5d0efce278
After some investigation, it appears that SocketSet.Shutdown() and SocketSet.Close() are not synchronous operations. The sendto system call called in SocketSet.Shutdown() is not a blocking send. That means there is a race in which SocketSet.Shutdown() sends a message to a file descriptor to unblock select, while SocketSet.Close() will close the file descriptor that the message is being sent to. If SocketSet.Close() wins the race, select is listening on a dead file descriptor and will hang indefinitely. This is fixed in the current master by putting SocketSet.Close() inside of the goroutine in which data from the socket is being received. It relies on SocketSet.Shutdown() being called to terminate the goroutine. While this works most of the time, there is a race here. All the goroutines can also be terminated by a closeChan. If the goroutine receives an event (thus unblocking select) and then closeChan is triggered, both SocketSet.Shutdown() and SocketSet.Close() race, leading to undefined behavior. This patch ensures the ordering of the two function calls by pulling them both out of the goroutine and separating them with a WaitGroup. Co-authored-by: James Shubin <james@shubin.ca>
mgmt: next generation config management!
Community:
Come join us in the mgmt community!
| Medium | Link |
|---|---|
| IRC | #mgmtconfig on Freenode |
| @mgmtconfig & #mgmtconfig | |
| Mailing list | mgmtconfig-list@redhat.com |
| Patreon | purpleidea on Patreon |
| Liberapay | purpleidea on Liberapay |
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 developers should read the quick start guide.
Documentation:
Please read, enjoy and help improve our documentation!
| Documentation | Additional Notes |
|---|---|
| quick start guide | for mgmt developers |
| frequently asked questions | for everyone |
| general documentation | for everyone |
| language guide | for everyone |
| function guide | for mgmt developers |
| resource guide | for mgmt developers |
| style guide | for mgmt developers |
| godoc API reference | for mgmt developers |
| prometheus guide | for everyone |
| puppet guide | for puppet sysadmins |
| development | for mgmt developers |
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!
Roadmap:
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 see: TODO.md for a list of upcoming work and TODO items. Please get involved by working on one of these items or by suggesting something else!
Bugs:
Please set the DEBUG constant in main.go
to true, and post the logs when you report the issue.
Bonus points if you provide a shell
or OMV reproducible
test case.
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:
Read what people are saying and publishing about mgmt!
Happy hacking!