To reduce latency in data transfer among EC2 instances, especially in high-performance computing (HPC) applications or applications requiring low network latency, using a placement group is the best approach:
Understanding Placement Groups:
A placement group in Amazon EC2 is a logical grouping of instances within a single Availability Zone. Using placement groups, you can achieve low-latency network performance necessary for tightly coupled node-to-node communication.
Types of Placement Groups:
Cluster Placement Group: Instances are physically located close together in the same Availability Zone to provide low-latency network performance.
Partition Placement Group: Instances are divided into logical segments called partitions, reducing the likelihood of simultaneous failures.
Spread Placement Group: Instances are placed on distinct underlying hardware to reduce correlated failures.
Creating and Using a Placement Group:
You can create a placement group using the AWS Management Console, AWS CLI, or AWS SDKs.
When launching instances, specify the placement group to ensure they are launched within the same group.
aws ec2 create-placement-group --group-name my-placement-group --strategy cluster
aws ec2 run-instances --image-id ami-12345678 --count 4 --instance-type c5.large --placement GroupName=my-placement-group
Relocating Existing Instances:
Stop the instances, modify the placement group settings, and then restart them. Note that not all instance types are supported within placement groups, so check the documentation for compatibility.
Placement Groups
Cluster Instances for Low-Latency
