Knowledge GraphOperational Concerns

Realm

Operational Concerns

Correctness, delivery, persistence, recovery, consistency, coordination, and reliability.

Entries

ACID

ACID is a transaction contract: atomicity, consistency, isolation, and durability.

Acknowledgments

Acknowledgments answer: what does a participant or substrate claim has happened?

Admission Control and Load Shedding

Admission control decides whether, when, and under which conditions work may enter a bounded system, service, queue, resource, process, or authority scope. Load shedding deliberately refuses, drops, cancels, expires, samples, redirects, or degrades selected work when serving everything would violate more important service or progress constraints.

Arbitration

Arbitration resolves local contention among competing eligible occurrences when the system must select, admit, order, or grant one or more of them.

CAP Theorem

The CAP theorem describes an impossibility for distributed shared data under network partition: a system cannot simultaneously guarantee linearizable consistency, availability, and partition tolerance for all executions.

Commit Boundaries

Commit Boundaries answer: what becomes accepted as one unit, and within which boundary?

Compatibility and Evolution

Compatibility and evolution describe whether independently versioned producers, consumers, stored histories, schemas, definitions, and realizations can continue to correspond without changing the intended meaning.

Concurrency Control

Concurrency Control answers: How can multiple concurrent histories be reconciled into a single valid history?

Consensus

Consensus answers: how do multiple observers agree on one value despite concurrency, delay, partial failure, or independent local views?

Consistency Models

Consistency Models constrain which observations are valid for a set of events, transitions, versions, sessions, replicas, and ordering relations.

Consistent Cuts

A consistent cut is a selected set of events, versions, observations, or process positions that is closed under the declared causal prerequisites.

Consumer Coordination

Consumer coordination describes how eligible observers discover, claim, receive, schedule, and complete work made available through an interaction channel.

Coordination

Coordination answers: how is multi-step or multi-participant work made coherent across observers?

Correlation and Conversations

Correlation and conversations describe how independently occurring messages, requests, replies, observations, attempts, and process steps are recognized as participating in one interaction or longer-lived protocol.

CRDTs

CRDTs, conflict-free replicated data types, are replicated data types designed so that independently updated replicas converge without requiring synchronous coordination for every update.

Deadlock and Livelock

Deadlock and livelock are failures of liveness in which enabled or accepted work does not reach its declared completion boundary.

Delivery Progress and Settlement

Delivery progress and settlement describe what input an application has durably accounted for and how that durable fact authorizes a later change to provider-managed delivery state.

Delivery Semantics

Delivery Semantics answers: what guarantees does an interaction edge provide?

Distributed Failure Scenarios

Distributed failure scenarios are recurring hazard shapes that appear when effects, observations, commit boundaries, durability, isolation, coordination, and recovery cross independently governed boundaries.

Dual-Write Problem

The dual-write problem is the failure mode that appears when one operation tries to commit two or more effects across independent commit boundaries without one atomic commit protocol or durable recovery protocol connecting them.

Durability

Durability answers: which facts, histories, effects, decisions, or execution material survive which failures?

Failure Models

Failure models state which faults, delays, losses, corruptions, recoveries, and correlated disruptions a system or protocol admits when making a correctness or progress claim.

Fairness

Fairness constrains complete executions so that eligible participants, messages, or actions are not postponed forever under the stated assumptions.

Flow Control

Flow control regulates how much work may be admitted or remain in flight between participants in response to available capacity.

Idempotency

Idempotency is the property that repeated handling of the same semantic input does not produce duplicate domain effects.

Interaction Control Flow

Interaction control flow identifies which participant or mediating locus actively drives each operation at a distributed interaction boundary.

Isolation

Isolation describes what concurrent operations are allowed to observe of one another while they execute.

Linearization Points

A linearization point is the logical instant at which an operation takes effect in the abstract sequential history used to justify linearizability. It must lie between that operation's invocation and response.

Load Balancing

Load balancing governs how admitted work is distributed among eligible capacity-bearing destinations at a declared boundary so that service, capacity, fairness, locality, and failure objectives can be met.

Locality

Locality is an operational property of the relationship between a workload and its dependencies. It describes how placement and reuse affect the cost of accessing, moving, or reconstructing those dependencies.

Metastability

Metastability is the operational condition in which a system enters a locally persistent, usually degraded operating regime that continues after the disturbance that triggered it has disappeared.

Observability and Provenance

Observability and provenance describe the evidence by which observers can inspect, explain, correlate, and diagnose system behavior across boundaries and time.

Operational Control

Operational control describes authorized interventions that inspect or change how a running system admits, routes, schedules, pauses, drains, replays, quarantines, purges, resumes, or tests work.

Ordering

Ordering defines the scope within which events, commands, observations, or effects are sequenced.

Parallelism

Parallelism describes overlapping execution of work on distinct execution resources at a declared boundary.

Partitioning

Partitioning governs how a population of subjects, data, or work is divided into assignment scopes at a declared boundary, and how the assignment behaves as the population, partition set, or rule changes.

Persistence

Persistence answers: what is recorded as authoritative material?

Progress Conditions

Progress Conditions classify liveness guarantees for concurrent or distributed operations.

Rate Limiting

Rate Limiting constrains how quickly work may be accepted, dispatched, delivered, or processed.

Reconstitution

Reconstitution answers: how is usable state recovered?

Recovery

Recovery defines how a system returns to coherent operation after failure, interruption, conflict, timeout, overload, or partial progress.

Retention, Expiration, and Quarantine

Retention, expiration, and quarantine describe how long interaction material remains available, when it ceases to be admissible for ordinary processing, and how exceptional material is isolated for inspection, repair, replay, reconciliation, or disposal.