Reverts entity data without locking for better performance #1452
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@coderabbitai full review please |
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@shubham1g5: I will perform a full review of the PR. ✅ Actions performedFull review triggered. |
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Actionable comments posted: 1
🧹 Outside diff range and nitpick comments (1)
src/main/java/org/commcare/cases/entity/AsyncEntity.java (1)
138-138: Document the locking strategyThe class uses a complex locking strategy with both database-level locks and object-level synchronization. While there's a comment about lock ordering, it would be valuable to add comprehensive documentation about:
- The exact order of lock acquisition
- Why this order prevents deadlocks
- Which operations require which locks
Add a class-level documentation block like:
/** * Threading Model: * This class uses two levels of locking: * 1. Database-level locking (via EntityStorageCache) * 2. Object-level locking (via mAsyncLock) * * Lock Ordering: * To prevent deadlocks, locks must be acquired in the following order: * 1. First acquire the database lock (via lockCache()) * 2. Then acquire the object lock (via synchronized(mAsyncLock)) * * Operations requiring both locks: * - Writing to the cache * - Reading from the cache when value isn't in memory * * Operations requiring only object lock: * - Reading/writing in-memory values */
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📒 Files selected for processing (1)
src/main/java/org/commcare/cases/entity/AsyncEntity.java(1 hunks)
🔇 Additional comments (1)
src/main/java/org/commcare/cases/entity/AsyncEntity.java (1)
Line range hint 138-179: Verify performance impact of lock changes
While the changes aim to improve performance by avoiding unnecessary locks, we should verify the actual impact on loading times, especially for the mentioned case of 10,000 entries.
Run the following script to analyze lock-related patterns in the codebase:
| if (sortData[i] != null) { | ||
| return sortData[i]; | ||
| } |
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Fix thread safety issue in early return check
The early return check of sortData[i] is not thread-safe. Without proper synchronization, changes to sortData[i] made by other threads may not be visible due to the Java Memory Model's visibility guarantees.
Apply this diff to fix the thread visibility issue:
- if (sortData[i] != null) {
- return sortData[i];
- }
+ synchronized (mAsyncLock) {
+ if (sortData[i] != null) {
+ return sortData[i];
+ }
+ }📝 Committable suggestion
‼️ IMPORTANT
Carefully review the code before committing. Ensure that it accurately replaces the highlighted code, contains no missing lines, and has no issues with indentation. Thoroughly test & benchmark the code to ensure it meets the requirements.
| if (sortData[i] != null) { | |
| return sortData[i]; | |
| } | |
| synchronized (mAsyncLock) { | |
| if (sortData[i] != null) { | |
| return sortData[i]; | |
| } | |
| } |
Technical Summary
Return entity data if available without extra overhead caused by aquiring a db lock. This cuts the loading time of a 10k case list by half when already cached.
Safety Assurance
Safety story
I can't imagine us needing a lock just to return a set variable which is all this PR does.
Automated test coverage
NA
QA Plan
None
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Summary by CodeRabbit
New Features
Bug Fixes