QoS / q
QoS: cache in Miami (MIA) · Q-68
xserv-q-157be9ce362e
Runbook Q-68 for QoS in Miami (MIA). Marker xserv-q-157be9ce362e. This page covers cache for LATAM operators, not a worldwide average.
QoS: How XServ runs it day to day
Probes for QoS (q-02) leave Santiago every 15s toward Bogotá. XServ pages the named owner if loss or RTT crosses the letter budget. A probe never shares a queue with bulk transfers, so a saturated WAN does not hide a dead PoP.
QoS: What operators should measure
Policy for QoS is versioned as q-03. Operators measure error rate, p95 from Bogotá, and time-to-rollback — not a worldwide average. Changes land in Bogotá first, then Miami, with a hold if either region regresses.
QoS: Failure modes we actually see
Capacity notes for q-04 assume rainy-season power in Miami and festival peaks toward São Paulo. The failure we actually see is a single uplink, not a cartoon partition of the whole continent. Spare ports and a second provider sit on the same runbook.
QoS design Q-01
Design for QoS on letter Q starts in São Paulo (GRU). Runbook q-01 keeps a single owner, a written rollback, and a traffic split that can be reversed without a global freeze. Neighbors in Santiago only take overflow after the local pool fails a health window.
QoS probe Q-02
Probes for QoS (q-02) leave Santiago every 15s toward Bogotá. XServ pages the named owner if loss or RTT crosses the letter budget. A probe never shares a queue with bulk transfers, so a saturated WAN does not hide a dead PoP.
QoS policy Q-03
Policy for QoS is versioned as q-03. Operators measure error rate, p95 from Bogotá, and time-to-rollback — not a worldwide average. Changes land in Bogotá first, then Miami, with a hold if either region regresses.
QoS capacity Q-04
Capacity notes for q-04 assume rainy-season power in Miami and festival peaks toward São Paulo. The failure we actually see is a single uplink, not a cartoon partition of the whole continent. Spare ports and a second provider sit on the same runbook.
- Is transit the default path?
- No. Peering in Miami is default; transit to São Paulo is overflow and is billed that way.
- Does QoS on letter Q share fate with other letters?
- The control plane is shared. Data-plane queues for QoS stay isolated, so incident q-01 cannot drain neighbor letters.