On Linux-Kernel Mailing List Behavior

As raised recently by Sarah Sharp, the Linux Kernel mailing list (lkml) has a reputation as an intimidating place.  The context (covered so well by LWN) was that Greg Kroah-Hartman, the stable maintainer, is seen as a soft touch who accepts patches Linus wouldn’t. There’s been much uninformed discussion from those outside lkml, so let’s …

6 Technical Things I Learned About Bitcoin

I’ve been collecting these as I research the bitcoin protocol, so I thought it was worth posting about.  None of these are groundbreaking, but these are what surprised me as I deepened my understanding. 10 Minute Blocks.  Currently 9 minutes.  But usually 7 minutes. Everyone talks about a block every 10 minutes, but that’s the …

VIRTIO Growing Up: OASIS Standard Technical Committee

http://www.oasis-open.org/committees/virtio Over the last few years, interest in virtio has begun compounding.  FreeBSD have their bhyve implementation, there’s an MMIO bus and SCSI endpoint implementation, and I’ve been fielding more queries about various alternate implementations.  While it’s taken longer than I’d hoped, the effort hasn’t waned as I feared. So I have carved out some …

GCC and C vs C++ Speed, Measured.

With the imminent release of gcc 4.8, GCC has finally switched to C++ as the implementation language.  As usual, LWN has excellent coverage.  Those with long memories will remember Linux trying to use g++ back in 1992 and retreating in horror at the larger, slower code.  The main benefit was stricter typechecking, particularly for enums (a …

Looking forward to linux.conf.au 2013

This year’s organizers took specific pains to attract deep content, and the schedule reflects that: there are very few slots where I’m not torn between two topics.  This will be great fun! After a little introspection, I did not submit a talk this year.  My work in 2012 was with Linaro helping with KVM on …

Fixed-length semi-lockless queues…

One of my vacation project was to look at a good queue implementation for ccan/antithread.  I read a few papers, which mainly deal with generic link-list-style queues (I got quite excited about one before I realized that it needed a 128-bit compare-and-swap for 64 bit machines).  I only really need a fixed-length queue of void …