DragonFly’s tcp keepalive was changed from milliseconds to seconds. This happened in both DragonFly-current and in the 5.6 release, and it changes the networking API, which means a dports rebuild is needed… or a pkg upgrade, for which happily all packages have been rebuilt. So, on your next update of the system, be sure to update packages too.
OPIE was disabled recently in DragonFly. Now that the 5.6 release is out, it has been removed. This may require manual intervention if you are on DragonFly-master (i.e. 5.5. or 5.7) and update in the next day or two. This need to fiddle with it will go away soon with changes to ‘make upgrade’; I will mention it when I see it.
This won’t affect anyone running 5.4 or 5.6. It’s only in development.
It’s possible to have data corrupted on a HAMMER2 volume during a specific combination of a bulkfree operation and a lot of writing to disk. Matthew Dillon has a potential fix already. As he announced, it’s scheduled to go into 5.4 this weekend. It’s a rare bug, but if you want to check for it, look for CHECK FAIL entries in /var/log/messages.
And because every cloud has a silver lining: some not-yet-quantified performance improvements.
It’s turned off and on by the sysctl machdep.isolated_user_pmap – and defaults to on for Intel CPUs. Buildworld tests show about a 4-5% performance hit, but that’s only one form of activity, measured, so there will surely be other effects.
Note that Spectre is not mitigated by this commit series, and as I understand it, cannot be realistically fixed in software.
Update: Matthew Dillon posted a summary to users@.
Update 2: He told us so.
SSH in DragonFly 5, by default, does not make a password authentication request on outgoing ssh sessions. You can manually add the option or change the config. Or use public keys, which is really the best idea if at all possible.
DragonFly 4.8 has been updated to 4.8.1, bringing in a lot of small fixes. Improved Intel video support and the virtio_scsi driver will be of most interest, I think. The 4.8.1 tag commit has all the details. You can update the normal way, and if you need an install image, I’ve uploaded them and they should appear at your local mirror.
Recent changes for virtual machine support and the new powerd utility have been rolled into the release branch for DragonFly. They’ll probably be in the next point release, or you can rebuild a release machine now for immediate access.
Also mentioned in the update from Matthew Dillon, DragonFly-master users should upgrade carefully as DragonFly migrates to using LibreSSL in base, and dports-based LibreSSL in dports.
Because this always happens just after I create a DragonFly release, there’s a new version of OpenSSL. However, this is for version 1.0.2. 1.0.1 is what’s in the release, and it’s supported through the end of the year.
OpenSSH has a major version bump in DragonFly, to 7.3p1. This means some features – specifically patches for High Performance Networking – are no longer there, and you’ll get an error if your config file requires them. Either remove the options from your config, or install OpenSSH from dports.
I’m a bit late on this, but: If you are using DragonFly-current, you will need to rebuild world. If you are on 4.4, this won’t matter until you go to 4.6, and you’d be rebuilding world and kernel for that anyway.
(4.6 will probably be tagged this weekend.)
If you are running bleeding-edge DragonFly, Sepherosa Ziehau has made some networking changes that both reduce CPU usage in high-traffic situations and change some underlying network structures. This means a full buildworld is needed on your next update.
If you’re using DragonFly 4.4.x or older, you are unaffected.