios.de/pub/schily
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