pwillis-els

Heap dumping a Java process running in AWS ECS

Note: this guide is designed for AWS ECS services, but starting from Step 4 is functionally equivalent to any Docker container on a Linux host.

Step 1. Look up ECS service

1. Log into the AWS Console using the appropriate AWS account
2. Navigate to AWS ECS service clusters (https://console.aws.amazon.com/ecs/home)
3. Make sure you are in the correct region, if not, switch to the correct region (second drop-down menu in top right corner)
4. Select the correct cluster (ex: https://console.aws.amazon.com/ecs/home?region=us-east-1#/clusters//services)
5. In the Services tab, In the 'Filter in this page' text box, type the name of the service

jboner

Latency Comparison Numbers (~2012)
----------------------------------
L1 cache reference                           0.5 ns
Branch mispredict                            5   ns
L2 cache reference                           7   ns                      14x L1 cache
Mutex lock/unlock                           25   ns
Main memory reference                      100   ns                      20x L2 cache, 200x L1 cache
Compress 1K bytes with Zippy             3,000   ns        3 us
Send 1K bytes over 1 Gbps network       10,000   ns       10 us
Read 4K randomly from SSD*             150,000   ns      150 us          ~1GB/sec SSD