Linked by Joel Dahl on Sun 25th Apr 2010 19:25 UTC
FreeBSD Today Jeff Roberson committed his patches to FreeBSD 9 for adding journaling to UFS. No more background fsck after unclean shutdowns! This is a major landmark in the history of UFS, with 11000 new lines of code (and about 2000 removed). Much of the work was done in collaboration with Kirk McKusick, the original author of FFS and Softupdates, under sponsorship form Yahoo!, Juniper and iXsystems. Jeff's blog contains quite a lot of technical information of his work. There's also information on the FreeBSD mailing lists.
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Why isnt Hammer in FreeBSD??
by circlomanen on Mon 26th Apr 2010 05:45 UTC
circlomanen
Member since:
2008-11-02

I cant understand why FreeBSD doesnt use Hammer instead of USF or ZFS? Hammer is BSD licens and more suitable for desktop use.

Reply Score: 0

RE: Why isnt Hammer in FreeBSD??
by Lazarus on Mon 26th Apr 2010 06:44 in reply to "Why isnt Hammer in FreeBSD??"
Lazarus Member since:
2005-08-10

Hammer is also relatively new, and therefore has has much less testing than more mature filesystems for starters.

Furthermore Hammer as it is in DragonFly relies on a ton of changes made over years to the VFS layer alone and likely changes to many other kernel subsystems that have not occurred in FreeBSD as they were not needed by it and would thus need to be ported before any serious attempt to get Hammer working could get underway.

And before you mention the fuse ports of Hammer that exist for Linux and Mac OS X, realize that they are to allow read-only access to Hammer filesystems and are a few versions behind at any rate.

Reply Parent Score: 2

gnemmi Member since:
2006-08-17

Hammer is also relatively new, and therefore has has much less testing than more mature filesystems for starters.


Hammer is in version 4 already and has been heavily commited ever since day 1.

ZFS is still one of the topics that causes the bulk of emails sent to @stable and @questions ...

Furthermore Hammer as it is in DragonFly relies on a ton of changes made over years to the VFS layer alone and likely changes to many other kernel subsystems that have not occurred in FreeBSD as they were not needed by it and would thus need to be ported before any serious attempt to get Hammer working could get underway.


Are you sure about that?
Try asking in hammer-request at lists.dragonflybsd.org .. People interested in porting HAMMER to other operating systems should contact Matthew Dillon at dillon at backplane.com

And before you mention the fuse ports of Hammer that exist for Linux and Mac OS X, realize that they are to allow read-only access to Hammer filesystems and are a few versions behind at any rate.


Even if it is opensource, Linux still has problems working with UFS .. I wouldn't count on Linux being the one to take Hammerfs outside of DragonFlyBSD's world..

Edited 2010-04-26 07:06 UTC

Reply Parent Score: 1

RE: Why isnt Hammer in FreeBSD??
by gnemmi on Mon 26th Apr 2010 06:45 in reply to "Why isnt Hammer in FreeBSD??"
gnemmi Member since:
2006-08-17

Maybe because they are strongly reluctant to import the coding marvel of the very same guy they had kicked out?

Maybe because the code doesn't have a "FreeBSD feel to it" .. like in Murenin's port of the OpenBSD sensors framework to FreeBSD (GSoC2007/cnst-sensors)?

Maybe because they decided that with all the money, devel time and debugging effort they spent porting ZFS, ZFS should be the FS you should use regardless of wether it is or it is not a better FS than Hammer?

Maybe because of the same reasons why the keep Sendmail in base instead of moving it to ports and import DMA or OpenSMTPD to base (which are _nothing_ but historical reasons)?

Go ask FreeBSD satus quo ... they probably have a rock solid and scientific explanations about it like "Because it has been there from the beginning" or something lines along that way ..

Anyways, my congrats and sincere thanks to Jeff for his work. It will be highly aprecciated in my ZFS free world ;)

Edited 2010-04-26 07:04 UTC

Reply Parent Score: 0

circlomanen Member since:
2008-11-02

Furthermore Hammer as it is in DragonFly relies on a ton of changes made over years to the VFS layer alone and likely changes to many other kernel subsystems that have not occurred in FreeBSD as they were not needed by it and would thus need to be ported before any serious attempt to get Hammer working could get underway.



That is a good reason! ;)
I didnt think of that, this early in the morning here in sweden. I was just thinking BSD = BSD.

Reply Parent Score: 1

RE: Why isnt Hammer in FreeBSD??
by bsdimp on Tue 27th Apr 2010 02:53 in reply to "Why isnt Hammer in FreeBSD??"
bsdimp Member since:
2007-02-23

HAMMER isn't in FreeBSD because nobody had ported the code to FreeBSD. In addition, there's concerns about scalability and reliability of the code, and how well it will fit into FreeBSD's model for multitasking. It is a big project, and it isn't clear there'd be a big win from completing it. there was also a lot of hype when it came out that turned out to be overblown when people took a first look at it, which has lead to a reluctance to give it another look.

So until somebody shows up with a port of HAMMER, it is silly to talk about "why" it isn't in FreeBSD. FreeBSD has evolved significantly in one direction, to support better MP scaling, and DFBSD has evolved in other directions. This means the porting effort would be large. Much like porting between Linux 2.0 and 2.6 in many respects, to draw an analogy.

Warner

Reply Parent Score: 2