790b7199ca
This mega patch primarily introduces a new function engine. The main reasons for this new engine are: 1) Massively improved performance with lock-contended graphs. Certain large function graphs could have very high lock-contention which turned out to be much slower than I would have liked. This new algorithm happens to be basically lock-free, so that's another helpful improvement. 2) Glitch-free function graphs. The function graphs could "glitch" (an FRP term) which could be undesirable in theory. In practice this was never really an issue, and I've not explicitly guaranteed that the new graphs are provably glitch-free, but in practice things are a lot more consistent. 3) Simpler graph shape. The new graphs don't require the private channels. This makes understanding the graphs a lot easier. 4) Branched graphs only run half. Previously we would run two pure side of an if statement, and while this was mostly meant as an early experiment, it stayed in for far too long and now was the right time to remove this. This also means our graphs are much smaller and more efficient too. Note that this changed the function API slightly. Everything has been ported. It's possible that we introduce a new API in the future, but it is unexpected to cause removal of the two current APIs. In addition, we finally split out the "schedule" aspect from world.schedule(). The "pick me" aspects now happen in a separate resource, rather than as a yucky side-effect in the function. This also lets us more precisely choose when we're scheduled, and we can observe without being chosen too. As usual many thanks to Sam for helping through some of the algorithmic graph shape issues!
mgmt: next generation config management!
Tip
Tip
About:
Mgmt is a real-time automation tool. It is familiar to existing configuration
management software, but is drastically more powerful as it can allow you to
build real-time, closed-loop feedback systems, in a very safe way, and with a
surprisingly small amount of our mcl code. For example, the following code
will ensure that your file server is set to read-only when it's friday.
import "datetime"
$is_friday = datetime.weekday(datetime.now()) == "friday"
file "/srv/files/" {
state => $const.res.file.state.exists,
mode => if $is_friday { # this updates the mode, the instant it changes!
"0550"
} else {
"0770"
},
}
It can run continuously, intermittently, or on-demand, and in the first case, it will guarantee that your system is always in the desired state for that instant! In this mode it can run as a decentralized cluster of agents across your network, each exchanging information with the others in real-time, to respond to your changing needs. For example, if you want to ensure that some resource runs on a maximum of two hosts in your cluster, you can specify that as well:
import "sys"
import "world"
# we'll set a few scheduling options:
$opts = struct{strategy => "rr", max => 2, ttl => 10,}
# schedule in a particular namespace with options:
$set = world.schedule("xsched", $opts)
if sys.hostname() in $set {
# use your imagination to put something more complex right here...
print "i got scheduled" {} # this will run on the chosen machines
}
As you add and remove hosts from the cluster, the real-time schedule function
will dynamically pick up to two hosts from the available pool. These specific
functions aren't intrinsic to the core design, and new ones can be easily added.
Please read on if you'd like to learn more...
Community:
Come join us in the mgmt community!
| Medium | Link |
|---|---|
| Matrix | #mgmtconfig on Matrix.org |
| IRC | #mgmtconfig on Libera.Chat |
| @mgmtconfig & #mgmtconfig | |
| Mailing list | looking for a new home, suggestions welcome |
| Patreon | purpleidea on Patreon |
Status:
Mgmt is a next generation automation tool. It has similarities to other tools in the configuration management space, but has a fast, modern, distributed systems approach. The project contains an engine and a language. Please have a look at an introductory video or blog post.
Mgmt is a fairly new project. It is usable today, but not yet feature complete. With your help you'll be able to influence our design and get us to 1.0 sooner! Interested users should read the quick start guide.
Documentation:
Please read, enjoy and help improve our documentation!
| Documentation | Additional Notes |
|---|---|
| quick start guide | for everyone |
| frequently asked questions | for everyone |
| general documentation | for everyone |
| resource reference | for everyone |
| function reference | for everyone |
| language guide | for everyone |
| function guide | for mgmt developers |
| resource guide | for mgmt developers |
| style guide | for mgmt developers |
| contributing guide | for mgmt contributors |
| service API guide | for external developers |
| godoc API reference | for mgmt developers |
| prometheus guide | for everyone |
| puppet guide | for puppet sysadmins |
| development | for mgmt developers |
| videos | for everyone |
| blogs | for everyone |
Questions:
Please ask in the community! If you have a well phrased question that might benefit others, consider asking it by sending a patch to the FAQ section. I'll merge your question, and a patch with the answer!
Get involved:
Feel free to grab one of the straightforward #mgmtlove issues if you're a first time contributor to the project or if you're unsure about what to hack on! Please get involved by working on one of these items or by suggesting something else! There are some lower priority issues and harder issues available in our TODO file. Please have a look.
Bugs:
Please set the DEBUG constant in main.go
to true, and post the logs when you report the issue.
Feel free to read my article on debugging golang programs.
Patches:
We'd love to have your patches! Please send them by email, or as a pull request.
On the web:
Blog posts and recorded talks about mgmt are listed here!
Happy hacking!