question ATF Tests Running Extremely Slow After Zurich Upgrade in ITSM forum

ATF Tests Running Extremely Slow After Zurich Upgrade

Khalid9030 — Tue, 21 Oct 2025 07:34:04 GMT

Hi everyone,

After upgrading our instance to the Zurich release, we’ve noticed a significant slowdown in Automated Test Framework (ATF) execution.

Tests that used to complete in 3–4 minutes are now taking over 10 minutes, and the system often becomes unresponsive, causing all tests to fail without completing successfully.

Has anyone else experienced similar performance issues with ATF after upgrading to Zurich?
If you’ve come across this kind of issue or found any workarounds or optimizations, please let me know — it would be really helpful.

Thanks in advance!

Re: ATF Tests Running Extremely Slow After Zurich Upgrade

Bhuvan — Tue, 21 Oct 2025 08:37:40 GMT

@Khalid9030

Follow below documentation to optimize ATF Performance

https://www.servicenow.com/docs/bundle/zurich-application-development/page/administer/auto-test-framework/concept/atf-optimize-perf.html

If this helped to answer your query, please mark it helpful & accept the solution.

Thanks,

Bhuvan

Re: ATF Tests Running Extremely Slow After Zurich Upgrade

Me Being Mustaq — Tue, 21 Oct 2025 11:46:55 GMT

Assalamualaikum @Khalid9030 ,

Yes, several ServiceNow Zurich users have reported slower Automated Test Framework (ATF) execution and test suite instability since upgrading. While it’s not officially classified as a widespread regression yet, both the community and ServiceNow documentation highlight contributing factors and possible optimizations.

Identified Causes in Zurich

Regression in ATF Parallel Execution Mode
Many users observed that test suites running multiple tests concurrently (especially UI Steps) now experience delayed start times or resource locking. This is linked to changes in ATF’s internal job scheduling introduced in Zurich.
Client‑side “Waiting for page to be calm” Delays
Zurich enforces stricter client rendering validation, increasing the “page settle” timeout (up to 60 seconds) for UI‑based tests. This is meant to improve reliability but causes longer test durations.
Debug Mode and Logging Overhead
If “Enable additional debugging functionality for tests” is checked under Automated Test Framework → Properties, ATF consumes far more memory, causing lag or node unresponsiveness during long executions.
Increased Snapshot Captures and Step Replays
Zurich enables more detailed diagnostic snapshots by default (for Failure Insights), adding overhead to each step. Turning off step‑by‑step screenshots significantly improves performance.
Platform Performance Analyzer Instrumentation
The Zurich update introduced deeper instrumentation for form and UI rendering, which can conflict with ATF runs. Disabling the Performance Analyzer when running large suites helps avoid slowdowns.

Recommended Workarounds

Disable ATF Debugging and excessive screenshots
Navigate to:
Automated Test Framework → Administration → Properties
- Uncheck “Enable additional debugging functionality.”
- Set “Step screenshot frequency” to On Failure Only.
Clear Instance Cache and Restart Test Runner
Use cache.do to clear old ATF metadata, especially after an upgrade.
Reduce Test Concurrency
Run tests sequentially (single thread) or in smaller suites. Parallel execution currently exacerbates Zurich’s ATF performance bottleneck.
Monitor Using Performance Analyzer
Use the new Performance Analyzer (Zurich feature) to inspect which scripts or custom widgets are inflating ATF step times.
Apply Known Fixes / Patches
ServiceNow engineering is actively addressing ATF slowness under Problem Record PRB1633297 (internal reference). Subscribe through HI Support for targeted hotfixes in post‑Zurich patches.

In short: The slowdown originates from Zurich’s enhanced diagnostics (ATF Failure Insight and UI synchronization logic). By disabling debug features, limiting concurrency, and turning off non‑essential logging, you can restore near‑pre‑upgrade ATF speeds while staying within supported configurations.

you may find below thread helpful:

https://www.servicenow.com/community/developer-forum/atf-tests-are-very-slow/m-p/3316730
https://www.servicenow.com/community/servicenow-ai-platform-forum/atf-script-failure-in-zurich/m-p/3402398
https://www.servicenow.com/community/developer-forum/atf-execution-getting-stuck-while-executing-single-test-or-test/m-p/1981340

If it is helpful, please hit the thumbs button and accept the correct solution by referring to this solution in the future it will be helpful to them.

