Merge pull request #380 from JosuaCarl/fix-polynomial-functions

Fix: Fixed application of custom cpu power model

Author: JosuaCarl

CHANGELOG.md

@@ -1,5 +1,6 @@
 # New
 ## Bug Fixes:
+- CPU power model now applied correctly
 - Unintended report value removal
 
 ## Misc:

docs/usage/parameters.md

@@ -154,12 +154,12 @@ The following parameters are currently available:
 
     !!! warning "Experimental feature"
         The `cpuPowerModel` parameter is experimental and may change in future releases.
+
+    A power model function that takes the parameter `coreUsage`.
 
-    Polynomial coefficients for a custom CPU power model (highest degree first).
-    
-    If specified, this overrides TDP-based power draw estimation for CPU cores. The coefficients define a function that returns the **per-core power draw** (in Watts) as a function of core utilization (0–1).
+    If specified, this overrides TDP-based power draw estimation for CPU cores. The function returns the **per-core power draw** (in Watts) as a function of core utilization (0–1).
 
-    **Example**: `[0.5, 10.0]` defines the model `0.5 × coreUsage + 10`
+    **Example**: `{coreUsage -> 0.5 * coreUsage + 10.0}`
 
     **Example visualization**:
 

src/main/nextflow/co2footprint/CO2FootprintCalculator.groovy

@@ -81,8 +81,7 @@ class CO2FootprintCalculator {
         final BigDecimal coreUsage = cpuUsage / (100.0 * numberOfCores)
 
         // Per-core power draw: either custom polynomial model or TDP lookup [W/core]
-        final List<Number> cpuPowerModel = config.cpuPowerModel
-        final BigDecimal powerdrawPerCore = cpuPowerModel ? getPowerDrawFromModel(cpuPowerModel, coreUsage) : tdpDataMatrix.matchModel(cpuModel).getLogicalCoreTDP()
+        final BigDecimal powerdrawPerCore = tdpDataMatrix.matchModel(cpuModel).getLogicalCoreTDP()
 
         /* ===== Memory Information ===== */
 
@@ -127,7 +126,13 @@ class CO2FootprintCalculator {
         /* ===== Energy & Emission Calculation ===== */
 
         // Energy consumption [kWh]
-        BigDecimal rawEnergyProcessor = runtime_h * numberOfCores * powerdrawPerCore * coreUsage * 0.001
+        BigDecimal rawEnergyProcessor
+        if (config.cpuPowerModel) {
+            rawEnergyProcessor = runtime_h * numberOfCores * config.cpuPowerModel(coreUsage) * 0.001
+        }
+        else {
+            rawEnergyProcessor = runtime_h * numberOfCores * powerdrawPerCore * coreUsage * 0.001
+        }
         BigDecimal rawEnergyMemory = runtime_h * memory * powerdrawMem * 0.001
         BigDecimal energy = pue * (rawEnergyProcessor + rawEnergyMemory)
 
@@ -202,23 +207,4 @@ class CO2FootprintCalculator {
         }
         return value != null ? value : defaultValue
     }
-
-    /**
-    * Computes CPU power draw using the configured polynomial model.
-    *
-    * @param coefficients List of polynomial coefficients (highest degree first), as Double or BigDecimal.
-    * @param coreUsage CPU usage as a fraction between 0 and 1.
-    * @return Estimated power draw [W/core], or null if no model configured.
-    */
-    static BigDecimal getPowerDrawFromModel(List<Number> coefficients, BigDecimal coreUsage) {
-        BigDecimal power = 0.0
-        Integer degree = coefficients.size() - 1
-
-        coefficients.eachWithIndex { Number c, Integer i ->
-            power += (c as BigDecimal) * coreUsage ** (degree - i)
-        }
-
-        return power
-    }
-
 }

src/main/nextflow/co2footprint/CO2FootprintConfig.groovy

@@ -114,8 +114,8 @@ class CO2FootprintConfig implements ConfigScope {
     String machineType
 
     @ConfigOption
-    @Description('Polynomial coefficients for CPU power model (highest degree first).')
-    final List<Number> cpuPowerModel
+    @Description('A power model function that takes the parameter `coreUsage`.')
+    final Closure<Number> cpuPowerModel
 
     /**
      * Loads configuration from a map and sets up defaults and fallbacks.
@@ -149,12 +149,9 @@ class CO2FootprintConfig implements ConfigScope {
         ciMarket = getCollect('ciMarket', configMap, usedKeys) as BigDecimal
 
