“SQL Server Is Slow” - Part 2 of 4

The 10-Minute Outside-In Triage

Author

Kevin Hill
September 12, 2025

Cup 3 of ? starting as I write this post…

Don’t Blame SQL First

It’s 9:05 AM and your helpdesk lights up: “The SQL Server is down. Nothing works.”

By 9:07, everyone is staring at you.

The trap: you open SSMS and start digging for blocking queries. But what if the database isn’t the problem at all?

I’ve seen teams lose hours chasing SQL when the real culprit was a Windows power plan, an antivirus update, or a snapshot on the storage array.

That’s why step two in our framework is a 10-minute outside-in triage. You prove or eliminate the usual suspects before you go digging inside SQL Server.

The Outside-In Checklist

When an incident is happening right now, you don’t need deep analysis. You need to rule out the obvious and collect proof.

Step 1: Blast Radius (1 min)

  • Are other apps/servers slow too?

  • Other users, or just one?

  • Cloud? Check provider status pages and throttling alerts.
    If everything is slow, SQL may not be the root cause.

Step 2: Host & OS Health (3 - 4 min)

  • CPU: Is the server pegged, not just sqlservr.exe?

    • I have a story here...coined the term “three finger salute” from it (CTRL-ALT-DELETE). Ask me if we ever meet in person!

  • Hypervisor: Look for VM “ready time” or “steal time.”

  • Power plan: Make sure Windows is on High Performance.

  • Memory: Check paging, commit vs installed.

  • Antivirus: Any active scans?

  • Windows Update: Patches or Defender scans running?

Step 3: Storage Sanity (3 - 4 min)

  • Latency: Are read/write times spiking?

  • Queue depth: Backlog on MDF, LDF, or tempdb volumes?

  • Snapshots/backup agents: Running now?

  • Cloud disks: Bursting credits exhausted?

Step 4: Network Checks (1 - 2 min)

  • Is RDP sluggish? File copies slow?

  • Any new firewall/VPN/SSL changes?

Step 5: Quick SQL Health Pulse (1 - 2 min)

(You’re not tuning queries here, you’re checking basic health)

  • Blocking chains: is one session holding everyone else hostage? Sp_whoisactive is great for this!

  • Current waits: PAGEIOLATCH (storage), WRITELOG (log), ASYNC_NETWORK_IO (client/network). Use SQLSkills Waits Now script

  • Active jobs: backups, CHECKDB, index maintenance colliding with business hours.

The Bottom Line

The point of a 10-minute triage isn’t to fix everything. It’s to prove or eliminate SQL Server as the culprit.

When you walk into a war room and say, “Here’s proof it’s the storage snapshot, not SQL,” you stop the blame game cold.

At Dallas DBAs, we use this exact checklist when clients call in a panic. It’s fast, repeatable, and it keeps you from chasing the wrong rabbit.

First Month Free for New Pocket DBA® Clients

SQL tidBITs:

If your SQL Server is virtualized, learn to read CPU Ready/Steal Time. SQL may show 20% CPU, but if the hypervisor is starving your VM, users will still feel like the server is on dial-up.

🔒 Security Advisories
Microsoft’s September 2025 Patch Tuesday Fixes for SQL Server & More — Patch available; includes fixes for CVE-2024-21907 (Newtonsoft.Json) and other SQL Server / Windows vulnerabilities. (BleepingComputer)


Security Update for SQL Server 2016 SP3 (KB5065226) — Patch available; resolves information disclosure & elevation-of-privilege CVEs in SQL Server 2016.

Samsung launches Galaxy S25 FE & the Tab S11 series — New premium-lite phone/tablet hardware. (The Times of India)

Consumer prices rose at annual rate of 2.9% in August, as weekly jobless claims jump - which causes Fed things, which causes interest rate guesses, which affects housing and cars, and the domino effect keeps on rolling.

Slow week 😊

Please share with your friend that doesn’t know anything about Task Manager

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