Re: NetBSD-based file servers

[Hauke Fath <hauke%Espresso.Rhein-Neckar.DE@localhost>]

At 20:41 Uhr +0100 05.03.2012, Edgar Fuß wrote:

[I'll third the request for sane line lengths, for mail readers as well as
for customers like the gnats db]

>After the recent problems[*] we've been having with our (4.0/amd64) file
>server, I'll surely be facing the question why we're not using that other
>OS everybody else does.

As others have mentioned, netbsd-5, or even -6, might be a better choice
for a setup that pushes the envelope.

>So I need some data for that upcoming discussion. Who is using NetBSD to
>operate a file server on a scale comparable to or larger than ours, i.e.
>~200 users, ~1TB storage? If so, which version on what kind of hardware?

We run a file-server (mostly NFS, SMB, AFP, once pkg/46072 is resolved)
for ~80 users, who have their home on the server. The ~1.7 TB are served
from 8 SCSI disks off a MegaRAID 320-4X; the Super Micro X7SBE has two
PCI-X slots.

This setup was very stable under netbsd-5 (if for nothing else, with
partitions that size, you'd want something newer than netbsd-4 for the
journaled ffs...), until I went to optimise the RAID block size, and ran
into what became kern/46136. Lars Heidieker has been very helpful with
tweaking kernel parameters to cope with the load.

What I have taken away from this story, is that the NetBSD kernel is not
very constructive in the face of resource starvation. Processes get stuck,
and you can only guess about the reason, or hope that the pattern speaks to
somebody knowledgable. Kernel parameters are under-documented, and
real-life case descriptions are hard to find. I don't know how other OSes
behave in this situation.

Apart from that, I am pretty impressed with the overall stability of
netbsd-6. For me, it has been at least as solid as netbsd-5, which already
was a big improvement over netbsd-4 -- as a track record, this should earn
the project some confidence.  :)

HTH,
        hauke

-- 
Hauke Fath                        <hauke%Espresso.Rhein-Neckar.DE@localhost>
Friedrich-Ebert-Straße 70
64347 Griesheim
Germany