Verifying if a memory limit is sufficient
After configuring an appropriate memory limit with --memory_limit_hard_bytes, run a workload and
monitor the Kudu tablet server process’s RAM usage. The memory usage should stay around 50-75%
of the hard limit, with occasional spikes above 75% but below 100%. If the tablet server runs
above 75% consistently, the memory limit should be increased.
Service unavailable: Soft memory limit exceeded (at 96.35% of capacity)
And watch the memory rejections metrics:
-
leader_memory_pressure_rejections -
follower_memory_pressure_rejections -
transaction_memory_pressure_rejections
Occasional rejections due to memory pressure are fine and act as backpressure to clients. Clients will transparently retry operations. However, no operations should time out.
