better document DebugCollector internals #9484
Open
Conversation
This file contains hidden or bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
hawkw
reviewed
Dec 9, 2025
Comment on lines
+48
to
+81
| //! ```text | ||
| //! +------------------------+ +--------------+ +---------------+ | ||
| //! | dump device containing | | user process | | log files | | ||
| //! | kernel crash dump | +--------------+ | inside zones | | ||
| //! +------------------------+ | +---------------+ | ||
| //! | | | | ||
| //! | | process crash: | | ||
| //! | | system writes | | ||
| //! | DebugCollector | core dump to | | ||
| //! | invokes | configured | | ||
| //! | savecore(8) | directory | | ||
| //! | | | | ||
| //! | v | | ||
| //! | +--------------------------------------+ | | ||
| //! | | chosen "core" dataset | | | ||
| //! | | (ZFS dataset on internal (M.2) disk) | | | ||
| //! | +--------------------------------------+ | | ||
| //! | | | | ||
| //! | | | | ||
| //! | | | | ||
| //! | | DebugCollector | | ||
| //! | | periodically archives | | ||
| //! | | the core dumps and | | ||
| //! | | log files (copies to | | ||
| //! | | debug dataset, then | | ||
| //! | | deletes the original) | | ||
| //! | | | | ||
| //! v v v | ||
| //! +----------------------------------------------------------+ | ||
| //! | debug datasets (ZFS datasets on external (U.2) disks) |-+ | ||
| //! +----------------------------------------------------------+ |-+ | ||
| //! +----------------------------------------------------------+ | | ||
| //! +----------------------------------------------------------+ | ||
| //! ``` |
| //! directory we find: | ||
| //! | ||
| //! * `core.[zone-name].[exe-filename].[pid].[time]`: process core dumps | ||
| //! * `unix.[0-9]+`, `bounds`: files associated with kernel crash dumps |
Member
There was a problem hiding this comment.
what's bounds? it's a little ambiguous IMO whether or not this is saying there's exactly one file called bounds or multiple bounds.[0-9]+es?
Collaborator
Author
There was a problem hiding this comment.
I believe there is at most one file called bounds and any number of files matching the pattern unix.[0-9]+. The comment is deliberately vague about what the bounds file is because I don't know authoritatively and I don't think it's important here. (I believe savecore writes it out along with each dump it writes out and it contains the largest-numbered file so far so that the next time it runs it doesn't have to check for the existence of unix.0, unix.1, etc., but as I said I'm not positive.)
Sign up for free
to join this conversation on GitHub.
Already have an account?
Sign in to comment
Add this suggestion to a batch that can be applied as a single commit.
This suggestion is invalid because no changes were made to the code.
Suggestions cannot be applied while the pull request is closed.
Suggestions cannot be applied while viewing a subset of changes.
Only one suggestion per line can be applied in a batch.
Add this suggestion to a batch that can be applied as a single commit.
Applying suggestions on deleted lines is not supported.
You must change the existing code in this line in order to create a valid suggestion.
Outdated suggestions cannot be applied.
This suggestion has been applied or marked resolved.
Suggestions cannot be applied from pending reviews.
Suggestions cannot be applied on multi-line comments.
Suggestions cannot be applied while the pull request is queued to merge.
Suggestion cannot be applied right now. Please check back later.
This updates the Big Theory Statement on the DebugCollector and adds documentation to a bunch of constants and types in the
DebugCollector.I'm deliberately not changing anything meaningful in this PR. I'll keep doing some cleanup in follow-up PRs.
(Staged on #9479 so I'm keeping this "draft" so I don't land it early.)