specification: API Commons Rate Limits
specificationVersion: '0.1'
schema: https://raw.githubusercontent.com/api-evangelist/interface-research/main/schema/api-commons.yml#/$defs/RateLimits
provider: IBM MQ
providerId: ibm-mq
created: '2026-05-04'
# Provenance stamped 2026-08-11: this artifact was written by the API Evangelist
# bulk sweep dated 2026-05-04, not harvested from the provider. See roadmap#35.
method: generated
modified: '2026-05-05'
reconciled: false
tags:
  - Async
  - Enterprise
  - Integration
  - Messaging
  - Middleware
  - Queue
  - Rate Limiting
description: IBM MQ does not publish per-second HTTP rate limits in the same way as SaaS APIs; throughput
  on managed MQ on Cloud is governed by the chosen reserved-capacity tier (Small / Medium / Large) and
  the queue manager's configured maximum channels, MQI bind connections, and message size limits. On-premises
  MQ throughput is bounded by the host hardware, channel definitions (MAXMSGS, SHARECNV), and queue depth
  settings. Limits captured here describe the documented governance surfaces rather than fabricated TPS
  numbers.
notes: Specific per-second TPS numbers are workload- and tier-dependent; documented as 'varies' rather
  than guessed. The IBM MQ administration REST API does not document fixed HTTP rate-limit headers.
responseCodes:
  throttled: 429
  serviceUnavailable: 503
limits:
  - name: IBM MQ on Cloud Reserved Capacity throughput
    scope: deployment
    metric: varies
    limit: governed by Small / Medium / Large reserved-capacity tier
    applies:
      - IBM MQ REST API
      - IBM MQ Messaging REST API
      - IBM MQ JMS API
      - IBM MQ Native API
  - name: Queue manager channel limits
    scope: queue-manager
    metric: concurrent_connections
    limit: governed by queue-manager MAXCHANNELS / MAXACTIVECHANNELS / SHARECNV
    applies:
      - IBM MQ JMS API
      - IBM MQ Native API
  - name: Message size
    scope: queue
    metric: bytes_per_message
    limit: governed by queue MAXMSGL (default 4 MB, max 100 MB)
    applies:
      - IBM MQ REST API
      - IBM MQ Messaging REST API
      - IBM MQ JMS API
      - IBM MQ Native API
policies:
  - name: Backoff Strategy
    description: Clients receiving 2033 (MQRC_NO_MSG_AVAILABLE) or 2009 (MQRC_CONNECTION_BROKEN) should
      reconnect with exponential backoff; HTTP clients should honor 429 / 503 with exponential backoff
      and jitter.
  - name: Channel Heartbeats
    description: Channels use HBINT to detect inactivity; long-running consumers should tune heartbeat
      and keepalive parameters to avoid spurious disconnects under load.
  - name: Capacity Sizing
    description: For IBM MQ on Cloud, pick a Reserved Capacity tier (Small / Medium / Large) sized to
      peak throughput; tier upgrades are scheduled rather than instant.
  - name: Fair Use
    description: Even on dedicated deployments, sustained traffic that materially impacts shared infrastructure
      may be subject to operational throttling.
maintainers:
  - FN: Kin Lane
    email: kin@apievangelist.com