N8N: RangeError: Invalid string length in Push.relayViaPubSub - Workflow succeeds but shows as failed

I'm experiencing a persistent RangeError: Invalid string length when processing large datasets in n8n. The workflow executes successfully and processes all data correctly, but fails during the post-execution phase, causing the execution to be marked as "failed" despite successful completion.

Error Details

Error Message:

There was a problem running hook "workflowExecuteAfter" RangeError: Invalid string length

at JSON.stringify (<anonymous>)

at Push.relayViaPubSub (/usr/local/lib/node_modules/n8n/src/push/index.ts:221:56)

at Push.send (/usr/local/lib/node_modules/n8n/src/push/index.ts:169:9)

at ExecutionLifecycleHooks.<anonymous> (/usr/local/lib/node_modules/n8n/src/execution-lifecycle/execution-lifecycle-hooks.ts:149:17)

Key Details:

Dataset Size: Processing ~1159 items per execution

n8n Version: 1.98.2

Setup: Docker deployment with Queue mode + Redis + 2 workers

Workflow Status: Actually succeeds ("Worker finished execution successfully"), but marked as failed due to Push error

What I've Tried

Configuration Attempts:

bash# Push Backend Settings

N8N_PUSH_BACKEND=none # Tried both none and websocket

N8N_DISABLE_LIFECYCLE_HOOKS=true # Attempted to disable hooks

N8N_DISABLE_UI=true # On workers only

# Execution Data Settings

EXECUTIONS_DATA_SAVE_ON_SUCCESS=none # Tried to minimize data storage

EXECUTIONS_DATA_SAVE_ON_PROGRESS=false

EXECUTIONS_DATA_COMPRESS=true

# Memory Settings

NODE_OPTIONS=--max-old-space-size=40960 # Main container

NODE_OPTIONS=--max-old-space-size=61440 # Workers

N8N_PAYLOAD_SIZE_MAX=26843545600

Architecture:

Main container: UI + Queue management

2 Worker containers: Processing only with N8N_PUSH_BACKEND=none

Redis queue with increased timeouts

PostgreSQL database

Root Cause Analysis

The issue appears to be a JavaScript engine limitation rather than an n8n configuration problem:

JSON.stringify() Limit: JavaScript has a maximum string length of ~268MB

Large Execution Data: When processing 1159 items, the serialized execution data exceeds this limit

Push Mechanism: n8n tries to serialize the entire execution result for frontend updates, hitting the string length limit

Lifecycle Hook Issue: Despite N8N_DISABLE_LIFECYCLE_HOOKS=true, the hooks still execute and attempt serialization

The Paradox

✅ Workflow Logic: Completes successfully, all API calls work, data is processed

✅ Worker Logs: "Worker finished execution successfully"

❌ UI Status: Shows as "Failed" due to Push.relayViaPubSub error

❌ Queue Management: Job gets marked as failed, triggering retries

Questions for the Community

Is there a way to completely disable the Push mechanism that bypasses lifecycle hooks entirely?

Can execution data serialization be made optional for large workflows where UI updates aren't critical?

Are there plans to implement streaming serialization for large execution data instead of single JSON.stringify calls?

Has anyone found a configuration that prevents this specific lifecycle hook from executing on large datasets?

Workaround Needed

I'm willing to accept:

No real-time UI updates during execution

Manual status checking via page refresh

Minimal execution data storage

But I need the execution to be marked as "successful" when it actually succeeds, not failed due to UI update serialization issues.

Technical Environment

Docker Compose setup

Queue mode with Redis

PostgreSQL database

2 dedicated worker containers

48GB Redis max memory

Processing workflows with 1000+ items regularly

Any insights, alternative configurations, or workarounds would be greatly appreciated! This seems to be a fundamental limitation where workflow success is being overshadowed by UI update failures.

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