Video and USB fix

Matthew Dillon has written a contiguous memory mapper, which is designed to fix problems with video cards and USB drives that need a big chunk of memory to keep.  This can affect booting or later on, when disconnecting/reconnecting a USB drive.  If this still doesn’t fix the problem for you, try adjusting the sysctl ‘vm.dma_reserved’ to something bigger, like 64M.  It defaults to 16M.

(Normal mailarchive isn’t updating because of an ongoing upgrade to crater.dragonflybsd.org – sorry!)

What to do with /usr/obj

When building world and kernel on DragonFly, /usr/obj is where the work files get placed.  This can eat a bit of space, but it can be safely deleted.  If you keep the files around, subsequent rebuilds can be done faster with a quickwork/quickkernel, but this may not matter to you.

(This was answered on the mailing lists by Max Herrgaard, but I don’t have a link to his reply – sorry!)

Huge speed improvements, plus graphs

The two things that make my day!   The work on DragonFly-current has led to some significant speed improvements.  So good, that Samuel Greear’s post on OSNews.org links to graphed results from him and from Francois Tigeot (multi-page PDF) showing the results from pgbench.

The results show a jump in multi-core/processor numbers that vastly exceeds DragonFly 2.10’s performance, and is comparable to FreeBSD 9/10.  Here’s some of what did it.

HEADS UP: package recompilation needed

The presence of /usr/include/crypt.h in DragonFly (starting in December 2010) meant that some programs compiled during that time will expect that file to always be there.  It was recently removed, so any programs compiled in that timeframe will also need to be recompiled.  Right now, this affects you only if you are running DragonFly 2.13 , since that’s the only place crypt.h was removed.  This may be an issue for the release, but we’ll worry about that when we get there…  I’m kicking off new 2.13 bulk builds now.