---
name: "hwloc-dump-hwdata"
section: "1"
platform: "linux"
package: "hwloc"
version: "2.15.0-1"
release: "Arch Linux 2026-11-01"
platforms: ["linux"]
url: "https://new.carta.tech/hwloc-dump-hwdata"
---

# hwloc-dump-hwdata(1)

Dump topology and locality information from hardware tables

## NAME

hwloc-dump-hwdata - Dump topology and locality information from hardware tables

## SYNOPSIS

**hwloc-dump-hwdata** \[*options*\]

## OPTIONS

- **-o \<dir\>**

  save output files to directory \<dir\> instead of the default */usr/var/run/hwloc/* that was specified at configure time.

  You may want to set the HWLOC\_DUMPED\_HWDATA\_DIR environment variable as well so that the hwloc library looks for dumped files in that same directory.

- **--version**

  Report version and exit.

- **-h** **--help**

  Display help message and exit.

## DESCRIPTION

hwloc may benefit from some locality and topology information from SMBIOS or ACPI tables. They are accessible from raw hardware files under directories such /sys/firmware/dmi/ or /sys/firmware/acpi/ on Linux. These files are usually only accessible to root, and they only exist when there is *dmi-sysfs* support in the Linux kernel.

The hwloc-dump-hwdata tool dumps the useful contents of such files into human-readable and world-accessible files. The intent is to run the tool once during boot and have the main (non-privileged) hwloc library gather information from these human-readable files.

**hwloc-dump-hwdata is currently only useful for Intel Xeon Phi processors** (Knights Landing and Knights Mill).

The current list of dumped information is:

- **Intel Xeon Phi processor memory, cache and clustering configuration**

  gathered from specific SMBIOS entries such as */sys/firmware/dmi/entries/14-\** and */sys/firmware/dmi/entries/160-\**, and saved in file *knl\_memoryside\_cache*.

## SEE ALSO

[hwloc(7)](/hwloc/7.md), [lstopo(1)](/lstopo/1.md)