Architecture Diagrams

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01

GC-Induced HPA Thrash Cycle

Why CPU-based HPA and JVM GC are a dangerous combination. The feedback loop that takes 3 pods to 20 with zero real load.

01-gc-hpa-thrash-cycle.excalidraw Slide 10–11, 21
01

GC-Induced HPA Thrash Cycle

The GC pause → CPU spike → HPA false scale-out feedback loop.

01-gc-hpa-thrash-cycle.excalidraw Slide 10–11, 21
02

JVM Memory Regions Breakdown

Six JVM memory regions — only the heap is controlled by MaxRAMPercentage.

02-jvm-memory-regions.excalidraw Slide 6
03

AOT Cache Progression: CDS → AppCDS → Leyden

JDK 21 AppCDS → JDK 24 class linking → JDK 25 JIT profiles → JDK 26 ZGC support.

03-aot-cache-progression.excalidraw Slide 14, 16, 31
04

Container-Aware JVM Memory

Before: JVM reads host RAM, OOMKill. After: UseContainerSupport reads cgroup limits.

04-container-aware-jvm.excalidraw Slide 4–5
05

How Project Leyden Works

Three columns: Normal startup (all the work), training run (records it once), production (skips it).

05-how-project-leyden-works.excalidraw Slide 32
06

JVM Anti-Patterns vs Fixes

16 anti-patterns with exact fixes — Memory, GC, AOT/Startup, and Observability.

06-antipatterns-vs-fixes.excalidraw Slide 53–54
07

REST vs gRPC Protocol Comparison

Wire format, HTTP/2 connection model, and streaming comparison.

07-grpc-vs-rest.excalidraw Slide 34–37
08

RPC Architecture — REST at Boundary, gRPC Inside

When to use REST vs gRPC architecturally — public API boundary vs internal service mesh.

rpc-architecture.excalidraw Slide 34
09

REST Request Sequence — Per-Request Overhead

Full lifecycle of a single REST request showing DNS, TCP, TLS, HTTP overhead vs gRPC streaming.

rest-order-sequence.excalidraw Slide 34
10

GraphQL Query / Response Shape

GraphQL query and response shape — reference diagram for audiences evaluating REST vs GraphQL vs gRPC.

graphql-query-response.excalidraw Slide Reference