fix(executor): use performance.now() for precise block timing

Replace Date.now() with performance.now() for timing measurements in
the executor to provide sub-millisecond precision. This fixes timing
discrepancies with fast-executing blocks like the start block where
millisecond precision was insufficient.

Changes:
- block-executor.ts: Use performance.now() for block execution timing
- engine.ts: Use performance.now() for overall execution timing

Co-authored-by: emir <emir@simstudio.ai>

apps/sim/executor/execution/block-executor.ts

@@ -71,7 +71,7 @@ export class BlockExecutor {
       this.callOnBlockStart(ctx, node, block)
     }
 
-    const startTime = Date.now()
+    const startTime = performance.now()
     let resolvedInputs: Record<string, any> = {}
 
     const nodeMetadata = this.buildNodeMetadata(node)
@@ -145,7 +145,7 @@ export class BlockExecutor {
         })) as NormalizedBlockOutput
       }
 
-      const duration = Date.now() - startTime
+      const duration = performance.now() - startTime
 
       if (blockLog) {
         blockLog.endedAt = new Date().toISOString()
@@ -221,7 +221,7 @@ export class BlockExecutor {
     isSentinel: boolean,
     phase: 'input_resolution' | 'execution'
   ): NormalizedBlockOutput {
-    const duration = Date.now() - startTime
+    const duration = performance.now() - startTime
     const errorMessage = normalizeError(error)
     const hasResolvedInputs =
       resolvedInputs && typeof resolvedInputs === 'object' && Object.keys(resolvedInputs).length > 0

apps/sim/executor/execution/engine.ts

@@ -101,7 +101,7 @@ export class ExecutionEngine {
   }
 
   async run(triggerBlockId?: string): Promise<ExecutionResult> {
-    const startTime = Date.now()
+    const startTime = performance.now()
     try {
       this.initializeQueue(triggerBlockId)
 
@@ -125,8 +125,8 @@ export class ExecutionEngine {
         return this.buildPausedResult(startTime)
       }
 
-      const endTime = Date.now()
-      this.context.metadata.endTime = new Date(endTime).toISOString()
+      const endTime = performance.now()
+      this.context.metadata.endTime = new Date().toISOString()
       this.context.metadata.duration = endTime - startTime
 
       if (this.cancelledFlag) {
@@ -146,8 +146,8 @@ export class ExecutionEngine {
         metadata: this.context.metadata,
       }
     } catch (error) {
-      const endTime = Date.now()
-      this.context.metadata.endTime = new Date(endTime).toISOString()
+      const endTime = performance.now()
+      this.context.metadata.endTime = new Date().toISOString()
       this.context.metadata.duration = endTime - startTime
 
       if (this.cancelledFlag) {
@@ -433,8 +433,8 @@ export class ExecutionEngine {
   }
 
   private buildPausedResult(startTime: number): ExecutionResult {
-    const endTime = Date.now()
-    this.context.metadata.endTime = new Date(endTime).toISOString()
+    const endTime = performance.now()
+    this.context.metadata.endTime = new Date().toISOString()
     this.context.metadata.duration = endTime - startTime
     this.context.metadata.status = 'paused'