Hammer gets versioned

Matthew Dillon is adding versioning support to Hammer; it’ll support in-place version upgrading.  The gory details of his current plan are available, with an interesting tidbit: Hammer directory lookups remain the same speed even with 2 billion files in a directory, while UFS will be O(N^3) speed after several hundred thousand.

More links 2008/11/12

I have a number of things to link which probably can all go together:

A way to learn git

Since DragonFly is switching to git instead of CVS, something handy is ‘eg’, or Easy Git. It’s a wrapper around git that makes the transition from CVS easier, or so it says. (via _hasso_ on EFNet #dragonflybsd) The linked page lists some alternate programs that are also designed to make git acclimation easier.

Automatic PFS creation

Michael Neumann has come up with a way to automatically create pseudo file systems (PFS) when mirroring a Hammer volume.  Previously, the destination/slave file system would have to be created first; this makes it Just Work.

This means Hammer data streams will be incompatible with versions before and after this change, but it’s not going to damage anything.  Introducing a versioning system into Hammer data streams is an available project…