Tutorial: FreeBSD network boot with mfsBSD (and pxelinux)

In this tutorial I am going to show how mfsBSD can be booted over the network. This tutorial expects the DHCP server (ISC) and TFTP server to be on a i386/amd64 FreeBSD machine using the same IP adress. If this is not the case, configuration may be different.

What do you need:

  • a boot server (DHCP, TFTP) with FreeBSD sources
  • mfsBSD (ISO from webpage or self-built)
  • some files from a installed sysutils/syslinux port (if you want pxelinux)
  • a network bootable (virtual) machine

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FreeBSD Compiler Benchmark: gcc-base vs. gcc-ports vs. clang

Many FreeBSD users (e.g. server admins) are interested in having their binaries run as fast as possible. There many options of improving the speed of the binaries – we can use different compilers and for each compiler different optimizations. But what combination is best for which processor?

We have benchmarked the perl binary compiled with gcc from the FreeBSD base system against gcc from ports and the new clang compiler. We have tested different optimizations on 8 different processors, all on the amd64 platform. The benchmark software we used is the perlbench benchmark running on Perl 5.12.3 on top of FreeBSD 8.2. This benchmark can also be used as a reference for users using other scripting languages (e.g. PHP, Python or Ruby) as these use similiar structures and methods.

We are benchmarking speed of the generated binaries, not the speed of compiling, as this is most important for us.
“Compile once, run many.” Continue reading

Backported patches for FreeBSD 8.2-RELEASE

FreeBSD 8.2-RELEASE was announced on February 24, 2011.

As we have been experiencing some problems we had to install several patches that didn’t make it into the release but I consider them important or useful. Most annoying was the swap panic problem, followed by two ZFS problems (page activation if using sendfile(2) and clock_t overflow), so we had to backport these patches to 8.2-RELEASE.
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Updated Tutorial: Debian GNU/kFreeBSD in a FreeBSD jail

In my last article about FOSDEM 2011 I wrote about visiting the Debian GNU/kFreeBSD presentation. What I was interested in – if it is possible to run this inside a FreeBSD jail or at least in a chroot. My results have been positive, so in this article I am providing a tutorial how to easily set up a Debian GNU/kFreeBSD jail on FreeBSD. Remember that the functionality may be limited.

Requirements: FreeBSD 8.1+ i386 or amd64, experience with FreeBSD and jail(8)
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Article in BSD Magazine: ZFS and FreeBSD

An article of mine with the title “ZFS and FreeBSD” was published in the February issue of the free online publication BSD Magazine. The target group of this magazine are users and friends of BSD operating systems.

The article summarizes the ZFS features, gives an overview of supported operating systems, provides links to useful resources and gives some FreeBSD tips.

Link to the free PDF issue: BSD Magazine 02/2011

FOSDEM 2011 – ZFS talk in BSD devroom

Last weekend (February 5th-6th) I visited the FOSDEM 2011 conference in Bruxelles, Belgium. The conference was crowded and many open source projects have been presenting their latest work. The FreeBSD project (where I am developer at) was present with a stand and I met several co-developers there. There have been lots of interesting talks, I was mainly interested in the Debian GNU/kFreeBSD presentation and the various MySQL and PostgreSQL talks – topics I deal with every day.

On Saturday, February 5th, I held a ZFS talk in the BSD devroom called “ZFS in Open Source Operating Systems” that was based on my previous talks.
Download PDF with presentation slides Continue reading

Talk at BSDDay 2010 in Budapest, Hungary

Last Saturday (20.11.2010) I attended the BSD Day 2010 at the Faculty of Informatics, Eötvös Loránd University in Budapest, Hungary. The event was sponsored by the Hungarian BSD Association and excellently organized by the hungarian FreeBSD developer Gábor Páli.

There have been several good talks including the talks of my friends Daniel Geržo (How the FreeBSD Project Works) and Roman Divácky (Clang/LLVM in the Base System).

My talk was “ZFS and FreeBSD“.
Presentation slides
Video recording from the presentation Continue reading

Viewing ZFS statistics with zfs-stats

The FreeBSD operating system collects statistical data from the ZFS subsystem using mechanisms originating from the OpenSolaris kstat framework.
This data is stored in sysctl variables (sysctl kstat.zfs). I have been recently working on improving a script named arc_summary.pl that was originally written by Ben Rockwood and modified by Jason J. Hellenthal. I have rewritten large parts of this script and renamed it to zfs-stats, as it’s output is not limited to ARC anymore. Continue reading

Help testing ZFS v28 in FreeBSD

Pawel Jakub Dawidek has released a patch [1] to test ZFS version 28 in FreeBSD development version (9-CURRENT).
The patch is highly experimental and not guaranteed to work correctly. We want to correct any bugs and issues related to this patch.

What is new in v28 (compared to v15)?

  • data deduplication
  • triple parity RAIDZ
  • removal of log devices
  • zfs diff
  • zpool split
  • snapshot holds

You can read more about various ZFS pool versions in my previous article [2]. Continue reading