HDFS-17896. Move logAllocatedBlock out of lock to reduce latency#8360
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CapMoon wants to merge 1 commit intoapache:trunkfrom
Open
HDFS-17896. Move logAllocatedBlock out of lock to reduce latency#8360CapMoon wants to merge 1 commit intoapache:trunkfrom
CapMoon wants to merge 1 commit intoapache:trunkfrom
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HDFS-17896. Move logAllocatedBlock out of lock in FSNamesystem.getAdditionalBlock to reduce latency
Description of PR
The logAllocatedBlock method in FSNamesystem.getAdditionalBlock is currently called while holding global lock. Flame graph analysis shows this logging path (via SLF4J/Log4j appenders) contributes non-trivial latency, blocking other NameNode operations.
Since logAllocatedBlock is only for audit/diagnostic logging and does not modify shared state, we can safely move it after releasing global lock to reduce lock hold time and improve write throughput.
This change preserves all existing logging behavior while eliminating unnecessary lock contention from I/O-bound logging operations.
How was this patch tested?
N/A