Use the Blocking Processes alert in Mini DBA to monitor SQL Server instances and make this condition visible before it becomes a wider database incident.
Mini DBA describes this alert as: Processes blocking other processes Only head blockers (not blocked by any other processes) are counted A degree of this is to be expected in busy environments as locks are taken out on objects The MaxThreshold represents the number of blocking processes that it takes to trigger an alert The default evaluation frequency is Minute, so the alert is intended to be close enough to operational reality for live triage.
This alert highlights concurrency pressure. Blocking, long sessions, and lock waits can turn a healthy server into a slow user experience, so the alert gives administrators an early route to the sessions, statements, and applications involved.
Enable it on any monitored SQL Server instance where this condition would require an administrator to investigate or communicate with the application team. Tune noisy development systems after you have a short baseline.
Threshold meaning: Blocking spid. Major threshold: 5 sessions. Minor threshold: 0 sessions. Comparison direction: "over". Use higher thresholds on batch-heavy, development, or intentionally bursty systems where brief pressure is expected. Use lower thresholds on latency-sensitive production systems, small instances with little headroom, and services with strict recovery or availability commitments.
Open the activity, blocking, and query views to identify the lead blocker, SQL text, wait type, login, host, and application. Prefer fixing the query or transaction pattern, but kill or cancel the blocking session when the business impact is higher than the rollback risk.
If the alert creates repeated noise, review whether it is enabled on the correct instances, whether maintenance windows are configured, and whether the minor and major routes match the real business impact. Keep enough history to prove the new setting before changing it broadly.