Blocked Processes Service

Overview

The Blocked Processes Service watches the SBN database for processes that have become blocked — that is, one process waiting on another that is holding a lock it needs. On a fixed timer the service checks the database, and when it finds blocked or blocking processes it records their details (process ID, status, login, host, command, and resource usage) to its log so the situation can be reviewed.

If the same process stays blocked across repeated checks, the service sends an email alert so it can be looked into. To avoid flooding inboxes, the service only emails once a blocked process has been seen a set number of times in a row, and it keeps quiet again until the situation clears and recurs. When processes are no longer blocked, no further alerts are sent.

The service requires a working SBN data-server connection and at least one valid SMTP server for sending alerts; if either cannot be established at start-up, the service logs the reason and stops.

Service Manager

Instructions for installing and interacting with this service is found here.

Service Properties

Only properties specific to this service are listed here. Common service properties (SBN Server connection, Logging, SMTP) are found here.

Timer (In Seconds)

How often the service checks the database for blocked processes. The service waits this many seconds between cycles, then runs another check.

Count Before Emailing

How many consecutive checks a process must remain blocked before an email alert is sent. A higher value avoids alerting on brief, self-clearing blocks; a lower value alerts sooner. Once an alert is sent for a process, no further email is sent for it until the block clears and recurs.

Verbose Logging

When enabled, the service writes extra detail to its log, including a note on each cycle as it checks for blocked processes. Normally left off to keep the log concise.