Timothy J Massey wrote at about 22:46:39 -0400 on Tuesday, April 12, 2011:

 > Timothy J Massey <tmassey AT obscorp DOT com> wrote on 04/12/2011 10:13:11 PM:
 >
 > > But give it a try first:  unless that production server is a 600MHz
 > > machine with 512MB RAM and a single SATA spindle, you will most
 > > likely be fine (and if you *are* running like that, well, you have
 > > other problems!  :) ).  (Actually, I have one client with servers
 > > that are dual-processor 600MHz with 1GB RAM that I back up during
 > > the day and the users at this location almost *never* notice.)
 >
 > To clarify and expand this:  they are IBM Netfinity 5600 servers.  2 x
 > 600MHz Intel P3 processors, 1GB RAM, and 6 x 18GB SCSI-160 10,000 RPM
 > drives in a RAID 5 array with an IBM ServeRAID hardware RAID controller.
 > The systems are old and (processor) slow, but the disk performance is
 > really pretty good, even today:  it'll easily saturate GigE.
 >

 > My point for this:  CPU power matters little on the client side.  RAM
 > matters, but only once you have enough:  depending on the number of files,
 > the amount of RAM you truly need is literally in the hundreds of
 > megabytes.  What *really* matters is I/O and network throughput--and on
 > any halfway-decent server with multiple high-RPM hard drives, you will be
 > limited by network bandwidth more than anything else.

As I have mentioned before, I have succeeded with just 64MB of RAM of
which only about 20MB is free. I do have swap, but it really doesn't
use much swap. Now I am just backing up "normal" Linux and Windows
worstations and laptops where each backup has maybe a couple of
hundred thousand files and 20-50GB... but it does work... I use the
rsync/rsyncd transfer method and rsync >~ 3.0 is pretty memory efficient as
long as you have a "normal" filesystem without "humongous" numbers of
hard links or "insanely" large numbers of files per directory.
On small systems, I still find the primary limitations are bandwidth
(I backup many machines over 802.11g wireless) and cpu power for
compression (when I use a 500MHz Arm processor).

------------------------------------------------------------------------------
Forrester Wave Report - Recovery time is now measured in hours and minutes
not days. Key insights are discussed in the 2010 Forrester Wave Report as
part of an in-depth evaluation of disaster recovery service providers.
Forrester found the best-in-class provider in terms of services and vision.
Read this report now!  http://p.sf.net/sfu/ibm-webcastpromo
_______________________________________________
BackupPC-users mailing list
BackupPC-users AT lists.sourceforge DOT net
List:    https://lists.sourceforge.net/lists/listinfo/backuppc-users
Wiki:    http://backuppc.wiki.sourceforge.net
Project: http://backuppc.sourceforge.net/