dmstats - Linux

Overview

dmstats is a tool for displaying statistics about the Direct Memory Access (DMA) subsystem on Linux systems. It provides detailed information about DMA channels, controllers, and buses, allowing administrators to monitor and diagnose DMA-related issues.

Syntax

dmstats [options]

Options/Flags

  • -a, –all: Display statistics for all DMA channels and controllers.
  • -c, –controller: Display statistics for a specific DMA controller.
  • -d, –device: Display statistics for a specific DMA device.
  • -h, –help: Display help information.
  • -v, –verbose: Increase verbosity level.
  • -w, –watch: Continuously monitor DMA statistics.

Examples

Display statistics for all DMA devices:

dmstats -a

Display statistics for a specific DMA controller:

dmstats -c 0

Monitor DMA statistics continuously:

dmstats -w

Common Issues

Error: No DMA devices found: This usually indicates that the DMA subsystem is not initialized or is not supported on the system. Check if the DMA driver is loaded and if the DMA controller is enabled in the BIOS.

Integration

Combine with other commands:

  • Use dmstats with dmesg to track DMA-related kernel messages.
  • Use dmstats with perf to analyze DMA performance and identify bottlenecks.

Related Commands

  • dmesg
  • perf
  • iostat