Re: [PATCH vhost v2 0/7] vdpa/mlx5: Optimze MKEY operations

From: Dragos Tatulea
Date: Wed Sep 11 2024 - 13:06:17 EST




On 11.09.24 10:02, Eugenio Perez Martin wrote:
> On Mon, Sep 9, 2024 at 11:30 AM Dragos Tatulea <dtatulea@xxxxxxxxxx> wrote:
>>
>>
>>
>> On 30.08.24 12:58, Dragos Tatulea wrote:
>>> This series improves the time of .set_map() operations by parallelizing
>>> the MKEY creation and deletion for direct MKEYs. Looking at the top
>>> level MKEY creation/deletion functions, the following improvement can be
>>> seen:
>>>
>>> |-------------------+-------------|
>>> | operation | improvement |
>>> |-------------------+-------------|
>>> | create_user_mr() | 3-5x |
>>> | destroy_user_mr() | 8x |
>>> |-------------------+-------------|
>>>
>>> The last part of the series introduces lazy MKEY deletion which
>>> postpones the MKEY deletion to a later point in a workqueue.
>>>
>>> As this series and the previous ones were targeting live migration,
>>> we can also observe improvements on this front:
>>>
>>> |-------------------+------------------+------------------|
>>> | Stage | Downtime #1 (ms) | Downtime #2 (ms) |
>>> |-------------------+------------------+------------------|
>>> | Baseline | 3140 | 3630 |
>>> | Parallel MKEY ops | 1200 | 2000 |
>>> | Deferred deletion | 1014 | 1253 |
>>> |-------------------+------------------+------------------|
>>>
>>> Test configuration: 256 GB VM, 32 CPUs x 2 threads per core, 4 x mlx5
>>> vDPA devices x 32 VQs (16 VQPs)
>>>
>>> This series must be applied on top of the parallel VQ suspend/resume
>>> series [0].
>>>
>>> [0] https://lore.kernel.org/all/20240816090159.1967650-1-dtatulea@xxxxxxxxxx/
>>>
>>> ---
>>> v2:
>>> - Swapped flex array usage for plain zero length array in first patch.
>>> - Updated code to use Scope-Based Cleanup Helpers where appropriate
>>> (only second patch).
>>> - Added macro define for MTT alignment in first patch.
>>> - Improved commit messages/comments based on review comments.
>>> - Removed extra newlines.
>> Gentle ping for the remaining patches in v2.
>>
>
> Same here, this series is already in MST's branch:
> https://git.kernel.org/pub/scm/linux/kernel/git/mst/vhost.git/commit/?h=vhost&id=d424b079e243128383e88bee79f143ff30b4ec62
>
Ack. Thanks!