Scope – Performance Efficiency

What is in scope?

The Performance Efficiency pillar of WAF++ addresses all technical and procedural dimensions that directly influence the performance of cloud workloads.

Compute & Scaling

Selection and validation of instance types and sizes
Auto-scaling configuration and testing for stateless workloads
Serverless architectures and managed services for variable load
Container resources (CPU/memory limits, requests in Kubernetes)

Databases & Persistence

Database performance baseline and slow query analysis
Index strategy for high-frequency read and write operations
Connection pool configuration and connection pool sizing
Storage I/O performance (disk type, IOPS, throughput)

Network & Delivery

CDN configuration for static and cacheable content
VPC endpoints and private endpoints for internal service communication
Network topology design and AZ affinity for latency-sensitive paths
DNS latency and connection reuse strategies

Caching

Distributed caching strategy (Redis, Memcached, managed cache services)
CDN caching for web content
Application-layer caching and in-process caching
Cache invalidation mechanisms and TTL policies

Observability & Governance

SLO definition and SLI instrumentation
Performance monitoring (P95/P99 latency, throughput, error rate)
Load test and stress test governance in the CI/CD process
Performance debt register and quarterly review process

What is not in scope?

Outside Scope	Why
Algorithm optimizations in code	Code-level performance is software development; WAF++ addresses infrastructure and architecture performance.
Full fault tolerance & recovery	RTO/RPO, backups, failover mechanisms → Reliability pillar.
Provider contract negotiations	Enterprise agreements and pricing negotiations → Procurement/Cost pillar.
Security design decisions	TLS configuration, authentication latency as a security requirement → Security pillar.
End-user device performance	Browser rendering, app performance on end devices is outside cloud infrastructure.

Outside Scope

Why

Algorithm optimizations in code

Code-level performance is software development; WAF++ addresses infrastructure and architecture performance.

Full fault tolerance & recovery

RTO/RPO, backups, failover mechanisms → Reliability pillar.

Provider contract negotiations

Enterprise agreements and pricing negotiations → Procurement/Cost pillar.

Security design decisions

TLS configuration, authentication latency as a security requirement → Security pillar.

End-user device performance

Browser rendering, app performance on end devices is outside cloud infrastructure.

Brownfield vs. Greenfield

Performance optimization in existing and new systems requires fundamentally different approaches.

Brownfield (existing systems)

Dimension	Challenge	Recommended approach
Compute Sizing	Instance types were never selected based on metrics; utilization data is absent.	Baseline period 2–4 weeks; then rightsizing analysis.
Auto-Scaling	Static capacity; scaling was never needed or never implemented.	Incrementally: first a monitoring phase, then ASG without aggressive scaling thresholds.
Database	Performance Insights never enabled; slow query backlog unknown.	Enable Insights → slow query analysis → optimize top-20 queries.
Caching	No cache or ad-hoc cache without a strategy.	Access pattern analysis → introduce cache layer → measure hit rate.
Debt Register	Many known performance problems, but nowhere documented.	Kickoff workshop: capture known problems → create register → prioritize.

Dimension

Challenge

Recommended approach

Compute Sizing

Instance types were never selected based on metrics; utilization data is absent.

Baseline period 2–4 weeks; then rightsizing analysis.

Auto-Scaling

Static capacity; scaling was never needed or never implemented.

Incrementally: first a monitoring phase, then ASG without aggressive scaling thresholds.

Database

Performance Insights never enabled; slow query backlog unknown.

Enable Insights → slow query analysis → optimize top-20 queries.

Caching

No cache or ad-hoc cache without a strategy.

Access pattern analysis → introduce cache layer → measure hit rate.

Debt Register

Many known performance problems, but nowhere documented.

Kickoff workshop: capture known problems → create register → prioritize.

Greenfield (new systems)

Dimension	Opportunity	Recommended approach
Compute Sizing	Sizing decisions can be planned data-driven from the start.	Benchmark profile of the application → conservative sizing → adjust after 2 weeks.
Auto-Scaling	Auto-scaling can be planned from the beginning and validated immediately.	Stateless architecture first; validate auto-scaling in the load test phase.
SLOs	SLOs can be defined before the first deployment.	SLOs as part of the definition of done; instrument monitoring before go-live.
Load Tests	CI/CD integration can be set up from day 1.	Write load test scripts in the first sprint; set acceptance criteria before first users.

Dimension

Opportunity

Recommended approach

Compute Sizing

Sizing decisions can be planned data-driven from the start.

Benchmark profile of the application → conservative sizing → adjust after 2 weeks.

Auto-Scaling

Auto-scaling can be planned from the beginning and validated immediately.

Stateless architecture first; validate auto-scaling in the load test phase.

SLOs

SLOs can be defined before the first deployment.

SLOs as part of the definition of done; instrument monitoring before go-live.

Load Tests

CI/CD integration can be set up from day 1.

Write load test scripts in the first sprint; set acceptance criteria before first users.

Performance Driver Overview

Driver	Typical Symptom	Root Cause	WAF-PERF Control
Compute Bottleneck	High CPU/memory utilization, elevated P99 latency	Instance too small or wrong generation	WAF-PERF-010
Missing Elasticity	Service responds slowly during load spikes	No or incorrectly configured auto-scaling	WAF-PERF-020
Cache Miss Flood	High database utilization, high API latency	No cache or low hit rate	WAF-PERF-030
Slow Queries	Database CPU spike, connection pool exhausted	Missing indexes, full table scans	WAF-PERF-040
Unknown P99 Latency	SLA violations go unnoticed	No SLO monitoring, only average values	WAF-PERF-050
Performance Regression	New version worse than previous	No automated load test in CI/CD	WAF-PERF-060
High Network Latency	Unexpected latencies in microservice calls	Cross-AZ traffic, no CDN, no VPC endpoint	WAF-PERF-070
Cold Start Latency	First requests after idle are slow	Lambda/function without warmup configuration	WAF-PERF-080
Storage I/O Saturation	Database latency spikes despite normal CPU	gp2 burst depletion, wrong disk type	WAF-PERF-090
Known Problems Ignored	Same performance incidents repeat	No performance debt register	WAF-PERF-100

Driver

Typical Symptom

Root Cause

WAF-PERF Control

Compute Bottleneck

High CPU/memory utilization, elevated P99 latency

Instance too small or wrong generation

WAF-PERF-010

Missing Elasticity

Service responds slowly during load spikes

No or incorrectly configured auto-scaling

WAF-PERF-020

Cache Miss Flood

High database utilization, high API latency

No cache or low hit rate

WAF-PERF-030

Slow Queries

Database CPU spike, connection pool exhausted

Missing indexes, full table scans

WAF-PERF-040

Unknown P99 Latency

SLA violations go unnoticed

No SLO monitoring, only average values

WAF-PERF-050

Performance Regression

New version worse than previous

No automated load test in CI/CD

WAF-PERF-060

High Network Latency

Unexpected latencies in microservice calls

Cross-AZ traffic, no CDN, no VPC endpoint

WAF-PERF-070

Cold Start Latency

First requests after idle are slow

Lambda/function without warmup configuration

WAF-PERF-080

Storage I/O Saturation

Database latency spikes despite normal CPU

gp2 burst depletion, wrong disk type

WAF-PERF-090

Known Problems Ignored

Same performance incidents repeat

No performance debt register

WAF-PERF-100