Migration Guide: Failure and Termination Rules (v3.0.2.5 → v3.0.2.6+)

This guide helps you migrate your existing test configurations to the new inline metric expression format.

Overview of Changes

Feature	Old Format (Deprecated)	New Format (v3.0.2.6+)
Failure Rules	failureCriteria with individual fields	failureRules with inline metric expressions
Termination Rules	terminationRules with individual fields	terminationRules with inline metric expressions
Status Codes	Comma-separated list: "403,401,500"	Comparison expression: ">= 400", "between 400 and 499"

Failure Rules Migration

Old Format (Removed)

failureCriteria:
  maxErrorRate: 0.10
  errorStatusCodes: "404,403,500"
  maxP90: 250
  maxP50: 200
  maxP10: 150
  maxAvg: 180

New Format

failureRules:
  - metric: "ErrorRate > 0.10"
    errorStatusCodes: ">= 400"
  - metric: "TotalTime.P90 > 250"
  - metric: "TotalTime.P50 > 200"
  - metric: "TotalTime.P10 > 150"
  - metric: "TotalTime.Avg > 180"

Key Differences

1. Property name changed: failureCriteria → failureRules
2. Array of rules: Each metric condition is now a separate rule
3. Inline expressions: Use operators like >, >=, <, <=, =, !=
4. Status code format: Changed from comma-separated to comparison expressions

Termination Rules Migration

Old Format (Removed)

terminationRules:
  - maxErrorRate: 0.2
    errorStatusCodes: "404,403,500"
    maxP90: 200
    gracePeriod: "00:00:10"
  - maxP50: 400
    gracePeriod: "00:00:15"

New Format

terminationRules:
  - metric: "ErrorRate > 0.2"
    errorStatusCodes: ">= 400"
    gracePeriod: "00:00:10"
  - metric: "TotalTime.P90 > 200"
    gracePeriod: "00:00:10"
  - metric: "TotalTime.P50 > 400"
    gracePeriod: "00:00:15"

Key Differences

1. Metric field required: Each rule must have a metric field with an inline expression
2. One metric per rule: Each metric condition is now a separate rule (no combining maxErrorRate and maxP90 in one rule)
3. Grace period format: Unchanged (TimeSpan format "HH:mm:ss")

Status Code Expressions

Old Format

errorStatusCodes: "403,401,500"

New Format Options

Expression	Description
">= 500"	All 5xx server errors
">= 400"	All 4xx and 5xx errors
"between 400 and 499"	Only 4xx client errors
"= 429"	Only rate limiting errors
"= 0"	Connectivity failures (DNS, timeout, connection refused)
">= 0"	All errors including connectivity failures

Special Note on Status Code 0

The status code 0 represents connectivity failures, including:

• DNS resolution failures
• Connection refused
• Connection timeout
• SSL/TLS handshake failures
• Network unreachable

Metric Expression Reference

Format

MetricName[.Statistic] Operator Threshold

Available Metrics

Metric	Statistics	Example
ErrorRate	(none)	"ErrorRate > 0.05"
TotalTime	.P10, .P50, .P90, .P99, .Avg, .Min, .Max	"TotalTime.P90 > 250"
Throughput	(none)	"Throughput < 100"

Operators

• > - Greater than
• >= - Greater than or equal
• < - Less than
• <= - Less than or equal
• = - Equal
• != - Not equal
• between X and Y - Range comparison (inclusive)

CLI Options

New CLI Options for Rules

Failure Rules:

lps --url https://example.com -rc 1000 --failurerule "ErrorRate > 0.05;>= 500"  --failurerule "TotalTime.P90 > 250"

Format: "metric[;errorStatusCodes]"

Termination Rules:

lps --url https://example.com -rc 1000 --terminationrule "ErrorRate > 0.10;00:05:00;>= 500" --terminationrule "TotalTime.P90 > 500;00:00:30"

Format: "metric;gracePeriod[;errorStatusCodes]"

Complete Migration Example

Before (v3.0.2.5 and earlier)

name: OldFormatExample
rounds:
  - name: TestRound
    numberOfClients: 50
    iterations:
      - name: APITest
        httpRequest:
          url: https://api.example.com/endpoint
          method: GET
        failureCriteria:
          maxErrorRate: 0.10
          errorStatusCodes: "500,502,503"
          maxP90: 500
        terminationRules:
          - maxErrorRate: 0.25
            errorStatusCodes: "500,502,503"
            gracePeriod: "00:00:30"
          - maxP90: 1000
            gracePeriod: "00:00:15"

After (v3.0.2.6+)

name: NewFormatExample
rounds:
  - name: TestRound
    numberOfClients: 50
    iterations:
      - name: APITest
        httpRequest:
          url: https://api.example.com/endpoint
          method: GET
        failureRules:
          - metric: "ErrorRate > 0.10"
            errorStatusCodes: ">= 500"
          - metric: "TotalTime.P90 > 500"
        terminationRules:
          - metric: "ErrorRate > 0.25"
            errorStatusCodes: ">= 500"
            gracePeriod: "00:00:30"
          - metric: "TotalTime.P90 > 1000"
            gracePeriod: "00:00:15"

FAQ

Q: Can I still use the old format?

A: No. The old format has been permanently removed in v3.0.2.6. You must migrate to the new format.

Q: What happens if I run an old config with the new version?

A: The test will fail validation with an error indicating the old properties are not recognized.

Q: Can I combine multiple metrics in one rule?

A: No. Each metric must be its own rule. This provides more flexibility and clearer semantics.

Q: How do I include connectivity failures in my error count?

A: Use status code 0 in your expression: errorStatusCodes: ">= 0" or errorStatusCodes: "= 0" for only connectivity failures.