---
name: "cmp"
section: "4"
platform: "openbsd"
package: "man"
version: "8.0-current-20261101"
release: "OpenBSD 8.0-current (2026-11-01)"
platforms: ["openbsd"]
url: "https://new.carta.tech/cmp/4"
---

# cmp(4)

chip multi-threading processor

## NAME

**cmp** – chip multi-threading processor

## SYNOPSIS

**cmp\* at mainbus0** **cmp\* at ssm?** **cpu\* at cmp?**

## DESCRIPTION

The **cmp** driver provides support for the chip multi-threading processors such as the Sun UltraSPARC IV and Fujitsu SPARC64 VI processors. It is not a physical device as such, but an abstraction to attach individual CPU cores.

## SEE ALSO

[intro(4)](/intro/4.md)

## HISTORY

The **cmp** driver first appeared in OpenBSD 4.4.

## AUTHORS

The **cmp** driver was written by Mark Kettenis ⟨*kettenis@openbsd.org*⟩.