Re: WAPBL vs. lfs?

[Thor Lancelot Simon <tls%rek.tjls.com@localhost>]

On Fri, Aug 22, 2008 at 10:08:17PM +0200, Geert Hendrickx wrote:
> Hi,
> 
> from a user point of view, what advantages does lfs still offer over ffs
> now that we have WAPBL?

LFS doesn't work in -current so it's basically a moot point.  Unless someone
steps up to adapt it to all the SMP changes in the kernel since 4.0 it may
never really work again.

However, LFS in 4.x can use between 75% and 100% of the disk bandwidth for
writes whether those are small file writes, directory creates, removes,
you name it.  Try the same thing with WAPBL and you'll see that though it
is a lot faster than standard FFS, it's still able to use well under half
the maximum throughput of the disk in many such cases -- and that is even
if you don't subtract the extra-writes penalty for the journal (all
metadata is effectively written twice).

-- 
Thor Lancelot Simon                                        
tls%rek.tjls.com@localhost
 "My guess is that the minimal training typically provided would only
 have given the party in question multiple new and elaborate ways to do
 something incomprehensibly stupid and dangerous."      -Rich Goldstone