Lifetime of FreeBSD branches

Scott Long scottl at
Tue May 24 12:15:39 PDT 2005

Mike Jakubik wrote:

> Could someone point me to a resource that outlines the expected supported
> lifetime of all the branches? Can't find anything concrete on the webpage.
> I'm developing a product, which i hope will run on FreeBSD. However the
> rapid development of 5, and now 6 arriving out in a few months has me
> worried if FreeBSD will be the right choice short and long term. I have
> even considered using 4.11 for its stability and speed on single processor
> systems, but I'm worried that some ports/hw will not be supported.
> The recent amount of problems with 5 has me a little discouraged too, and
> even considering Linux as an alternative. Hopefully that wont be the case,
> but a clear outline of whats to come would be very helpful in the decision
> making.
> Thanks.

First of all, as the release engineer, I cannot stress enough that 6.0
is only an evolutionary step from 5.x.  It's natural to assume that
every major version change indicates major (and majorly destabilizing)
changes, but that is exactly what we are trying to get away from now.
When people ask what the future of 5.x is, my answer is "6.x" because
that's exactly what it is: a continuation and refinement of what we
did with 5.x, with a few needed architecture changes and features.

We are going to release 6.0 within the next few months, and 6.1 4
months after that.  There will be a 5.5 release inbetween there just
to wrap up that branch and provide users a bridge for 6.x.  I don't
expect there to be any 5.x releases after 5.5 because there simply
won't be anything left to offer in that branch that isn't in 6.x.

The 6.x transition will not have the handicaps that the 5.x transition
had for users.  It does not have a significantly different compiler
that requires major porting work for user applications.  It does not
have a dozen new experimental features that are still being debugged.
The only really new and experimental feature is the SMP VFS work, but
that has been undergoing a significant amount of testing, and it can
be turned off if need be.  This is in sharp contrast to 5.x that had
so many overlapping experimental areas that it was hard to test, isolate
and fix problems.

I think that we've gotten over most of the stability and performance
hurdles of 5.x.  We have a complete OS, not just a kernel, and it has
more components than the 4.x OS.  But despite that, most bugs reported
on this list seem to get solved fairly quickly, either with advice from
others or with a commit to the source tree.  We have a number of very
strong and very active ports and source tree committers that are doing a
very good job of refining the system, and I expect that to continue.
More bug reports are always welcome, and if you feel that there is a bug
that isn't getting attention that is critical for 6.0, email
re at about it, or email me personally.

As for performance, Kris has shown that the 5.x/6.x performance penalty
is now much more of a myth than reality. SMP on 6.x is significantly
more scalable and high performance than anything we've released before.
We are finally starting to see the benefits of our SMPng design.  Most
of the infrastructure work is done, so 6.x will be about refining it,
locking down more peripheral drivers and components, and tending to the
general details that have fallen behind in 5.x.  It's going to be a very
good release series.

I understand that there are some specific reasons for some people to
stick with 4.x.  There were people that stuck with 2.2.x back during
the 3.x and 4.x days because they also had specific needs.  I think
that this is fine if done for the right reasons, and I'm glad that those
people are willing to stick with FreeBSD instead of looking elsewhere.
However, if there is anything that we can do to help with the transition
forward to 5.x/6.x, please let me know.

Again, please don't take the abrupt switch to 6.0 to mean that 5.x is
flawed or that 6.x will also have a short lifespan.  The real purpose
of the switch is nothing but positive; it'll keep us focused and prevent
us from overreaching and overextending ourselves.  It's a very good
and very postive strategy.


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