Jitter / j

Jitter: cache in Miami (MIA) · J-44

xserv-j-778ce12ebadf

Runbook J-44 for Jitter in Miami (MIA). Marker xserv-j-778ce12ebadf. This page covers cache for LATAM operators, not a worldwide average.

Jitter: How XServ runs it day to day

Probes for Jitter (j-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.

Jitter: What operators should measure

Policy for Jitter is versioned as j-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.

Jitter: Failure modes we actually see

Capacity notes for j-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.

Jitter peering J-07

Peering for Jitter (j-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.

Jitter cache J-08

Cache rules for Jitter on j-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.

Jitter headers J-09

Headers for j-09 carry the letter, the region (GRU) and a request id. Jitter debugging in São Paulo should not require a packet capture in Santiago first.

Jitter timeouts J-10

Timeouts on j-10 are tighter than the WAN RTT to Bogotá. Jitter in Santiago fails fast and retries once; a third try needs a human because it is no longer a blip.

Is transit the default path?
No. Peering in Miami is default; transit to São Paulo is overflow and is billed that way.
Does Jitter on letter J share fate with other letters?
The control plane is shared. Data-plane queues for Jitter stay isolated, so incident j-01 cannot drain neighbor letters.