Re: [BackupPC-users] Curious

[Guillaume F. <gf...@lo...>]

"Mark D. Mongtomery II" <tec...@te...> wrote:
> I've been pondering some things as I browse the list and work on the
machine I've been configuring and was wondering if anyone had some insight
for me and any others who may be pondering the same things.

I've been using BackupPC for a bit more than two years now with good
success, so here are some toughts.

> 1.  How much does the CPU speed affect the BackupPC process?
> I know that a better CPU would allow more jobs to run simultaneously, but
how much does the speed really affect each job?

I think that the only real CPU constrain is to be able to compress with gzip
fast enough. The other tasks should not too be CPU intensive.

> 2.  How does network speed affect the process?  Obviously, a faster
network would allow the files to transfer faster, but they still have to be
processed and compressed.

I think that it's the most important part of the system speedwise.

> 3.  Assuming a standard 100Mbit lan, would a 1Gb NIC in the BackupPC box
make any difference when doing multiple simultaneous backup jobs?  My logic
tells me only if there was actually a Gigabit port on the switch that the
BackupPC box was plugged into.  But, as always, I may be wrong.

Of course, the gigabit NIC on the PC will work at gigabit speed only if it's
connected to a gigabit port on the switch. If you connect a gigabit NIC to a
100 Mbps port, you'll get 0 speed gain compared to a 100 Mbps NIC. If you
have a fast enough PC, a gigabit NIC (and switch) should make an
improvement.

> 4.  Assuming a pure IDE system, with the backuppc disk separate from the
system disk, how much does hard disk speed affect the BackupPC process?
> We currently have an older 20GB as the primary system disk, and then a
nice new ATA133 80GB disk on the second channel as the backuppc disk.
> The main issue is that the machine is a Cyrix MII 333 (250Mhz) so the
disks are most likely running ATA33 or ATA66 (I haven't checked).
> I'm trying to figure out if putting in an ATA controller to run the
BackupPC disk (and also the disk we want to backup the backup onto
eventually) would make any performance difference.

As far as I know, the disk only has to be as fast as the network. So you
shouldn't have problems with an ATA33 disk on a 100 Mbps network if your PC
has enough RAM to avoid swaping. On a gigabit network, you'll need at least
ATA66 with DMA and no swap. However, a 233 MHz CPU is quite slow; I'm not
even sure if it can compress traffic at 100 Mbps. If I were you, I would
rather buy another motherboard/CPU than a ATA controller.

The specs really depend on how much hosts that you want to backup. I'm
backuping 10 hosts on a 10 Mbps network with a PC similar to yours. It works
well, but it's a bit slow; if I had to backup more than 15-20 PCs, I would
consider buying a bigger PC.

Hope this helps a bit,
GFK's
-- 
Guillaume Filion, ing. jr
Logidac Tech., Beaumont, Québec, Canada - http://logidac.com/
PGP Key and more: http://guillaume.filion.org/