If you are like me and have a long weekend, dig into /usr/share/examples. Not all of it is necessarily up to date, but there’s examples there on running rconfig, diskless, different pf and ipfw examples, and so on. Actual documentation is in corresponding man pages – and there’s examples on how to write them, too.
I just wasted an hour trying to figure out why xorg had strange output but no errors on this laptop, and it’s because I had i915_load=”YES” in /boot/loader.conf instead of i915_load=”YES” in /etc/rc.conf. I’m almost nearly sure I’ve mentioned that before, but if not: here you go.
(though if you never plan to run X, you can put it in loader.conf and everything will just work.)
(Title updated for a more correct sentence)
Welcome new DragonFly committer, Peeter Must!
Do you have a terabyte or more of RAM? You can boot DragonFly. In theory over 32 terabytes will require changes – but oh, to have such problems…
Noted from this commit: if you are routing over IPv6 directly to another address, the sysctl net.inet6.icmp6.nd6_onlink_ns_rfc4861 must be set to 1.
rdist has been removed. Does anyone mind? I don’t think so.
sys_pipe has been modified to avoid contention on DragonFly, which means better performance as tasks get handed between processors. See the commit message for details.
Matthew Dillon has added KVABIO, an API for avoiding the need to sync the TLB across all CPUs before continuing. What’s this mean? The more CPUs you are dealing with, the longer it takes to make sure all of them have the same cached view of the virtual memory. There’s a tradeoff – caching that view speeds up memory access, but the time cost of the synchronization can erase those benefits.
This API is now supported for NVMe and swap, HAMMER2, and tmpfs. Note that those last two links show a huge drop in IPI messaging. In the real world, this showed about a 5% improvement in performance for CPU-intensive work like complete synth builds. (Based on IRC conversations.)
This is a bugfix release, adding HAMMER2 support in initrd, among other cleanup commits. The tag message lists the changes. There’s no huge changes, but it’s only a bugfix release.
A writeup that may help someone in the future: if you decide you want to encrypt your /home directory, on DragonFly, this is how you do it.
I’ve got a long backlog of things to link to, so here’s the start: ifconfig now has an ‘lscan’ option, to show long SSIDs. “Long” means 14+ characters, in this case.
(Can you use emoji to create a SSID? That breaks character count and it’s just plain hard to read. Hmm.)
You can make them, but you can’t mount them. Tomohiro Kusumi’s note that mkfs_hammer2 works on Linux is of little wide practical use, but it’s a sign of progress to a larger goal.
I should have linked this with yesterday’s post: Sepherosa Ziehau put together some extended benchmarks on his changes between DragonFly 4.8 and 5.0, and their effects on latency using nginx to serve a lot of requests.
An optimization that applies to you only if you are on DragonFly, running nginx, and dealing with many requests: there’s a sysctl that specifically increases available sockets, which will decrease latency; Sepherosa Ziehau’s commit message gives stats.