5.x concerns

[Chris]

Hi

I switched over half a dozen or so servers to 5.x since october last
year expecting the same stability and performance I have had from
freebsd 4.x, after running it for 2 or 3 months I have ran into some
problems/concerns, listed below.  This is not intended for anything
other then feedback and andswers to my questions I am well aware of
the hard work put into freebsd and will continue to love the os.

1 - Speed, performance, All but 2 of the servers are normal Single
processor machines and I think mainstream is still single processor,
whilst there are smp machines and 64bit machines cropping up they are
still a minority, what I have noticed first hand and read on the web
is that 5.3 is sluggish behind 4.10 on single cpu machines, whilst on
64bit and smp machines it whizzes along.  Was it a wise decision to
only concentrate on smp performance as what seems to be the case and
is there going to be single processor improvements to come?

2 - stability, about 75% of my servers are fully stable on freebsd
5.3, on 4.x I have had no stability issues.  We have 1 server just
continously locking up, another one that has tcp stack problems (its
to do with the network side of things as locally it responds but goes
offline), and has to be rebooted every few weeks.

3 - robustness, 5.3 seems to not handle ddos attacks so well, I
remember on a 4.x machine I could easily take a full 100mbit udp flood
and have the server respond albeit maybe with some lag but it stayed
functional, 5.x seems to crumble under a lot less pressure on the same
machine.  This could be with pf been loaded on top of ipfw adding
extra overhead I dont know.

4 - compatiblity, I remember using 5.2.1 and pretty much all software
worked well in that and then they did the bind defaulting to base and
libs version jump, why wasnt this done in 5.0 so 3rd party apps could
adjust, now we have a situation where most stuff that worked in 4.x
worked well in 5.1 and 5.2.1 but then broke in 5.3 so effectively 5.3
was liek a new major version over 5.2.1.

I doubt I will be rolling back my server's as I know things will get
better over time but new server's we build I will expect to be
deploying 4.10 on them.  I just feel with the ULE scheduler stuff and
the IO performance issues I have heard about along with the issues I
have come across that 5.3 got rushed towards the end, and instead of
keeping 5.x as CURRENT they wanted 5.3 to be a production release so
disabled some things such as the ULE scheduler to force it to be
stable and its turned out a bit messy.  Has anyone else got comments
on my 4 main points?

Chris