[ale] UFS/SDS v VxFS/VxVM (was: ext3 v reiserfs)

[Dylan Northrup]

A long time ago, (14.09.03), in a galaxy far, far away, matty91 at bellsouth.n...:

:=On Sun, 14 Sep 2003, Greg wrote:
:=
:=> Since you can strip the logs out of ext3 and get ext files, which can be
:=> exported to other OS's which have no ext3/reiserfs support, that could be a
:=> compelling reason to use ext3 - the ability to go to a more universally
:=> acceptable format.  However I think that only the BSD's are this way, as
:=> they use SoftUpdates to the ffs to solve the problems that logging are
:=> supposed to handle.  Don't know about Solaris.
:=
:=Solaris incorporates UFS logging into their UFS implementation. For large
:=file systems, I would recommend deploying VxFS.

Depends on what your system requirements are.  The coupling of VxFS and VxVM
gives you some advantages and power you don't necessarily get when you
combine UFS and SDS (Sun's Volume Manager).  Performance-wise I have yet to
run into a situation where UFS was slower than VxFS.  If you set up logging
with UFS you match the "dirty startup" times of VxFS.  The one clear cut
advantage VxFS has (that I've made use of) is it's ability to shrink
volumes. . . but to be honest, I've grown volumes 100 times more frequently
than I've shrunk them.  And having volumes that are too small is a sign of
poor planning in the first case (whether it's on the part of the technical
staff or on the part of the folks who provided requirements to the technical
staff).

For volume management (which should play a big role in what file system you
select under Solaris) I find SDS to be more straightforward than VxVM.  I
don't need to do two reboots to mirror my root disks (install VxVM/VxFS, 
reboot, encapsulate root disk, reboot, begin mirroring).  I am using a
native FS on the host so I don't need any specific kernel modules just so I
can boot up.  I don't need to uninstall VxFS/VxVM when upgrading a system.
And, for my personal use, Solaris 9 has SDS integrated into the OS so it's
free and I don't need to pay for a node-locked license for the Vx stuff that
I can't transfer to a new box without bothering with the hassle of 
contacting Veritas if/when I want to upgrade my iron.

-- 
Dylan Northrup <*> docx at io.com <*> http://www.io.com/~docx/
"Harder to work, harder to strive, hard to be glad to be alive, but it's 
 really worth it if you give it a try." -- Cowboy Mouth, 'Easy'