ESQL: Track memory in evaluators (#133392)

benchmarks/src/main/java/org/elasticsearch/benchmark/compute/operator/AggregatorBenchmark.java

@@ -643,6 +643,11 @@ public Block eval(Page page) {
                 return mask;
             }
 
+            @Override
+            public long baseRamBytesUsed() {
+                return 0;
+            }
+
             @Override
             public void close() {
                 mask.close();

benchmarks/src/main/java/org/elasticsearch/benchmark/compute/operator/EvalBenchmark.java

@@ -132,7 +132,7 @@ public class EvalBenchmark {
     public String operation;
 
     private static Operator operator(String operation) {
-        return new EvalOperator(driverContext.blockFactory(), evaluator(operation));
+        return new EvalOperator(driverContext, evaluator(operation));
     }
 
     private static EvalOperator.ExpressionEvaluator evaluator(String operation) {

docs/changelog/133392.yaml

@@ -0,0 +1,5 @@
+pr: 133392
+summary: Track memory in evaluators
+area: ES|QL
+type: bug
+issues: []

x-pack/plugin/esql-core/src/main/java/org/elasticsearch/xpack/esql/core/expression/Literal.java

@@ -6,7 +6,9 @@
  */
 package org.elasticsearch.xpack.esql.core.expression;
 
+import org.apache.lucene.util.Accountable;
 import org.apache.lucene.util.BytesRef;
+import org.apache.lucene.util.RamUsageEstimator;
 import org.elasticsearch.TransportVersions;
 import org.elasticsearch.common.io.stream.NamedWriteableRegistry;
 import org.elasticsearch.common.io.stream.StreamInput;
@@ -35,7 +37,9 @@
 /**
  * Literal or constant.
  */
-public class Literal extends LeafExpression {
+public class Literal extends LeafExpression implements Accountable {
+    private static final long BASE_RAM_BYTES_USED = RamUsageEstimator.shallowSizeOfInstance(Literal.class);
+
     public static final NamedWriteableRegistry.Entry ENTRY = new NamedWriteableRegistry.Entry(
         Expression.class,
         "Literal",
@@ -169,6 +173,17 @@ public String nodeString() {
         return toString() + "[" + dataType + "]";
     }
 
+    @Override
+    public long ramBytesUsed() {
+        long ramBytesUsed = BASE_RAM_BYTES_USED;
+        if (value instanceof BytesRef b) {
+            ramBytesUsed += b.length;
+        } else {
+            ramBytesUsed += RamUsageEstimator.sizeOfObject(value);
+        }
+        return ramBytesUsed;
+    }
+
     /**
      * Utility method for creating a literal out of a foldable expression.
      * Throws an exception if the expression is not foldable.

x-pack/plugin/esql/compute/gen/src/main/java/org/elasticsearch/compute/gen/ConvertEvaluatorImplementer.java

@@ -23,6 +23,7 @@
 import javax.lang.model.type.TypeMirror;
 import javax.lang.model.util.Elements;
 
+import static org.elasticsearch.compute.gen.EvaluatorImplementer.baseRamBytesUsed;
 import static org.elasticsearch.compute.gen.Methods.buildFromFactory;
 import static org.elasticsearch.compute.gen.Methods.getMethod;
 import static org.elasticsearch.compute.gen.Types.ABSTRACT_CONVERT_FUNCTION_EVALUATOR;
@@ -98,6 +99,7 @@ private TypeSpec type() {
         builder.addJavadoc("This class is generated. Edit {@code " + getClass().getSimpleName() + "} instead.");
         builder.addModifiers(Modifier.PUBLIC, Modifier.FINAL);
         builder.superclass(ABSTRACT_CONVERT_FUNCTION_EVALUATOR);
+        builder.addField(baseRamBytesUsed(implementation));
 
         for (EvaluatorImplementer.ProcessFunctionArg a : processFunction.args) {
             a.declareField(builder);
@@ -113,6 +115,7 @@ private TypeSpec type() {
         }
         builder.addMethod(processFunction.toStringMethod(implementation));
         builder.addMethod(processFunction.close());
+        builder.addMethod(processFunction.baseRamBytesUsed());
         builder.addType(factory());
         return builder.build();
     }