[PATCH] doc: improve event core description in vDPA mlx5

[PATCH] doc: improve event core description in vDPA mlx5

[Matan Azrad]

The event core is mlx5 vDPA driver devarg that selects the CPU core for
the internal timer thread used to manage data-path events into the
driver.

Emphasize that this CPU should be isolated for vDPA mlx5 devices only in
order to save the performance and latency of the device.

Signed-off-by: Matan Azrad <matan@nvidia.com>
---
 doc/guides/vdpadevs/mlx5.rst | 9 +++++++--
 1 file changed, 7 insertions(+), 2 deletions(-)

diff --git a/doc/guides/vdpadevs/mlx5.rst b/doc/guides/vdpadevs/mlx5.rst
index 9767fbe42d..3b5ce6df38 100644
--- a/doc/guides/vdpadevs/mlx5.rst
+++ b/doc/guides/vdpadevs/mlx5.rst
@@ -86,8 +86,13 @@ for an additional list of options shared with other mlx5 drivers.
 
 - ``event_core`` parameter [int]
 
-  CPU core number to set polling thread affinity to, default to control plane
-  cpu.
+  The CPU core number of the timer thread, default: EAL main lcore.
+
+.. note::
+
+   This core can be shared among different mlx5 vDPA devices as `event_core` but
+   using it also for other tasks may affect the performance and the latency of the
+   mlx5 vDPA devices.
 
 - ``max_conf_threads`` parameter [int]
 
-- 
2.25.1

RE: [PATCH] doc: improve event core description in vDPA mlx5

[Xia, Chenbo]

> -----Original Message-----
> From: Matan Azrad <matan@nvidia.com>
> Sent: Sunday, November 13, 2022 5:22 PM
> To: Maxime Coquelin <maxime.coquelin@redhat.com>
> Cc: dev@dpdk.org
> Subject: [PATCH] doc: improve event core description in vDPA mlx5
> 
> The event core is mlx5 vDPA driver devarg that selects the CPU core for
> the internal timer thread used to manage data-path events into the
> driver.
> 
> Emphasize that this CPU should be isolated for vDPA mlx5 devices only in
> order to save the performance and latency of the device.
> 
> Signed-off-by: Matan Azrad <matan@nvidia.com>
> ---
>  doc/guides/vdpadevs/mlx5.rst | 9 +++++++--
>  1 file changed, 7 insertions(+), 2 deletions(-)
> 
> diff --git a/doc/guides/vdpadevs/mlx5.rst b/doc/guides/vdpadevs/mlx5.rst
> index 9767fbe42d..3b5ce6df38 100644
> --- a/doc/guides/vdpadevs/mlx5.rst
> +++ b/doc/guides/vdpadevs/mlx5.rst
> @@ -86,8 +86,13 @@ for an additional list of options shared with other
> mlx5 drivers.
> 
>  - ``event_core`` parameter [int]
> 
> -  CPU core number to set polling thread affinity to, default to control
> plane
> -  cpu.
> +  The CPU core number of the timer thread, default: EAL main lcore.
> +
> +.. note::
> +
> +   This core can be shared among different mlx5 vDPA devices as
> `event_core` but
> +   using it also for other tasks may affect the performance and the
> latency of the
> +   mlx5 vDPA devices.
> 
>  - ``max_conf_threads`` parameter [int]
> 
> --
> 2.25.1

Reviewed-by: Chenbo Xia <chenbo.xia@intel.com>

Re: [PATCH] doc: improve event core description in vDPA mlx5

[Thomas Monjalon]

> > The event core is mlx5 vDPA driver devarg that selects the CPU core for
> > the internal timer thread used to manage data-path events into the
> > driver.
> > 
> > Emphasize that this CPU should be isolated for vDPA mlx5 devices only in
> > order to save the performance and latency of the device.
> > 
> > Signed-off-by: Matan Azrad <matan@nvidia.com>
> 
> Reviewed-by: Chenbo Xia <chenbo.xia@intel.com>

Applied, thanks.