[dpdk-dev,v2,2/2] doc: update PMD options for mlx5
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Commit Message
Enhanced multi-packet send mode is newly introduced for ConnectX-5 families
of adaptors.
Signed-off-by: Yongseok Koh <yskoh@mellanox.com>
---
doc/guides/nics/mlx5.rst | 31 +++++++++++++++++++++++++++----
1 file changed, 27 insertions(+), 4 deletions(-)
Comments
Saturday, March 11, 2017 1:14 AM, Yongseok Koh:
> Enhanced multi-packet send mode is newly introduced for ConnectX-5
> families of adaptors.
>
> Signed-off-by: Yongseok Koh <yskoh@mellanox.com>
> ---
> doc/guides/nics/mlx5.rst | 31 +++++++++++++++++++++++++++----
> 1 file changed, 27 insertions(+), 4 deletions(-)
>
> diff --git a/doc/guides/nics/mlx5.rst b/doc/guides/nics/mlx5.rst index
> 41f3a472e..0783aebdd 100644
> --- a/doc/guides/nics/mlx5.rst
> +++ b/doc/guides/nics/mlx5.rst
> @@ -183,10 +183,17 @@ Run-time configuration
>
> - ``txq_mpw_en`` parameter [int]
>
> - A nonzero value enables multi-packet send. This feature allows the TX
> - burst function to pack up to five packets in two descriptors in order to
> - save PCI bandwidth and improve performance at the cost of a slightly
> - higher CPU usage.
> + A nonzero value enables multi-packet send (MPS) for ConnectX-4 Lx and
> + enhanced multi-packet send (Enhanced MPS) for ConnectX-5. MPS allows
> + the TX burst function to pack up multiple packets in a single
> + descriptor session in order to save PCI bandwidth and improve
> + performance at the cost of a slightly higher CPU usage. When
> + ``txq_inline`` is set along with ``txq_mpw_en``, TX burst function
> + tries to copy entire packet data on to TX descriptor instead of
> + including pointer of packet only if there is enough room remained in
> + the descriptor. ``txq_inline`` sets per-descriptor space for either
> + pointers or inlined packets. In addition, Enhanced MPS supports
> + hybrid mode - mixing inlined packets and pointers in the same descriptor.
>
> This option cannot be used in conjunction with ``tso`` below. When ``tso``
> is set, ``txq_mpw_en`` is disabled.
> @@ -194,6 +201,22 @@ Run-time configuration
> It is currently only supported on the ConnectX-4 Lx and ConnectX-5
> families of adapters. Enabled by default.
>
> +- ``txq_mpw_hdr_dseg_en`` parameter [int]
> +
> + A nonzero value enables including two pointers in the first block of
> + TX descriptor. This can be used to lessen CPU load for memory copy.
> +
> + Effective only when Enhanced MPS is supported. Disabled by default.
> +
> +- ``txq_max_inline_len`` parameter [int]
> +
> + Maximum size of packet to be inlined. This limits the size of packet
> + to be inlined. If the size of a packet is larger than configured
> + value, the packet isn't inlined even though there's enough space
> + remained in the descriptor. Instead, the packet is included with pointer.
> +
> + Effective only when Enhanced MPS is supported. The default value is 256.
> +
> - ``tso`` parameter [int]
>
> A nonzero value enables hardware TSO.
> --
Acked-by: Shahaf Shuler <shahafs@mellanox.com>
> 2.11.0
@@ -183,10 +183,17 @@ Run-time configuration
- ``txq_mpw_en`` parameter [int]
- A nonzero value enables multi-packet send. This feature allows the TX
- burst function to pack up to five packets in two descriptors in order to
- save PCI bandwidth and improve performance at the cost of a slightly
- higher CPU usage.
+ A nonzero value enables multi-packet send (MPS) for ConnectX-4 Lx and
+ enhanced multi-packet send (Enhanced MPS) for ConnectX-5. MPS allows the
+ TX burst function to pack up multiple packets in a single descriptor
+ session in order to save PCI bandwidth and improve performance at the
+ cost of a slightly higher CPU usage. When ``txq_inline`` is set along
+ with ``txq_mpw_en``, TX burst function tries to copy entire packet data
+ on to TX descriptor instead of including pointer of packet only if there
+ is enough room remained in the descriptor. ``txq_inline`` sets
+ per-descriptor space for either pointers or inlined packets. In addition,
+ Enhanced MPS supports hybrid mode - mixing inlined packets and pointers
+ in the same descriptor.
This option cannot be used in conjunction with ``tso`` below. When ``tso``
is set, ``txq_mpw_en`` is disabled.
@@ -194,6 +201,22 @@ Run-time configuration
It is currently only supported on the ConnectX-4 Lx and ConnectX-5
families of adapters. Enabled by default.
+- ``txq_mpw_hdr_dseg_en`` parameter [int]
+
+ A nonzero value enables including two pointers in the first block of TX
+ descriptor. This can be used to lessen CPU load for memory copy.
+
+ Effective only when Enhanced MPS is supported. Disabled by default.
+
+- ``txq_max_inline_len`` parameter [int]
+
+ Maximum size of packet to be inlined. This limits the size of packet to
+ be inlined. If the size of a packet is larger than configured value, the
+ packet isn't inlined even though there's enough space remained in the
+ descriptor. Instead, the packet is included with pointer.
+
+ Effective only when Enhanced MPS is supported. The default value is 256.
+
- ``tso`` parameter [int]
A nonzero value enables hardware TSO.