[Discuss] Backing up the entire filesystem

[Dan Ritter]

On Fri, Oct 26, 2018 at 02:30:10PM -0400, Marco Milano wrote:
> 
> 
> On 10/26/18 2:22 PM, Dan Ritter wrote:
> > > > 
> > > > On 10/26/18 1:55 PM, Shirley Márquez Dúlcey wrote:
> > > > > Another thing to keep in mind is that ZFS does have one flaw; it's a
> > > > > memory hog. If you have a large ZFS filesystem you will need a LOT of
> > > > > RAM to get acceptable performance. But it does represent the current
> > > > > state of the art for file system data integrity.
> > > > 
> > > > I think as long as you don't use dedup, it works perfectly fine
> > > > on a system with 8GB or 16GB RAM.
> > 
> > The rule of thumb is 1GB per TB of used space, so for Shirley's
> > NAS boxes, dedup would actually work. I don't recommend it,
> > though.
> > 
> 
> I am configuring a system with 200TB zfs data storage, with only 32GB of RAM,
> ZFS with no dedup, lz4 compression, ubuntu 18.04 server, I am pretty confident
> that it will work perfectly fine.

Yes, the rule of thumb above is the RAM required for dedup, not
anything else.

-dsr-