🔐 Security Data Filter Performance Analysis Tool

[Vaishnavi Lathk]

📖 Overview

Security Data Filters (SDFs) are integral to enforcing data access controls and compliance rules in ServiceNow. These filters define what data a user can see based on roles, conditions, or business logic.

However, as filters grow in complexity, they can lead to significant performance degradation—especially when applied to large datasets or high-traffic tables like task, incident, or cmdb_ci.

To proactively address this, ServiceNow provides a Security Data Filter Performance Analysis Tool. This diagnostic utility helps evaluate the real-world performance impact of any security data filter, enabling you to make informed decisions that balance security with system performance.

🎯 Key Use Case

Why use the Performance Analysis Tool?
If you're seeing slow page loads, sluggish list views, or delayed reporting, your security data filters might be the culprit. This tool helps identify how much a filter contributes to query slowness—before or after it goes live.

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🛡️ Prerequisites

Requirement	Details
🔐 Role Required	security_admin
⚙️ System Property	Must enable: glide.security.data_filter.diagnostic_enabled = true

📌 To verify or enable the property:

1. Go to sys_properties.list

2. Search for glide.security.data_filter.diagnostic_enabled

3. If it does not exist, [Add a new system property]

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🧭 Step-by-Step: Run a Security Filter Performance Analysis

Step 1: Navigate to the Data Filter

📍 Go to:
All > System Security > Security Data Filters

🔍 Select the filter you want to analyze.

✅ Tip: Target filters applied to heavily used tables or those recently modified.

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Step 2: Start Performance Analysis

Under Related Links, click:
🔍 Analyze Performance

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Step 3: Fill Out the Analyze Form

You'll see a form similar to this:

Field	Description
🔘 Data Filter	Auto-filled with the selected filter
📄 Related Active Filters	See how many other filters are affecting the table
📊 Table	Choose the table (e.g., incident)
🔍 Encoded Query (Optional)	Use actual filter logic from a list/report view
🔁 Query Runs	Enter between 10–100 for reliable metrics (recommended: 30–50)

🧠 Encoded Query Example:
priority=1^state!=6 (to simulate active high-priority incidents)

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Step 4: Run the Analysis

Click Analyze Query Performance

⏳ The system runs the query multiple times, with and without the selected filter, then summarizes the results.

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📈 Understanding the Results

Once analysis is complete, scroll to the Performance Summary section. You’ll see key metrics like:

• 🔺 Max / Min / Median / Mean query execution times

• 📉 Comparative performance with vs. without filter

• 🔦 Performance Impact Indicator (Low, Medium, Critical)

💡 Example Output:

Metric	Without Filter	With Filter	Change
Median	42 ms	58 ms	+38%
Mean	45 ms	62 ms	+37%
Max	85 ms	121 ms	+42%

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🚦 Performance Impact Levels

Indicator	Message	Explanation
🟢 Low	Filter has no impact	0% change in median execution time
🟠 Medium	Noticeable slowdown	0–100% increase in median time
🔴 Critical	Major performance hit	>100% increase in median execution time

📌 Critical filters should be redesigned or used conditionally.
E.g., try limiting scope, using indexed fields, or restructuring conditions.

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🛠️ Pro Tips for Optimization

Action	Benefit
✅ Use indexed fields in filter conditions	Faster evaluations
✅ Limit use of OR conditions	Reduces processing complexity
✅ Use dot-walking sparingly	Can lead to costly joins
✅ Evaluate filters on report-heavy tables	Prevents UI slowness for end users

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📌 Common Scenarios Where This Tool Helps

• ✅ Before deploying a new security rule

• ✅ When end users report slow list loads

• ✅ During performance audits or major upgrades

• ✅ To justify filter redesign with data

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📚 Additional Resources

• Security Data Filters Documentation

• How to Add a System Property

• Query Performance Best Practices

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✅ Summary

The Security Data Filter Performance Analysis Tool empowers ServiceNow platform admins to:

• Diagnose real-time performance impact of access controls

• Make data-informed decisions when building filters

• Improve platform speed and responsiveness

• Maintain compliance without sacrificing performance.

[Rampriya-S]

Thanks for sharing this comprehensive guide @Vaishnavi Lathk ! The clear steps, impact indicators, and optimization tips make it an invaluable reference for improving SDF performance.

[sumitp2124]

Thanks for sharing the useful ticks as it helps to reduce system loading problem . I have question on this .. is this property is active in current Yokohama release or it can work in previous release also .