> Source: [sk185068](https://support.checkpoint.com/results/sk/sk185068)

# sk185068 - Security Gateway tempory freeze due to high CPU utilization on a single core 

| Property | Value |
|----------|-------|
| Solution ID | sk185068 |
| Date Created | 2026-06-18 |
| Last Modified | 2026-08-17 |
| Technical Level | Advanced |
| Products | Security Gateway |
| Versions | R82.10, R82, R81.20 |

## Symptoms

- * The Security Gateway temporarily freezes, causing traffic disruption for several minutes, but does not trigger a cluster failover.

* High CPU utilization is observed on a single firewall core or instance, often with repeated CPU spikes around the time of the incident.

* Running this command on the Security Gateway:   

  `hcp -r "Cpu spikes"` or following the procedure in [sk166454 - CPU Spike Detective](https://support.checkpoint.com/results/sk/sk166454)
  generates this output:  

  *"fwk0_6 libfw_kern_64_us_6.so \[.\] ws_stream_iterate.cold.0"*

* Logs may show:  

  * Blocked handlers
  * IOCTL delays
  * Errors related to global connection lookup/priority queue enqueue.

  <br />

## Cause

The issue occurs when the Security Gateway processes a heavy connection using Web Streaming inspection. Under certain conditions, the `ws_stream_iterate` code path can cause inefficient iteration on a single firewall instance.  
As a result, one CPU core becomes highly utilized, which can temporarily impact traffic handling and system responsiveness.

## Solution

This solution requires authentication. Please log in to view the full solution.

---

# Agent Instructions

This content is from the Check Point Support Center (https://support.checkpoint.com), the official knowledge base for Check Point cybersecurity products.

## Navigating This Knowledge Base

- **Complete index**: [llms.txt](https://support.checkpoint.com/llms.txt)
- **All SK articles**: [SecureKnowledge Sitemap](https://support.checkpoint.com/sitemaps/secureknowledge-sitemap-index.xml)
- **SK article URL pattern**: `https://support.checkpoint.com/results/sk/{skId}`
- **Markdown responses**: AI bot User-Agents automatically receive `text/markdown` content