Repository navigation
Observability for views (V19) #331
Description
Part of epic #305.
Problem. No per-KG or per-view metrics; SubscriptionMetrics not exported; /metrics walks every KG under the storage lock (src/protocol/rest/handlers/admin.rs:93-158; src/protocol/subscription/mod.rs:72-78); #300 covers general gaps.
Target. /metrics/prometheus with kg/view labels: committed revision vs frontier (lag revisions, ms), maintenance time per commit histogram, arrangement bytes and rows per view, generation builds, subscribers per view, deltas delivered, delivery lag, view_reads, rule_evaluations, index epochs; tracing view_generation_built, view_over_budget, maintainer_lag; scrape without the storage write-preferring lock.
Acceptance. Metrics present and documented in guides/rest-api.mdx; the perf gate reads them for B6-B9; #300's export of subscription metrics closed by this PR.
Size S. Dependencies V10. Order slot 9.
Activity
jsam commentedon Oct 10, 2026
View observability (lag, maintenance histogram, rows and bytes, generation and subscriber metrics) landed in https://github.com/inputlayer/inputlayer-symbolic/pull/75. The view_reads and rule_evaluations metrics still lack kg/view labels. Remaining work continues in https://github.com/inputlayer/inputlayer-symbolic/issues/122.