On Fri, Jan 21, 2005 at 11:30:02AM -0500, Brian Cuttler wrote:
> Amanda 2.4.2p2
> Solaris 8
> SDLT 220
> 
> We recently make a couple of changes to our amanda conf (well, one
> of our amanda server configs).
> 
> 1) changed the config name
> 2) changed from SW to HW compression, increased tape length
...
> 
> We are seeing that amanda used to perform level 0 and 1 dumps (DUMP
> type dumps) and we are now seeing that we are getting to level 2
> dumps. We where currious as to why.
> 
...
> 
> It looks like there are a couple of things in play here.
> 
> 1) From amanda.conf
> bumpsize  50 MB         # minimum savings (threshold) to bump level 1 -> 2
> bumpdays     1          # minimum days at each level
> bumpmult     2          # threshold = bumpsize * (level-1)**bumpmult
> 

Just guessing.  Much of amanda's planing is based on how much data
is "taped", not how much is backed up.  I'm thinking of the balancing
act it performs.

Since you switched from SW to HW compression, the amount of data that
is being "taped" is larger.  Thus you may be hitting our bump figures
if they are calculated on the taped data and not the original data.

-- 
Jon H. LaBadie                  jon AT jgcomp DOT com
 JG Computing
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 Princeton, NJ  08540-4322      (609) 683-7220 (fax)