Hadoop expertise on call, for clusters that still have to run

Overview

Hadoop operational expertise has been leaving the market for years, but the clusters are still in production and still carry regulated workloads. AceMQ provides named senior engineers, 24/7, for the clusters that have to keep running until the migration finishes.

Challenge

Common production incidents include a single queue consuming the cluster because its capacity and maximum-capacity settings were never reconciled, applications stuck in ACCEPTED because the ApplicationMaster resource percentage is exhausted, NodeManagers marked unhealthy from full local directories, and containers killed for exceeding physical memory when the real problem is JVM overhead outside the heap. These are diagnosable in minutes by someone who has seen them and can take days by someone who has not.

Environment

On-premises Hadoop clusters running YARN with Capacity or Fair Scheduler, mixed Spark, Hive, and MapReduce workloads.

Approach

AceMQ engineers work from ResourceManager and NodeManager logs, scheduler queue metrics, and container exit codes to separate a scheduling problem from a resource problem from a node problem. Stabilization comes first, followed by the queue configuration or memory sizing change that removes the recurrence.

Solution

• 15-minute emergency SLA with named senior engineers, 24/7, no tier-1 triage
• Queue capacity, maximum-capacity, and user-limit-factor review to resolve starvation and unbounded queue growth
• Diagnosis of applications stuck in ACCEPTED, including ApplicationMaster resource percentage exhaustion
• NodeManager health diagnosis covering local and log directory exhaustion and disk failure thresholds
• Container memory sizing across heap, overhead, and vmem ratio to stop kills that are really JVM overhead
• Preemption and node labeling configuration where mixed workloads must share a cluster with differing priorities

Outcome

Technologies