seaweedfs

Chris Lu 39ba19eea6 filer: async empty folder cleanup via metadata events (#7614 ) * filer: async empty folder cleanup via metadata events Implements asynchronous empty folder cleanup when files are deleted in S3. Key changes: 1. EmptyFolderCleaner - New component that handles folder cleanup: - Uses consistent hashing (LockRing) to determine folder ownership - Each filer owns specific folders, avoiding duplicate cleanup work - Debounces delete events (10s delay) to batch multiple deletes - Caches rough folder counts to skip unnecessary checks - Cancels pending cleanup when new files are created - Handles both file and subdirectory deletions 2. Integration with metadata events: - Listens to both local and remote filer metadata events - Processes create/delete/rename events to track folder state - Only processes folders under /buckets/<bucket>/... 3. Removed synchronous empty folder cleanup from S3 handlers: - DeleteObjectHandler no longer calls DoDeleteEmptyParentDirectories - DeleteMultipleObjectsHandler no longer tracks/cleans directories - Cleanup now happens asynchronously via metadata events Benefits: - Non-blocking: S3 delete requests return immediately - Coordinated: Only one filer (the owner) cleans each folder - Efficient: Batching and caching reduce unnecessary checks - Event-driven: Folder deletion triggers parent folder check automatically * filer: add CleanupQueue data structure for deduplicated folder cleanup CleanupQueue uses a linked list for FIFO ordering and a hashmap for O(1) deduplication. Processing is triggered when: - Queue size reaches maxSize (default 1000), OR - Oldest item exceeds maxAge (default 10 minutes) Key features: - O(1) Add, Remove, Pop, Contains operations - Duplicate folders are ignored (keeps original position/time) - Testable with injectable time function - Thread-safe with mutex protection * filer: use CleanupQueue for empty folder cleanup Replace timer-per-folder approach with queue-based processing: - Use CleanupQueue for deduplication and ordered processing - Process queue when full (1000 items) or oldest item exceeds 10 minutes - Background processor checks queue every 10 seconds - Remove from queue on create events to cancel pending cleanup Benefits: - Bounded memory: queue has max size, not unlimited timers - Efficient: O(1) add/remove/contains operations - Batch processing: handle many folders efficiently - Better for high-volume delete scenarios * filer: CleanupQueue.Add moves duplicate to back with updated time When adding a folder that already exists in the queue: - Remove it from its current position - Add it to the back of the queue - Update the queue time to current time This ensures that folders with recent delete activity are processed later, giving more time for additional deletes to occur. * filer: CleanupQueue uses event time and inserts in sorted order Changes: - Add() now takes eventTime parameter instead of using current time - Insert items in time-sorted order (oldest at front) to handle out-of-order events - When updating duplicate with newer time, reposition to maintain sort order - Ignore updates with older time (keep existing later time) This ensures proper ordering when processing events from distributed filers where event arrival order may not match event occurrence order. * filer: remove unused CleanupQueue functions (SetNowFunc, GetAll) Removed test-only functions: - SetNowFunc: tests now use real time with past event times - GetAll: tests now use Pop() to verify order Kept functions used in production: - Peek: used in filer_notify_read.go - OldestAge: used in empty_folder_cleaner.go logging * filer: initialize cache entry on first delete/create event Previously, roughCount was only updated if the cache entry already existed, but entries were only created during executeCleanup. This meant delete/create events before the first cleanup didn't track the count. Now create the cache entry on first event, so roughCount properly tracks all changes from the start. * filer: skip adding to cleanup queue if roughCount > 0 If the cached roughCount indicates there are still items in the folder, don't bother adding it to the cleanup queue. This avoids unnecessary queue entries and reduces wasted cleanup checks. * filer: don't create cache entry on create event Only update roughCount if the folder is already being tracked. New folders don't need tracking until we see a delete event. * filer: move empty folder cleanup to its own package - Created weed/filer/empty_folder_cleanup package - Defined FilerOperations interface to break circular dependency - Added CountDirectoryEntries method to Filer - Exported IsUnderPath and IsUnderBucketPath helper functions * filer: make isUnderPath and isUnderBucketPath private These helpers are only used within the empty_folder_cleanup package.	2 months ago
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http_down.go	test passed	6 years ago

filer: async empty folder cleanup via metadata events (#7614 )

* filer: async empty folder cleanup via metadata events

Implements asynchronous empty folder cleanup when files are deleted in S3.

