Lock-Bypass Manager Speculative Execution Thread Contention
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Synchronization techniques in managed runtime environments consume processing resources, leading to increased execution time and CPU overhead due to the need for sequential thread execution and frequent lock acquisition and release, even when no contention exists between threads.
Innovation Solution
The implementation of a lock-bypass manager that conditionally applies object locks based on contention, intercepts lock requests, and leverages ISA-specific instructions for speculative execution, allowing for deferred or eliminated lock operations, thereby conserving processor resources and improving performance.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If synchronization techniques are employed to ensure thread-safe operation, then reliability is improved, but productivity deteriorates due to sequential execution and CPU overhead
Solution Approach 1:
The system dynamically determines whether to apply locking based on runtime conditions. The lock-bypass manager monitors for contention and selectively applies locks only when necessary, allowing the synchronization behavior to adapt between locked and unlocked states based on actual thread interaction patterns
Solution Approach 2:
The system changes the locking parameter from a static always-locked state to a dynamic state that transitions between locked and unlocked based on contention detection. This parameter change allows the system to optimize between safety and performance based on runtime conditions
2Reliability
If object locks are acquired and released frequently to ensure thread safety, then reliability is improved, but loss of time increases due to lock overhead
Solution Approach 1:
The system extracts the lock acquisition and release operations from the normal execution path and places them behind a conditional check. The lock-bypass manager intercepts lock requests and determines whether to actually perform the locking operation or bypass it entirely, removing unnecessary lock overhead from the critical path
Solution Approach 2:
The system performs preliminary detection of contention conditions before acquiring locks. By monitoring and detecting potential contention in advance, the system can proactively apply locks only when needed, preventing unnecessary lock acquisition and release operations
3Reliability
If synchronization is applied to all object accesses, then reliability is improved, but device complexity increases due to lock management overhead
Solution Approach 1:
The lock-bypass manager acts as an intermediary between the threading system and the lock management infrastructure. It intercepts lock requests, analyzes contention conditions, and makes intelligent decisions about whether to apply locking, thereby simplifying the overall lock management complexity while maintaining thread safety where needed
Data Source
AI summary
Example methods and apparatus to manage object locks are disclosed. A disclosed example method includes intercepting a processor request to apply the lock on the object, identifying a performance history of the object based on a number of instances of contention, reducing computing resources of the processor by, when the number of instances is below a threshold value, generating a lock bypass for the object to cause speculative execution of target code within the object, and preventing speculative execution by applying the lock on the object when the number of instances is above the threshold value.