Ignored directories are still processed

[rfay]

DDEV has been very successful in using mutagen, and people love it. Thanks!

DDEV currently uses mutagen 0.17.2, and the classic environment is macOS filesystem as the alpha, and a docker container as the beta, actually syncing to a mounted docker volume.

In exploring a user's issues with polling inside the container, ddev/ddev#6286

I happened to discover behavior that was unexpected. I was using the ddev mutagen logs feature, which wraps mutagen daemon run with MUTAGEN_LOG_LEVEL=trace and I notice that files in ignored directories still cause mutagen to do things.

The key example is the .git directory of the project. I happened to do a git status on the host (alpha) and I see
2024-06-07 10:37:16.294341 [T] [sync.sync_06rS9JYw.alpha.watching] Processing event path: ".git/index.lock"

Further exploration showed that all git activities were monitored on the alpha.

Here's the description of the sync session:

Sync session in use

Mutagen: ok: 
--------------------------------------------------------------------------------
Name: d10
Identifier: sync_06rS9JYwiPlTvWhjUa9uBI9QctzRcdhAY2GQus9NlqC
Labels:
	com.ddev.config-hash: 70e61639ed0eb44cf5ff2c0010e6f0b827b42c30
	com.ddev.volume-signature: Users-rfay-lima-default-sock-1717777961
Configuration:
	Synchronization mode: Two Way Resolved
	Hashing algorithm: Default (SHA-1)
	Maximum allowed entry count: Default (2⁶⁴−1)
	Maximum staging file size: Default (18 EB)
	Symbolic link mode: POSIX Raw
	Ignore VCS mode: Default (Propagate)
	Ignores:
		/.git
		/.tarballs
		/.ddev/db_snapshots
		/.ddev/.importdb*
		.DS_Store
		.idea
		/web/sites/default/files
	Permissions mode: Default (Portable)
Alpha:
	URL: /Users/rfay/workspace/d10
	Configuration:
		Watch mode: Default (Portable)
		Watch polling interval: Default (10 seconds)
		Probe mode: Default (Probe)
		Scan mode: Default (Accelerated)
		Stage mode: Neighboring
		File mode: Default (0600)
		Directory mode: Default (0700)
		Default file/directory owner: Default
		Default file/directory group: Default
	Connected: Yes
	Synchronizable contents:
		7160 directories
		27681 files (136 MB)
		4 symbolic links
Beta:
	URL: docker://ddev-d10-web/var/www/html
		DOCKER_HOST=unix:///Users/rfay/.lima/default/sock/docker.sock
	Configuration:
		Watch mode: Default (Portable)
		Watch polling interval: Default (10 seconds)
		Probe mode: Default (Probe)
		Scan mode: Default (Accelerated)
		Stage mode: Neighboring
		File mode: Default (0600)
		Directory mode: Default (0700)
		Default file/directory owner: Default
		Default file/directory group: Default
		Compression: Default (DEFLATE)
	Connected: Yes
	Synchronizable contents:
		7160 directories
		27681 files (136 MB)
		4 symbolic links
Status: Watching for changes
--------------------------------------------------------------------------------

Here's the mutagen.yml:

mutagen.yml contents

#ddev-generated
# To override this file remove the line above
# and add your own configuration. If you override it you will
# probably want to check it in.
# Please do `ddev mutagen reset` after changing the file.
# See DDEV Mutagen docs at
# https://ddev.readthedocs.io/en/stable/users/install/performance/#mutagen
# For detailed information about mutagen configuration options, see
# https://mutagen.io/documentation/introduction/configuration
sync:
  defaults:
    mode: "two-way-resolved"
    stageMode: "neighboring"
    ignore:
      paths:
        # The top-level .git directory is ignored because where possible it's
        # mounted into the container with a traditional docker bind-mount
        - "/.git"
        - "/.tarballs"
        - "/.ddev/db_snapshots"
        - "/.ddev/.importdb*"
        - ".DS_Store"
        - ".idea"
        - "/web/sites/default/files"

        # You can also exclude other directories from mutagen-syncing
        # For example /var/www/html/var does not need to sync in TYPO3
        # so you can add:
        # - "/var"
        # vcs like .git can be ignored for safety, but then some
        # composer operations may fail if they use dev versions/git.
        # vcs: true
    symlink:
      mode: "posix-raw"

Trace content from git status:

Related trace content of git status

2024-06-07 10:42:13.734636 [T] [sync.sync_06rS9JYw.alpha.watching] Processing event path: ".git/index.lock"
2024-06-07 10:42:13.755793 [D] [sync.sync_06rS9JYw] Triggered by alpha endpoint
2024-06-07 10:42:13.757442 [D] [sync.sync_06rS9JYw] Scanning endpoints
2024-06-07 10:42:13.757498 [D] [sync.sync_06rS9JYw.beta] Using last snapshot bytes as baseline
2024-06-07 10:42:13.757500 [D] [sync.sync_06rS9JYw.alpha] Performing accelerated scan with 1 recheck paths
2024-06-07 16:42:13.773050 [D] [sync.sync_06rS9JYw.beta] Performing accelerated scan with existing snapshot
2024-06-07 10:42:13.777443 [D] [sync.sync_06rS9JYw.alpha] Saving cache to disk
2024-06-07 10:42:13.781882 [D] [sync.sync_06rS9JYw.beta] Snapshot delta yielded 1552043 bytes using 1 block operation(s) and 0 data operation(s) totaling 0 byte(s)
2024-06-07 10:42:13.802882 [T] [sync.sync_06rS9JYw] Ancestor contains 34845 entries, alpha contains 34845 entries, beta contains 34845 entries
2024-06-07 10:42:13.809974 [D] [sync.sync_06rS9JYw] Performing reconciliation
2024-06-07 10:42:13.894223 [T] [sync.sync_06rS9JYw.alpha.watching] Processing event path: ".git/index.lock"
2024-06-07 10:42:13.915310 [D] [sync.sync_06rS9JYw] Triggered by alpha endpoint
2024-06-07 10:42:13.916726 [D] [sync.sync_06rS9JYw] Scanning endpoints
2024-06-07 10:42:13.916761 [D] [sync.sync_06rS9JYw.beta] Using last snapshot bytes as baseline
2024-06-07 10:42:13.916775 [D] [sync.sync_06rS9JYw.alpha] Performing accelerated scan with 1 recheck paths
2024-06-07 16:42:13.932496 [D] [sync.sync_06rS9JYw.beta] Performing accelerated scan with existing snapshot
2024-06-07 10:42:13.943909 [D] [sync.sync_06rS9JYw.beta] Snapshot delta yielded 1552043 bytes using 1 block operation(s) and 0 data operation(s) totaling 0 byte(s)
2024-06-07 10:42:13.964937 [T] [sync.sync_06rS9JYw] Ancestor contains 34845 entries, alpha contains 34845 entries, beta contains 34845 entries
2024-06-07 10:42:13.971238 [D] [sync.sync_06rS9JYw] Performing reconciliation
2024-06-07 16:42:16.468898 [D] [sync.sync_06rS9JYw.beta] [polling] Received timer-based polling signal
2024-06-07 16:42:16.469037 [D] [sync.sync_06rS9JYw.beta] [polling] Performing filesystem scan
2024-06-07 16:42:16.603449 [D] [sync.sync_06rS9JYw.beta] [polling] Accelerated scanning now available
2024-06-07 16:42:16.614291 [D] [sync.sync_06rS9JYw.beta] [polling] No unignored modifications detected

Does the alpha actually monitor things and ignore them? Is that what's going on here? It seems like unexpected work.