
JVM G1 and ZGC Tuning on AWS Corretto for ECS and EKS
Heap too small triggers G1 humongous allocations; too large balloons pause times on Graviton. Corretto on ECS/EKS/Lambda Java—when ZGC generational beats G1 for API heaps.
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Heap too small triggers G1 humongous allocations; too large balloons pause times on Graviton. Corretto on ECS/EKS/Lambda Java—when ZGC generational beats G1 for API heaps.

Consumer group rebalance storms stall processing longer than broker outages. This guide covers cooperative rebalancing, idempotent producers, and transactional reads on Amazon MSK—with when SQS FIFO is simpler.

FIFO guarantees shrink throughput—and unbounded queues only move backpressure to your AWS bill. Ordering, flow control, and Amazon MQ dead-letter patterns vs Kinesis resharding.

Packet loss on mobile networks still punishes HTTP/1.1 head-of-line blocking—but HTTP/3 only helps if CloudFront terminates QUIC and your origin connection pools are sized for multiplexed streams. This guide connects Reno, Cubic, BBR, HPACK, and QUIC to ALB and CloudFront decisions.

Local JWT validation is fast until revocation lags bite you. When to introspect at Cognito, use API Gateway JWT authorizers, and add Verified Permissions for fine-grained authz.

Serializable sounds safest until your checkout times out under row locks. This guide maps READ COMMITTED, REPEATABLE READ, and SERIALIZABLE to RDS/Aurora defaults—and when DynamoDB conditional writes are the BASE alternative.

Autovacuum cannot keep up after Black Friday bulk deletes—and your BRIN index is not helping point lookups. Vacuum strategy on Aurora, plus Aurora Limitless and DynamoDB hot key mitigation.

Token buckets allow bursts; leaky buckets smooth traffic—WAF rate rules and API Gateway usage plans implement neither perfectly but both matter for layered defense.

A full TLS handshake on every API call adds RTTs your p99 cannot afford. This guide walks TLS 1.3 1-RTT resumption, ACM cert rotation, and security policies on ALB and CloudFront.

Project Loom virtual threads help I/O-bound Java on ECS—not CPU-bound aggregation. Compare actor models, lock-free queues, and when Lambda concurrency beats pinning threads on EC2.

Control Tower gets you an org; it does not tell you how many OUs you need or which policy type owns VPC public access. Since re:Invent 2024 you have four layers — SCP, RCP, declarative, and tag policies — and RCP coverage grew through Feb 2026 (DynamoDB). A composite 60-account enterprise cut exception SCP attachments from 14 ad-hoc to 3 time-boxed RFCs in two quarters by moving accounts out of "temporary" prod OUs.

On June 10, 2026 AWS GA’d M9g/M9gd on Graviton5 — up to 25% more compute vs M8g, 35% faster for web and ML per AWS. Field guide: M9g vs M9gd, canary checklist, RI traps, and agentic-AI fit. Compute-optimized sibling C9g/C9gd GA June 30.