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126 questions, 454 terms and 400 topics in 20 areas.
60 results for “Reliability vs Complexity”
Cost vs Reliability Trade-off
The non-linear relationship between availability and spend, which makes each additional nine roughly an order of magnitude more expensive.
Durability vs Availability
Two different storage guarantees — whether data survives, and whether it can be reached right now — routinely conflated because both are quoted in nines.
Monolith vs Microservices
A trade of deployment independence against distributed-systems complexity, decided by team topology far more often than by technology.
Active-Active vs Active-Passive
Whether all regions serve traffic simultaneously, or one serves while another waits to take over — a choice about which failure mode you would rather have.
Build vs Buy
The choice between developing a capability in-house and acquiring it, decided on differentiation and total cost rather than on feature lists.
Containment vs Eradication
Stopping an attacker's ongoing access versus removing their foothold entirely — sequential phases with different urgency and different risks of doing them wrong.
Delivery vs Maintainability
Choosing where to take deliberate shortcuts, based on which kinds of debt are cheap to repay and which compound.
ETL vs ELT
Whether data is transformed before loading into the target or after it, which decides where the compute happens and how much raw history you keep.
Fail-Fast vs Fail-Safe
Whether a component should stop immediately on detecting a problem, or continue in a degraded but safe mode — a choice that depends entirely on which outcome is worse.
Horizontal vs Vertical Scaling
Adding more machines versus making one machine bigger — and the fact that vertical is underrated for stateful tiers.
Layer 4 vs Layer 7 Load Balancing
Balancing on connection metadata (IP and port) versus on the content of the request (path, host, headers).
Managed vs Self-Managed
Trading control, portability and unit cost against the operational burden of running the thing yourself.
OLTP vs OLAP
Two workload shapes with opposite requirements — many small indexed transactions versus few large scans and aggregations — which is why they belong in different stores.
Operational vs Analytical Store
The separation between the store serving the application's transactions and the one serving reporting and analysis, and the mechanism connecting them.
Provisioned vs Serverless Capacity
Paying for a fixed database size continuously, versus paying for capacity consumed with automatic scaling — a crossover decision driven by duty cycle.
Re-architect vs Rebuild
Restructuring an existing system incrementally versus writing a replacement from scratch — and the strong evidence that incremental wins.
SQL vs NoSQL
A choice driven by access patterns, consistency requirements and query flexibility — not by data volume, which is the reason usually given.
Security vs Usability
A trade-off that is usually resolved by varying the control with the value of the action, rather than by choosing a uniform level of friction.
Strong vs Eventual Consistency
A per-operation decision, not a per-system one: whether this specific read must reflect every completed write.
Synchronous vs Asynchronous Communication
Whether the caller waits for the callee's answer — decided by whether the caller's outcome depends on it, not by latency or taste.
Synchronous vs Asynchronous Replication
Whether a write is acknowledged only after a replica has it, trading write latency against the amount of data a failure can lose.
Zonal vs Regional Services
Whether a cloud resource lives in one availability zone or is inherently spread across several — a property that determines what a zone failure takes with it.
Abstraction
Exposing what a component does while hiding how it does it, so callers depend on the contract rather than the mechanism.
Availability Calculation
Deriving a system's availability from its components, remembering that dependencies in series multiply.
Blameless Postmortem
An incident review that seeks the systemic conditions that made a failure possible, explicitly excluding individual fault.
Capacity Planning
Deciding in advance how much capacity will be needed, given growth, seasonality and failure scenarios, and ensuring it can be there in time.
Chaos Engineering
Deliberately injecting failure into a system to discover, before an incident does, which of your resilience assumptions are false.
Disaster Recovery
The plan and capability for restoring service after an event that takes out a whole site, region or system.
Dropbox's Move Off S3
Dropbox moved the majority of its file storage off Amazon S3 onto custom infrastructure, reporting savings that its S-1 filing put at roughly $75 million over two years.
Error Budget
The amount of unreliability an SLO permits, treated as a resource that feature velocity spends.
Reliability vs Complexity
Mechanisms that add availability and add failure modes.
Cost vs Reliability
Each nine costing an order of magnitude, and pricing the failure instead.
Build vs Buy
Differentiation versus table stakes, priced over five years.
Build vs Buy
Differentiation, five-year TCO, and the exit cost of each option.
Centralised vs Distributed
Shared platform leverage against team autonomy.
Delivery vs Maintainability
Fast in the cheap places, careful in the expensive ones.
Functional vs Non-Functional
Behaviour versus quality of behaviour, and why only the second constrains structure.
Horizontal vs Vertical Scaling
Scale out for stateless, scale up first for stateful.
Layer 4 vs Layer 7
Connection-level versus request-level balancing, and what each unlocks.
Managed vs Self-Managed
Trading control and unit cost against operational attention.
Monolith vs Microservices
A team-topology decision far more often than a technology one.
Orchestration vs Choreography
A coordinator that knows the flow, or services that react to events.
Performance vs Cost
Buying latency, and knowing what the last millisecond is worth.
Rebuild vs Re-architect
Why greenfield replacement fails, and the narrow cases where it does not.
Reliability & Resilience
General material on designing for failure.
Reliability Culture
Blamelessness, error budget policy and reliability as a funded property.
SQL vs NoSQL
Decided by access patterns and query flexibility, not by data volume.
Security vs Usability
Varying control by the value of the action rather than uniformly.
Serverless vs Containers
Spiky and event-driven versus sustained throughput.
Single vs Multi-Region
Driven by RTO, RPO and residency rather than by ambition.
Strong vs Eventual Consistency
A per-operation decision, resolved by what a stale read would cost.
Sync vs Async
Whether the caller's outcome depends on the callee's response.
Availability Mathematics
Series dependencies multiplying, and redundancy that is not independent.
Capacity Planning
What does not autoscale, and the lead-time items that need a date.
Chaos Engineering
Hypothesis-driven failure injection with a bounded blast radius.
DR Testing
Restore drills, timed against the stated RTO, into a clean environment.
Degradation Modes
Deciding in advance what is shed first and what is protected.