Thanks & Regards,

Mohammed Mustaq Shaik

Re: ATF Tests Running Extremely Slow After Zurich Upgrade

Trish Mac — Mon, 15 Dec 2025 20:01:15 GMT

Thank you very much for this. I have been banging my head against the wall with ATF tests that take a ridiculous 10 minutes or longer for a simple test. Your suggestions have me running at just under or a little over a minute per test now.

Regards,

Trish

Re: ATF Tests Running Extremely Slow After Zurich Upgrade

Me Being Mustaq — Tue, 16 Dec 2025 04:31:58 GMT

Hi @Trish Mac ,

I’m really glad to hear that the suggestions helped bring your ATF test runtimes down so significantly. It’s great to see the improvements making your work smoother and faster. Always happy to collaborate and share ideas — feel free to reach out anytime.

If it is helpful, please hit the thumbs button.

Thanks & Regards,

Mohammed Mustaq Shaik

question ATF Tests Running Extremely Slow After Zurich Upgrade in ITSM forum

ATF Tests Running Extremely Slow After Zurich Upgrade

Re: ATF Tests Running Extremely Slow After Zurich Upgrade

Re: ATF Tests Running Extremely Slow After Zurich Upgrade

Assalamualaikum @Khalid9030 ,

Identified Causes in Zurich

Regression in ATF Parallel Execution Mode
Many users observed that test suites running multiple tests concurrently (especially UI Steps) now experience delayed start times or resource locking. This is linked to changes in ATF’s internal job scheduling introduced in Zurich.

Client‑side “Waiting for page to be calm” Delays
Zurich enforces stricter client rendering validation, increasing the “page settle” timeout (up to 60 seconds) for UI‑based tests. This is meant to improve reliability but causes longer test durations.

Debug Mode and Logging Overhead
If “Enable additional debugging functionality for tests” is checked under Automated Test Framework → Properties, ATF consumes far more memory, causing lag or node unresponsiveness during long executions.

Increased Snapshot Captures and Step Replays
Zurich enables more detailed diagnostic snapshots by default (for Failure Insights), adding overhead to each step. Turning off step‑by‑step screenshots significantly improves performance.

Platform Performance Analyzer Instrumentation
The Zurich update introduced deeper instrumentation for form and UI rendering, which can conflict with ATF runs. Disabling the Performance Analyzer when running large suites helps avoid slowdowns.

Recommended Workarounds

Disable ATF Debugging and excessive screenshots
Navigate to:
Automated Test Framework → Administration → Properties

Uncheck “Enable additional debugging functionality.”

Set “Step screenshot frequency” to On Failure Only.

Clear Instance Cache and Restart Test Runner
Use cache.do to clear old ATF metadata, especially after an upgrade.

Reduce Test Concurrency
Run tests sequentially (single thread) or in smaller suites. Parallel execution currently exacerbates Zurich’s ATF performance bottleneck.

Monitor Using Performance Analyzer
Use the new Performance Analyzer (Zurich feature) to inspect which scripts or custom widgets are inflating ATF step times.

Apply Known Fixes / Patches
ServiceNow engineering is actively addressing ATF slowness under Problem Record PRB1633297 (internal reference). Subscribe through HI Support for targeted hotfixes in post‑Zurich patches.

you may find below thread helpful:

Re: ATF Tests Running Extremely Slow After Zurich Upgrade

Re: ATF Tests Running Extremely Slow After Zurich Upgrade

question ATF Tests Running Extremely Slow After Zurich Upgrade in ITSM forum

ATF Tests Running Extremely Slow After Zurich Upgrade

Re: ATF Tests Running Extremely Slow After Zurich Upgrade

Re: ATF Tests Running Extremely Slow After Zurich Upgrade

Assalamualaikum @Khalid9030 ,

Identified Causes in Zurich

Regression in ATF Parallel Execution ModeMany users observed that test suites running multiple tests concurrently (especially UI Steps) now experience delayed start times or resource locking. This is linked to changes in ATF’s internal job scheduling introduced in Zurich.​