Key changes:

1. EmptyFolderCleaner - New component that handles folder cleanup:
   - Uses consistent hashing (LockRing) to determine folder ownership
   - Each filer owns specific folders, avoiding duplicate cleanup work
   - Debounces delete events (10s delay) to batch multiple deletes
   - Caches rough folder counts to skip unnecessary checks
   - Cancels pending cleanup when new files are created
   - Handles both file and subdirectory deletions

2. Integration with metadata events:
   - Listens to both local and remote filer metadata events
   - Processes create/delete/rename events to track folder state
   - Only processes folders under /buckets/<bucket>/...

3. Removed synchronous empty folder cleanup from S3 handlers:
   - DeleteObjectHandler no longer calls DoDeleteEmptyParentDirectories
   - DeleteMultipleObjectsHandler no longer tracks/cleans directories
   - Cleanup now happens asynchronously via metadata events

Benefits:
- Non-blocking: S3 delete requests return immediately
- Coordinated: Only one filer (the owner) cleans each folder
- Efficient: Batching and caching reduce unnecessary checks
- Event-driven: Folder deletion triggers parent folder check automatically

* filer: add CleanupQueue data structure for deduplicated folder cleanup

CleanupQueue uses a linked list for FIFO ordering and a hashmap for O(1)
deduplication. Processing is triggered when:
- Queue size reaches maxSize (default 1000), OR
- Oldest item exceeds maxAge (default 10 minutes)

Key features:
- O(1) Add, Remove, Pop, Contains operations
- Duplicate folders are ignored (keeps original position/time)
- Testable with injectable time function
- Thread-safe with mutex protection

* filer: use CleanupQueue for empty folder cleanup

Replace timer-per-folder approach with queue-based processing:
- Use CleanupQueue for deduplication and ordered processing
- Process queue when full (1000 items) or oldest item exceeds 10 minutes
- Background processor checks queue every 10 seconds
- Remove from queue on create events to cancel pending cleanup

Benefits:
- Bounded memory: queue has max size, not unlimited timers
- Efficient: O(1) add/remove/contains operations
- Batch processing: handle many folders efficiently
- Better for high-volume delete scenarios

* filer: CleanupQueue.Add moves duplicate to back with updated time

When adding a folder that already exists in the queue:
- Remove it from its current position
- Add it to the back of the queue
- Update the queue time to current time

This ensures that folders with recent delete activity are processed
later, giving more time for additional deletes to occur.

* filer: CleanupQueue uses event time and inserts in sorted order

Changes:
- Add() now takes eventTime parameter instead of using current time
- Insert items in time-sorted order (oldest at front) to handle out-of-order events
- When updating duplicate with newer time, reposition to maintain sort order
- Ignore updates with older time (keep existing later time)

This ensures proper ordering when processing events from distributed filers
where event arrival order may not match event occurrence order.

* filer: remove unused CleanupQueue functions (SetNowFunc, GetAll)

Removed test-only functions:
- SetNowFunc: tests now use real time with past event times
- GetAll: tests now use Pop() to verify order

Kept functions used in production:
- Peek: used in filer_notify_read.go
- OldestAge: used in empty_folder_cleaner.go logging

* filer: initialize cache entry on first delete/create event

Previously, roughCount was only updated if the cache entry already
existed, but entries were only created during executeCleanup. This
meant delete/create events before the first cleanup didn't track
the count.

Now create the cache entry on first event, so roughCount properly
tracks all changes from the start.

* filer: skip adding to cleanup queue if roughCount > 0

If the cached roughCount indicates there are still items in the
folder, don't bother adding it to the cleanup queue. This avoids
unnecessary queue entries and reduces wasted cleanup checks.

* filer: don't create cache entry on create event

Only update roughCount if the folder is already being tracked.
New folders don't need tracking until we see a delete event.

* filer: move empty folder cleanup to its own package

- Created weed/filer/empty_folder_cleanup package
- Defined FilerOperations interface to break circular dependency
- Added CountDirectoryEntries method to Filer
- Exported IsUnderPath and IsUnderBucketPath helper functions

* filer: make isUnderPath and isUnderBucketPath private

These helpers are only used within the empty_folder_cleanup package.

2 months ago

http_down.go

test passed

6 years ago