All-
I'm preparing to re-install (not update) my personal workstation (which
should have been named `guinea-pig') with Digital Unix 4.0, before we
put 4.0 on any other more important machines. In most respects I know
exactly what I want to do and how to do it, but despite the fact that
we've been using the advanced filesystem here for nearly a year I still
have some fundamental/bonehead questions about it.
I spent quite a bit of time going through the archives for this list
(and found a lot of useful information about the AdvFS) without finding
the answers to my questions. If I haven't RTFM'ed enough please let me
know which FM I should read. Pointers to a good (detailed) reference on
the AdvFS would be especially appreciated. Chapter 8 of the 3.x System
Administration book (AA-PS2RC-TE) doesn't go into any of the types of
details I'm interested in.
1) I've seen the term `metadata' mentioned a hundred times on this list
but I have yet to find a clear definition of what exactly the metadata is.
>From the context it seems to be akin to dynamically allocated groups of
inodes, but I suspect there's more to it than that (or that it's
something completely different). The AFA320 release notes
(/usr/advfs/AFA320_RELNOTES.*) seem to support my hypothesis without
actually spelling it out.
2) If I were creating a UFS filesystem, I could control the inode density
and the minfree with `newfs'. If the metadata is along the lines of
dynamically allocated inodes I obviously don't need to worry about
increasing the density of inodes, but is there a way to create a
filesystem that defaults to having fewer inodes? For the UFS you can
buy yourself some additional space if you know you're not going to need
the inodes; can (should?) this be done with AdvFS? I see the otherwise
undocumented `-x' option to mkfdmn & addvol mentioned in the AFA320
release notes. It appears that the default extent allocation policy is
`as low as it goes'. Is this correct?
UFS has a concept of `minfree'. Is there anything similar in the AdvFS?
If there is a minfree, can I adjust it a la newfs/tunefs? I'm guessing
there's no need for a `minfree' for AdvFS because of different block
allocation algorithms than UFS. Am I correct?
3) Is there any reason to *not* change the value for RPM to match my drives
when repartitioning my drives with disklabel? Both of my drives spin at
5400 RPM. Will it do any harm (or any good) to up the RPM entry from the
default of 3600? This obviously has nothing to do with AdvFS but it's also
something I've been thinking about changing when I re-install.
I will of course summarize.
Tim
--
Tim Mooney mooney_at_toons.cc.ndsu.NoDak.edu
Information Technology Services (701) 231-1076 (Voice)
Room 242-J6, IACC Bldg. (701) 231-8541 (FAX)
North Dakota State University, Fargo, ND 58105
Received on Tue Jul 02 1996 - 06:13:20 NZST