The incident was caused by sustained and severe latency in Service-A, the upstream dependency for Service-B, resulting in repeated `UpstreamSlowResponse` warnings on `service-b-02` with P99 latencies reaching 16000ms (ctx://meridian/splunk-events/evt_f444afb2db7504c9).
Investigated in 6.0s·22 artifacts read·6 entities traversed
Impact
summarizing business impact…
Severity
critical
Events in chain
8
Window
2s
from 20:46:23
Entities affected
5
I·1 · B·4 · C·0
Actions
2
1 high / crit
Root cause hypothesis
agent-meridian-reasoner
The incident was caused by sustained and severe latency in Service-A, the upstream dependency for Service-B, resulting in repeated `UpstreamSlowResponse` warnings on `service-b-02` with P99 latencies reaching 16000ms (ctx://meridian/splunk-events/evt_f444afb2db7504c9). The causal chain confirms this was a continuous series of identical degradation events starting with ctx://meridian/splunk-events/evt_de82576532363e4a.
Causal chain · 8 events
ordered by USC temporal
20:46:23 UTC
webapp:error on service-b-02: {"level":"WARN","service":"service-b","upstream":"service-a","error_t…
ctx://meridian/splunk-events/evt_de82576532363e4a
20:46:23 UTC
webapp:error on service-b-02: {"level":"WARN","service":"service-b","upstream":"service-a","error_t…
ctx://meridian/splunk-events/evt_fee518403753fb1b
20:46:23 UTC
webapp:error on service-b-02: {"level":"WARN","service":"service-b","upstream":"service-a","error_t…
ctx://meridian/splunk-events/evt_70450d7e41b2ad70
20:46:23 UTC
webapp:error on service-b-02: {"level":"WARN","service":"service-b","upstream":"service-a","error_t…
ctx://meridian/splunk-events/evt_3648252a4d419b5e
20:46:23 UTC
webapp:error on service-b-02: {"level":"WARN","service":"service-b","upstream":"service-a","error_t…
ctx://meridian/splunk-events/evt_e6d60e22a2b83dd3
20:46:24 UTC
webapp:error on service-b-02: {"level":"WARN","service":"service-b","upstream":"service-a","error_t…
ctx://meridian/splunk-events/evt_5b9f2eaaa5e6cf22
20:46:24 UTC
webapp:error on service-b-02: {"level":"WARN","service":"service-b","upstream":"service-a","error_t…
ctx://meridian/splunk-events/evt_8db4934a15b34927
20:46:24 UTC
webapp:error on service-b-02: {"level":"WARN","service":"service-b","upstream":"service-a","error_t…
01criticalImmediately investigate the root cause of the 16000ms P99 response time in the upstream Service-A, as reported by Service-B on `service-b-02` (ctx://meridian/splunk-events/evt_f444afb2db7504c9).
02mediumReview Service-B's logging thresholds for `UpstreamSlowResponse` given the rapid succession of warnings identified in the causal chain (ctx://meridian/splunk-events/evt_de82576532363e4a to ctx://meridian/splunk-events/evt_f444afb2db7504c9).