Hammer and Hammer2 details

I haven’t been drawing enough attention to it, but there’s been a bunch of HAMMER filesystem activity lately: First, Tomohiro Kusumi has been working on HAMMER – these posts are a small subset of his commits.  Second, Matthew Dillon has been working full steam ahead on HAMMER2.  The HAMMER2 design document has been updated (read this!), and he’s already accomplished master->slave disk syncing.

It’s not ready for production, of course, which you may already realize, so don’t install it unless you want to work on the code.

V4-mapped addresses out, TCP MTU discovery in

Sepherosa Ziehau has posted a note that V4-mapped addressing is no longer supported in DragonFly.  You will need to do a full buildworld/buildkernel if you are running master.  Also, TCP MTU path discovery is on by default.  Also also, he’s added a SOL_SOCKET/SO_CPUINT socket option for use to reduce load in heavy network activity.  As usual, I don’t quite comprehend.

Installworld, no matter what

It’s possible, if you are several releases (years) behind, to end up with a DragonFly system that can’t compile and install the current release, due to incremental changes over time.  It’s rare, but it could happen now between, say, version 3.4 and 4.0.  The usual solution would be to incrementally upgrade in order, which is a lot of building and updating.  The alternative is the new installworld-force option from Matthew Dillon that forces a new set of binaries into place.  Use as a last resort.

A pile of DragonFly commits

In an effort to reduce my backlog of DragonFly things to post about, here’s quick notes: