Re: [PATCH v7 2/2] gpu/tests/buddy: add dirty tracker performance KUnit test

Matthew Auld <[email protected]> Thu, 6 Aug 2026 16:39:08 +0100
Newsgroups org.freedesktop.lists.amd-gfx,org.freedesktop.lists.dri-devel,org.freedesktop.lists.intel-gfx,org.freedesktop.lists.intel-xe
Message-ID <[email protected]>
On 31/07/2026 08:07, Arunpravin Paneer Selvam wrote:
> Add gpu_test_buddy_dirty_tracker_performance to demonstrate the key
> advantage of the decoupled dirty-tracker design over the old dual-tree
> / force_merge approach.
> 
> The test runs two scenarios on a 4 GiB pool after alternating
> clear/dirty fragmentation at 4 KiB granularity:
> 
>    1. Contiguous 4 GiB alloc: the old design requires __force_merge()
>       to rebuild max_order from scratch; the new design coalesces during
>       free() so the alloc is O(log N).
> 
>         old (force_merge) - 71 ms
>         dirty tracker design - 17 ms
> 
>    2. Repeated 256 KiB alloc throughput: the old design pays
>       __force_merge() on every alloc; the new design does not.
> 
>         old (force_merge) - 95 ms
>         dirty tracker design - 24 ms
> 
> Assisted-by: Claude:claude-opus-4-8
> Cc: Matthew Auld <[email protected]>
> Cc: Christian König <[email protected]>
> Signed-off-by: Arunpravin Paneer Selvam <[email protected]>

Reviewed-by: Matthew Auld <[email protected]>