---
last_verified: 2026-03-14
description: |
  Real-world limits that differ from official documentation or are not
  well-documented. These come from actual deployment experience.
---

limits:
  - service: ADB-S
    limit: "Concurrent connections"
    documented: "300 per OCPU"
    real_world: |
      300 per OCPU is the hard limit, but performance degrades noticeably
      past 200 active sessions per OCPU. Size for 200 concurrent active
      sessions per OCPU, not 300.
    recommendation: "Plan for 200 active sessions per OCPU as practical limit"

  - service: ADB-S
    limit: "Auto-scaling speed"
    documented: "Automatic"
    real_world: |
      Takes 2-3 minutes to begin scaling. Not instantaneous. Very short
      bursts (< 3 minutes) may complete before scaling activates.
    recommendation: "Size base OCPUs for P75 to absorb initial burst"

  - service: ExaCS
    limit: "Provisioning time"
    documented: "Hours"
    real_world: |
      Can take 4-8 hours for infrastructure provisioning. VM cluster
      creation adds another 1-2 hours. Total: 6-10 hours first time.
    recommendation: "Plan provisioning 1-2 business days ahead"

  - service: OKE
    limit: "Node provisioning"
    documented: "Minutes"
    real_world: |
      Node provisioning: 3-5 minutes for compute instance.
      Node ready (kubelet + image pull): 5-10 minutes total.
      Pod scheduling after node ready: 10-30 seconds.
    recommendation: "Plan for 10-minute node scale-up, keep warm pool for critical workloads"

  - service: FastConnect
    limit: "Provisioning time"
    documented: "Varies by partner"
    real_world: |
      Partner-based: 2-6 weeks depending on partner and location.
      Co-location: 1-2 weeks if already in the same facility.
      Always have IPSec VPN as backup during provisioning.
    recommendation: "Start procurement 6-8 weeks early, use VPN as interim"

  - service: Block Volume
    limit: "IOPS per volume"
    documented: "Up to 25K (Balanced), 35K (Higher Performance)"
    real_world: |
      Documented limits are achievable with sufficient volume size.
      Small volumes (< 200 GB) won't reach max IOPS due to per-GB ratio.
      Need 417 GB for 25K IOPS on Balanced (60 IOPS/GB).
    recommendation: "Size volumes for IOPS requirement, not just capacity"

  - service: Object Storage
    limit: "API rate limits"
    documented: "Request-based"
    real_world: |
      Burst throttling can occur at ~1000 requests/second per bucket.
      Use multipart upload for large objects. Prefix partitioning helps
      for high-throughput scenarios.
    recommendation: "Use multipart upload, prefix partitioning for high throughput"

  - service: ADB-S
    limit: "Maximum databases per tenancy"
    documented: "Service limits page"
    real_world: |
      Default limit is often 10-20 ADB instances per region. Need to
      request limit increase via support ticket. Increases are usually
      approved within 1-2 business days.
    recommendation: "Request limit increases early in project planning"