Gerhard den Hollander <[EMAIL PROTECTED]> writes:
> see attached amreport.
>
> The avg dump rate is listed as 2M/s
> The avg tape rate is listed as 10M/s
>
> now I've upped maxdumps to 4 (which measn I should expect to get 4 dumps at
> 2 M/s so ~ 8 M/s to holding disk,
> and from there with 10 M/s to tape.
>
> The question is,
> is there any way to speed up the dump process ?
Gerhard,
My first thought was to disable compression, but that's already
done. What's your network technology? 2 MBytes/sec is not the optimum
performance of a quiet 100 Mbit twisted pair ethernet. How fast can
you do repeated ftp transfers of large files from the clients to
/dev/null on the server? This is a good estimate of the maximum
throuput of the network interfaces involved. 100BT maxes out at
approx. 5 MByte/sec. If you do multiple dumps at the same time, things
get worse. Collisions need repeat of data packets and slow things
down. You can get a nice overview via amplot. maxdumps=1 is worth
trying.
On the other hand disk speed might be the bottle neck. I'd run bonnie
on the clients and the server holding disk. I assume you've checked
SCSI settings/errors/DMA for IDE controllers etc. of the holding disk.
Tar might be an alternative sub program for the backups, but I doubt
it's faster.
To me it looks like a classical search for the bottle neck.
HTH,
Johannes Nieß
P.S: As your company can afford that tape drive, it can afford Gigabit
ethernet :-)
P.P.S: What about fully switched 100TP for the clients and a 1000T??
port for the tape server?
