---
name: "ibv_query_port_speed"
section: "3"
platform: "linux"
package: "rdma-core"
version: "65.0-1"
release: "Arch Linux 2026-11-01"
platforms: ["linux"]
url: "https://new.carta.tech/ibv_query_port_speed"
---

# ibv\_query\_port\_speed(3)

query an RDMA port’s effective bandwidth in 100Mb/s granularity

## NAME

ibv\_query\_port\_speed - query an RDMA port’s effective bandwidth in 100Mb/s granularity

## SYNOPSIS

-

  ```
  #include <infiniband/verbs.h>
  int ibv_query_port_speed(struct ibv_context *context, uint32_t port_num, uint64_t *port_speed);
  ```

## DESCRIPTION

**ibv\_query\_port\_speed()** Queries the device of the context at the given port number for the effective bandwidth of the port in 100Mb/s granularity.

## ARGUMENTS

- *context*

  -

  ```
    The device context.
  ```

- *port\_num*

  -

  ```
    The device port number which needs to be queried.
  ```

- *port\_speed*

  The effective bandwidth of port for device context in a granularity of 100 Mb/s

## RETURN VALUE

**ibv\_query\_port\_speed()** Returns 0 on success, or the value of errno on failure (which indicates the failure reason)

## NOTES

port\_speed pointer value is valid only when the function returns 0.

## SEE ALSO

[**ibv\_query\_port**(3)](/ibv_query_port/3.md)

## AUTHOR

Patrisious Haddad ⟨phaddad@nvidia.com⟩\\c  Or Har-Toov ⟨ohartoov@nvidia.com⟩\\c