freebsd stable - Dec 2003 - [SOLVED] RE: [Backtrace] 4.9 and 5.1-RELEASE occasionly panic

Hello!
> From:      Sten <sten@blinkenlights.nl>
>
> I'd really love getting rid of most hardcoded memory allocations
> in the fbsd kernel, with the main bugger being NMBCLUSTERS,
> which one always forgets about untill it's too late :(.
> In solaris auto-tuning has been a top priority for a long while,
> and propper dynamic tuning should get it right ( or even better )
> in 99% of the cases. People with other needs should be able
> to build a custom kernel.
 You need _not_ to build custom FreeBSD kernel in order to increase
NMBCLUSTERS. Both CURRENT and STABLE allows setting it from loader.conf:

kern.ipc.nmbufs="32768"         # Number of mbufs
kern.ipc.nmbclusters="16384"    # Number of mbuf clusters

But yes, you have to reboot your system if you want to raise them.

Sincerely, Dmitry
-- 
Atlantis ISP, System Administrator
e-mail:  dmitry@atlantis.dp.ua
nic-hdl: LYNX-RIPE

On Thu, 25 Dec 2003, Dmitry Pryanishnikov wrote:
>
> Hello!
>
> > From:      Sten <sten@blinkenlights.nl>
> >
> > I'd really love getting rid of most hardcoded memory allocations
> > in the fbsd kernel, with the main bugger being NMBCLUSTERS,
> > which one always forgets about untill it's too late :(.
> > In solaris auto-tuning has been a top priority for a long while,
> > and propper dynamic tuning should get it right ( or even better )
> > in 99% of the cases. People with other needs should be able
> > to build a custom kernel.
>
>  You need _not_ to build custom FreeBSD kernel in order to increase
> NMBCLUSTERS. Both CURRENT and STABLE allows setting it from loader.conf:
>
> kern.ipc.nmbufs="32768"         # Number of mbufs
> kern.ipc.nmbclusters="16384"    # Number of mbuf clusters
>
> But yes, you have to reboot your system if you want to raise them.
true, but my point is that these kind of static limits are kind
of silly. I have a machine with plenty of memory, when I start doing
serious network traffic it dies, ecause freebsd doesn't use available
memory. Static allocations are suboptimal and in corner cases they
lead to loss of network connectivity or crashes.
I do know that fixing these problems is a lot of work, which is
why I suggested it as a goal for 6.0.

to throw in a fully innapropriate quote :

<Linus> In other words, it's ok for a developer to say: "Ok, what
happens
if you do the above echo?" to figure out whether maybe the problem is due
to excessive spurgel-production in the VM frobnicator, but it is NOT OK to
say "you can tweak it for your use, so don't complain about the bad
behaviour"

-- 
Sten Spans

"There is a crack in everything, that's how the light gets in."
Leonard Cohen - Anthem