[CASSANDRA-14163] RateBasedBackPressure unnecessarily invokes a lock on the Guava RateLimiter

• Type: Improvement
• Status: Resolved
• Priority: Low
• Resolution: Fixed
• Fix Version/s: 3.11.3, 4.0-alpha1, 4.0
• Component/s: Legacy/Core
• Labels: lhf
• Assignee: Nate McCall
• Reporter: Nate McCall

Authors

Nate McCall

Reviewers

Jason Brown

• Created: 11/Jan/18 21:34
• Updated: 15/May/20 08:03
• Resolved: 17/Feb/18 15:32

Description

o.a.c.net.RateBasedBackPressure#apply calls getRate() on the underlying Guava RateLimiter several times in quick succession (including as the argument to a non level checked log statement).

Said getRate() method acquires a lock within RateLimiter, so just getting a local variable reference will remove several calls and thus several lock acquisitions.