User Connections (MSSQL)

[thiagoftsm]

Summary

Despite collecting data from Perflib, this PR adds data collection from SQL because it appears to be more reliable when compared to other MSSQL tools.

Test Plan

1. Compile this branch and generate an installer.
2. Run it on a server running MSSQL.

Additional Information

For users: How does this change affect me?

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Summary by cubic

Add SQL-based collection for MSSQL user connections to improve reliability when Perflib is incomplete. Also adds a config flag to control this collection and updates charts to plot the metric.

• New Features
  • Collect user connections via SQL: SELECT COUNT(*) FROM sys.dm_exec_sessions WHERE is_user_process = 1.
  • New option: collect user connections (default: yes) to enable/disable this query.
  • Charts updated to plot user connections from the SQL path.
  • Docs updated to include the new option.

^{Written for commit df56ce5. Summary will update automatically on new commits.}

[cubic-dev-ai]

1 issue found across 4 files

Prompt for AI agents (all 1 issues)

Understand the root cause of the following 1 issues and fix them.


<file name="src/collectors/windows.plugin/perflib-mssql.c">

<violation number="1" location="src/collectors/windows.plugin/perflib-mssql.c:423">
Perflib user-connection collection is now gated on `collect_user_connections`, so disabling the SQL probe also disables the perflib fallback and the metric never updates.</violation>
</file>

_{Reply to cubic to teach it or ask questions. Re-run a review with @cubic-dev-ai review this PR}