SoftIRQ statistics
SoftIRQ statistics
Plugin: proc.plugin Module: /proc/softirqs
Overview
In the Linux kernel, handling of hardware interrupts is split into two halves: the top half and the bottom half. The top half is the routine that responds immediately to an interrupt, while the bottom half is deferred to be processed later.
Softirqs are a mechanism in the Linux kernel used to handle the bottom halves of interrupts, which can be deferred and processed later in a context where it’s safe to enable interrupts.
The actual work of handling the interrupt is offloaded to a softirq and executed later when the system decides it’s a good time to process them. This helps to keep the system responsive by not blocking the top half for too long, which could lead to missed interrupts.
Monitoring /proc/softirqs is useful for:
-
Performance tuning: A high rate of softirqs could indicate a performance issue. For instance, a high rate of network softirqs (
NET_RXandNET_TX) could indicate a network performance issue. -
Troubleshooting: If a system is behaving unexpectedly, checking the softirqs could provide clues about what is going on. For example, a sudden increase in block device softirqs (BLOCK) might indicate a problem with a disk.
-
Understanding system behavior: Knowing what types of softirqs are happening can help you understand what your system is doing, particularly in terms of how it’s interacting with hardware and how it’s handling interrupts.
This collector is supported on all platforms.
This collector supports collecting metrics from multiple instances of this integration, including remote instances.
Default Behavior
Auto-Detection
This integration doesn’t support auto-detection.
Limits
The default configuration for this integration does not impose any limits on data collection.
Performance Impact
The default configuration for this integration is not expected to impose a significant performance impact on the system.
Setup
Prerequisites
No action required.
Configuration
File
There is no configuration file.
Options
There are no configuration options.
Examples
There are no configuration examples.
Metrics
Metrics grouped by scope.
The scope defines the instance that the metric belongs to. An instance is uniquely identified by a set of labels.
Per SoftIRQ statistics instance
This scope has no labels.
Metrics:
| Metric | Dimensions | Unit |
|---|---|---|
| system.softirqs | a dimension per softirq | softirqs/s |
Per cpu core
Labels:
| Label | Description |
|---|---|
| cpu | TBD |
Metrics:
| Metric | Dimensions | Unit |
|---|---|---|
| cpu.softirqs | a dimension per softirq | softirqs/s |
Alerts
There are no alerts configured by default for this integration.