         // Power model
-        cpuPowerModel = getCollect('cpuPowerModel', configMap, usedKeys) as List<BigDecimal>
+        cpuPowerModel = getCollect('cpuPowerModel', configMap, usedKeys) as Closure<BigDecimal>
         if (cpuPowerModel != null) {
-            Integer degree = cpuPowerModel.size() - 1
-            List<String> terms = []
-            cpuPowerModel.eachWithIndex { Number c, Integer i -> terms.add("${c}*x^${degree - i}") }
-            log.info("Using custom CPU power model: f(x) = " + terms.join(" + "))
+            log.info("Using custom CPU power model.")
         }
 
         // Powerdraw factors

src/test/nextflow/co2footprint/CO2FootprintCalculatorTest.groovy

@@ -37,7 +37,7 @@ class CO2FootprintCalculatorTest extends Specification{
         def traceRecord = new TraceRecord()
         traceRecord.task_id = '1'
         traceRecord.realtime = (1 as Long) * (3600000 as Long)
-        traceRecord.cpus = 1
+        traceRecord.cpus = 2
         traceRecord.cpu_model = cpuModel
         traceRecord.'%cpu' = 100.0
         traceRecord.memory = (7 as Long) * (1024**3 as Long)
@@ -52,13 +52,13 @@ class CO2FootprintCalculatorTest extends Specification{
         round(co2Record.store.CO2e as Double) == expectedCO2
 
         where:
-        cpuModel           | configMap                      || expectedEnergy   | expectedCO2
-        "Unknown model"    | [:]                            || 14.06            | 6.75
-        "AMD EPYC 7251"    | [:]                            || 10.11            | 4.85
-        "Unknown model"    | [pue: 1.4]                     || 19.68            | 9.45
-        "Unknown model"    | [location: 'DE']               || 14.06            | 4.69
-        "Unknown model"    | [ci: 338.66]                   || 14.06            | 4.76
-        "AMD EPYC 7251"    | [cpuPowerModel: [0.5d, 10.0d]] || 13.11            | 6.29
+        cpuModel           | configMap                                              || expectedEnergy   | expectedCO2
+        "Unknown model"    | [:]                                                    || 14.06            | 6.75
+        "AMD EPYC 7251"    | [:]                                                    || 10.11            | 4.85
+        "Unknown model"    | [pue: 1.4]                                             || 19.68            | 9.45
+        "Unknown model"    | [location: 'DE']                                       || 14.06            | 4.69
+        "Unknown model"    | [ci: 338.66]                                           || 14.06            | 4.76
+        "AMD EPYC 7251"    | [cpuPowerModel: {coreUsage -> 0.5 * coreUsage + 10.0}] || 23.11            | 11.09
     }
 
     // ------ Equivalences Calculation ------
@@ -125,25 +125,7 @@ class CO2FootprintCalculatorTest extends Specification{
         4L*1024**3         | null               | false           | 4L              // requested used (required null)
         null               | null               | true            | null            // throws error (both null)
     }
-
-    def 'test power draw from polynomial model'() {
-        given:
-        def computer = new CO2FootprintCalculator(null, null)
-
-        expect:
-        computer.getPowerDrawFromModel(coeffs, usage as BigDecimal).round(6) == expected
-
-        where:
-        coeffs                     | usage || expected
-        [2.0, 5.0]                 | 0     || 5.0       // 2*x + 5 at x=0
-        [2.0, 5.0]                 | 50    || 105.0     // 2*50 + 5
-        [2.0, 5.0]                 | 100   || 205.0     // 2*100 + 5
-        [1.0, 0.0, 0.0]            | 2     || 4.0       // x² at x=2
-        [1.0, 0.0, 0.0]            | 5     || 25.0      // x² at x=5
-        [0.5, 10.0]                | 20    || 20.0      // 0.5*20 + 10
-        [BigDecimal.valueOf(1), 5] | 3     || 8.0       // supports BigDecimal coeffs too
-    }
-
+    
     def "Determination of number of CPUs"() {
         given:
         def traceRecord = new TraceRecord()

src/test/nextflow/co2footprint/CO2FootprintConfigTest.groovy

@@ -127,7 +127,7 @@ class CO2FootprintConfigTest extends Specification {
 
     def 'should log custom CPU power model as polynomial'() {
         given:
-        def configMap = [cpuPowerModel: [2.5, 1.3, 0.7], machineType: 'local']
+        def configMap = [cpuPowerModel: {x -> 2.5 * x**2 + 1.3 * x + 0.7}, machineType: 'local']
         def processMap = [:]
 
         // Set up log capturing
@@ -141,7 +141,7 @@ class CO2FootprintConfigTest extends Specification {
 
         then:
         List<String> logMessages = listAppender.list*.formattedMessage
-        logMessages.any {String message -> message.contains("Using custom CPU power model: f(x) = 2.5*x^2 + 1.3*x^1 + 0.7*x^0") }
+        logMessages.any {String message -> message.contains("Using custom CPU power model.") }
     }
 
     // Helper method to validate default properties