Je, ungalikaje kubuni ufuatiliaji wa programu kutoka mwanzo?

Question

Accepted Answer

Anza **kutoka juu kwenda chini kutoka kile watumiaji huwisi**, si kutoka chini kwenda juu kutoka kwa miundombinu. Kundi la watumiaji halisi linaliloaminika zaidi haliena thamani ikiwa ombi limeshindwa, kwa hiyo anza na **SLI** inayokabili watumiaji — **uchelezi**, **kiwango cha makosa**, **upatikanaji** — kisha ongeza ishara nne za dhahabu, kisha vipimo vya miundombinu mwisho.

## Kumlazo, kutoka kwa mtumiaji ndani

```text
1. USER-FACING SLIs   → what the user experiences (latency, errors, availability)
2. GOLDEN SIGNALS     → latency, traffic, errors, saturation per service
3. INFRA METRICS      → CPU, memory, disk, network (causes, not symptoms)
```

Kama tu kuiga CPU na disk (kutoka chini kwenda juu), unaweza kuwa kijani kikamilifu wakati watumiaji wanapokea 500s. Kuiga SLI kwanza (kutoka juu kwenda chini) inamaanisha unatahadharisha juu ya **dalili watumiaji kweli huwisi**, kisha unachimba ndani ya ishara za dhahabu na miundombinu kupata sababu.

## Bomba: chomeza → kusanya → paneli → tahadhari

```text
INSTRUMENT  app emits metrics/logs/traces (e.g. request_duration_seconds histogram)
   ↓
COLLECT     a TSDB scrapes/ingests them (Prometheus, Datadog agent)
   ↓
DASHBOARD   visualize SLIs + golden signals (Grafana) for humans to read
   ↓
ALERT       fire on SLO violations / burn rate, routed to on-call
```

## Hatua ya kuanza ya konkreeti

```promql
# Availability SLI: fraction of requests that succeed
sum(rate(http_requests_total{status!~"5.."}[5m]))
  / sum(rate(http_requests_total[5m]))

# Latency SLI: p99 request latency
histogram_quantile(0.99, sum by (le) (rate(http_request_duration_seconds_bucket[5m])))
```

Fafanua **SLO** kwa kila SLI (k.m. 99.9% upatikanaji, p99 < 300ms), ubao hao, na tahadhari wakati SLO iko hatarini — si kila kusikitisha kidogo.

## Kwa nini inamaanisha

Ufuatiliaji uliojengwa kutoka chini kwenda juu unakuambia disk ni 80% kamili lakini si kwamba wateja hawezi kutoka. Kuanza na SLI inayokabili watumiaji huambia kila paneli na tahadhari nyuma kwa athari halisi ya mtumiaji, hunabaki kelele chini, na inatoa njia wazi ya kuchimba (dalili → ishara ya dhahabu → sababu ya miundombinu) wakati kitu kikabaya.