Latency / l
Latency: cache in Miami (MIA) · L-08
xserv-l-6a4ed3e7ca42
Runbook L-08 for Latency in Miami (MIA). Marker xserv-l-6a4ed3e7ca42. This page covers cache for LATAM operators, not a worldwide average.
Latency: How XServ runs it day to day
Probes for Latency (l-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.
Latency: What operators should measure
Policy for Latency is versioned as l-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.
Latency: Failure modes we actually see
Capacity notes for l-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.
Latency rollback L-06
Rollback for l-06 is a documented command, not a hope. Transit is billed as backup while Latency prefers peering in Santiago. If cost spikes, the runbook cuts overflow to Bogotá before touching customer prefixes.
Latency peering L-07
Peering for Latency (l-07) prefers the IX fabric that already carries last-mile ISPs in Bogotá. Session counts and prefix limits are on the same page as the Miami backup path.
Latency cache L-08
Cache rules for Latency on l-08 keep language-correct objects near Miami. São Paulo is a sibling cache, not an origin. TTLs are short enough that a bad asset does not live through a weekend.
Latency headers L-09
Headers for l-09 carry the letter, the region (GRU) and a request id. Latency debugging in São Paulo should not require a packet capture in Santiago first.
- Is transit the default path?
- No. Peering in Miami is default; transit to São Paulo is overflow and is billed that way.
- Does Latency on letter L share fate with other letters?
- The control plane is shared. Data-plane queues for Latency stay isolated, so incident l-01 cannot drain neighbor letters.