I get a good 8 hours of sleep.  As I get older I find myself unable to

    pull all-nighters any more without really screwing up the entire next

    day.
    --
    ZFS serves a different purpose and I think it is cool, but as time

    has progressed I find myself liking ZFS's design methodology less and

    less, and I am very glad I decided against trying to port it.  I do

    not think it is a good idea to put all one's marbles in a single copy

    of a filesystem, no matter how redundant its storage model is, and there

    isn't much point having that level of redundancy if the intent is

    to operate in a replicated environment.
    The problem ZFS has is that it is TOO redundant.  You just don't need

    that scale of redundancy if you intend to operate in a multi-master

    replicated environment because you not only have wholely independant

    (logical) copies of the filesystem, they can also all be live and online

    at the same time.
    HAMMER's approach to redundancy is logical replication of the entire

    filesystem.  That is, wholely independant copies operating on different

    machines in different locations.
    Ultimately HAMMER's mirroring features will be used to further our

    clustering goals.  The major goal of this project is transparent

    clustering and a major requirement for that is to have a multi-master

    replicated environment.  That is the role HAMMER will eventually fill.

    We wont have multi-master in 2.0, but there's a good chance we will

    have it by the end of next year.
						-Matt

As *I* have gotten older 'day' has become virtualized anyway. Partly 'coz I

spend half the year on Washington DC's timezone and half on Hong Kong's

timezone and work nights anyway 'coz that's when the cable modems are at their 
Dunno about Slowlaris, but from what is passing by on 7-CURRENT, despite Pawel's

excellent work, it 'seems to me' that ZFS is more fragile at the OS & RAM

resource level than even yesteryear's storage media was/is at the hardware level.
I can't put a lot of faith in a fs that knocks the whole box offline ev'ry now 
Basically, I'm a believer in getting any layer between hardware and

'logical-whatever' as simple and robust as can be.
ZFS seem to me to have put too much in the way of DB features into the fs.
HAMMER - at first glance - seems to have a simpler and more elegant approach to

the 'basics'.
Just enough of the 'DB' in it (as all fs are in one way or another)

to provide the flexibility, scaleability, and resilience, not so much as to

negate its advantages with fragile, complex structures.
						-Matt
Given the recent trend toward more affordable SAN hardware and links, it should

find a niche at about the right time.
Perhaps even the 'killer app' (along with kernel virtualization) that DragonFly

could use..
It has had me take it off the back-burner again, anyway... off to dld an new iso..
Best,
Bill

Mind you, ZFS is marked as an experimental feature in FreeBSD and even

that, it is already used by many in production. The bug you are refering

to, is just a bug, and I believe it's already fixed, this is not like a

design flaw in ZFS, so your comment is simply unfair.
It took many years to design and many years to implement ZFS, and

believe me, it's not an easy task to create such advance piece of

software. I wish Matt the best, but I'm quite sceptical.
PS. I think Sun with his great work on Solaris is worth at least a bit

of respect by getting the "Solaris" spelling right.
--=20

Pawel Jakub Dawidek                       http://www.wheel.pl

pjd@FreeBSD.org                           http://www.FreeBSD.org

FreeBSD committer                         Am I Evil? Yes, I Am!