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fix(suse-observability): fix freshness and concurrency monitors misfiring - #26

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230-freshness-monitor-flapping
Sep 23, 2026
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VioletCranberry merged 1 commit into
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230-freshness-monitor-flapping

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Fixes two monitors from #25 that misfire on healthy systems.

  • Freshness used the instantaneous age of the newest sample, which rises to the scrape interval between scrapes. On nightly, 2 of 10 healthy namespaces were above the 30s threshold at the time of checking. It now uses the minimum age over a minute, i.e. the scrape-to-queryable delay. Worst case over 6h across all 10 namespaces: 6s.
  • Insert/Select concurrency also matched vmagent, whose capacity is 2 on small deployments, so 2 vmagent pods were DEVIATING. Scoped to VictoriaMetrics.

Test-deployed to nightly: all three monitors CLEAR, matching only VictoriaMetrics pods including HA instance 1.

Correction to #25: its note that the counter-based monitors produce no check states came from a parsing error on my side. All six evaluate normally.

Refs https://github.com/StackVista/helm-charts-internal/issues/230

…iring

The freshness monitor compared the instantaneous age of the newest sample
against 30s. That age climbs to the scrape interval between every scrape,
so healthy namespaces crossed the threshold each cycle and flapped. Take
the minimum age over a one-minute window instead, which removes the scrape
sawtooth and leaves the scrape-to-queryable delay.

The aggregation has to sit outside the subquery; the metric backend rejects
an aggregation inside it.

Scope both concurrency monitors to VictoriaMetrics. vmagent exposes the same
vm_concurrent_insert metrics for its own incoming writes, and on small
deployments its capacity of 2 put it into DEVIATING on normal load.
@VioletCranberry
VioletCranberry merged commit db19448 into main Sep 23, 2026
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VioletCranberry deleted the 230-freshness-monitor-flapping branch September 23, 2026 11:01
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2 participants