Client‑side “Waiting for page to be calm” DelaysZurich enforces stricter client rendering validation, increasing the “page settle” timeout (up to 60 seconds) for UI‑based tests. This is meant to improve reliability but causes longer test durations.​

Debug Mode and Logging OverheadIf “Enable additional debugging functionality for tests” is checked under Automated Test Framework → Properties, ATF consumes far more memory, causing lag or node unresponsiveness during long executions.​

Increased Snapshot Captures and Step ReplaysZurich enables more detailed diagnostic snapshots by default (for Failure Insights), adding overhead to each step. Turning off step‑by‑step screenshots significantly improves performance.​

Platform Performance Analyzer InstrumentationThe Zurich update introduced deeper instrumentation for form and UI rendering, which can conflict with ATF runs. Disabling the Performance Analyzer when running large suites helps avoid slowdowns.​

Recommended Workarounds

Disable ATF Debugging and excessive screenshotsNavigate to:Automated Test Framework → Administration → Properties

Uncheck “Enable additional debugging functionality.”

Set “Step screenshot frequency” to On Failure Only.

Clear Instance Cache and Restart Test RunnerUse cache.do to clear old ATF metadata, especially after an upgrade.​

Reduce Test ConcurrencyRun tests sequentially (single thread) or in smaller suites. Parallel execution currently exacerbates Zurich’s ATF performance bottleneck.​

Monitor Using Performance AnalyzerUse the new Performance Analyzer (Zurich feature) to inspect which scripts or custom widgets are inflating ATF step times.​

Apply Known Fixes / PatchesServiceNow engineering is actively addressing ATF slowness under Problem Record PRB1633297 (internal reference). Subscribe through HI Support for targeted hotfixes in post‑Zurich patches.

you may find below thread helpful:

Re: ATF Tests Running Extremely Slow After Zurich Upgrade

Re: ATF Tests Running Extremely Slow After Zurich Upgrade

Regression in ATF Parallel Execution Mode
Many users observed that test suites running multiple tests concurrently (especially UI Steps) now experience delayed start times or resource locking. This is linked to changes in ATF’s internal job scheduling introduced in Zurich.

Client‑side “Waiting for page to be calm” Delays
Zurich enforces stricter client rendering validation, increasing the “page settle” timeout (up to 60 seconds) for UI‑based tests. This is meant to improve reliability but causes longer test durations.

Debug Mode and Logging Overhead
If “Enable additional debugging functionality for tests” is checked under Automated Test Framework → Properties, ATF consumes far more memory, causing lag or node unresponsiveness during long executions.

Increased Snapshot Captures and Step Replays
Zurich enables more detailed diagnostic snapshots by default (for Failure Insights), adding overhead to each step. Turning off step‑by‑step screenshots significantly improves performance.

Platform Performance Analyzer Instrumentation
The Zurich update introduced deeper instrumentation for form and UI rendering, which can conflict with ATF runs. Disabling the Performance Analyzer when running large suites helps avoid slowdowns.

Disable ATF Debugging and excessive screenshots
Navigate to:
Automated Test Framework → Administration → Properties

Clear Instance Cache and Restart Test Runner
Use cache.do to clear old ATF metadata, especially after an upgrade.

Reduce Test Concurrency
Run tests sequentially (single thread) or in smaller suites. Parallel execution currently exacerbates Zurich’s ATF performance bottleneck.

Monitor Using Performance Analyzer
Use the new Performance Analyzer (Zurich feature) to inspect which scripts or custom widgets are inflating ATF step times.

Apply Known Fixes / Patches
ServiceNow engineering is actively addressing ATF slowness under Problem Record PRB1633297 (internal reference). Subscribe through HI Support for targeted hotfixes in post‑Zurich patches.