subscription_health
Read-only
Analyze subscription feed sequences to detect dropped, duplicate, or out-of-order data and identify republish rejections and overloaded channels causing OPC-UA/Sparkplug data loss.
Instructions
[READ][risk=low] Health of a sequenced subscription feed (OPC-UA or Sparkplug B).
Detects dropped notifications (sequence gaps), duplicates / out-of-order, a high
republish-rejection rate, and overloaded channels — the classic Kepware
"too many tags on one channel → republish/queue-flush dropouts" fault.
Args:
sequence: Sequence numbers actually received, in arrival order.
republish_requested: How many republish requests were made.
republish_rejected: How many were rejected (server couldn't keep up).
tags_per_channel: {channel/endpoint: tag_count} — flags channels over the max.
max_tags_per_channel: Density above which a channel is flagged (default 5000).
wrap_at: Modulus for rolling counters (e.g. 256 for Sparkplug B seq); omit
for monotonic OPC-UA counters.
Returns dict: {received, missed_count, duplicate_count, out_of_order_count,
republish_requested, republish_rejected, republish_reject_rate,
overloaded_channels:[{channel, tags}], max_tags_per_channel,
verdict ('ok'|'reordered'|'lossy'|'overloaded'), recommendation}.
Example: subscription_health(sequence=[1,2,4,5], tags_per_channel={"ch1":7000}).
Input Schema
TableJSON Schema
| Name | Required | Description | Default |
|---|---|---|---|
| wrap_at | No | ||
| sequence | Yes | ||
| tags_per_channel | No | ||
| republish_rejected | No | ||
| republish_requested | No | ||
| max_tags_per_channel | No |