Re: [RFC PATCH 16/30] mm: enable slab allocation tagging for kmalloc and friends

From: Roman Gushchin
Date: Thu Sep 01 2022 - 19:50:48 EST


On Tue, Aug 30, 2022 at 02:49:05PM -0700, Suren Baghdasaryan wrote:
> Redefine kmalloc, krealloc, kzalloc, kcalloc, etc. to record allocations
> and deallocations done by these functions.

One particular case when this functionality might be very useful:
in the past we've seen examples (at Fb) where it was hard to understand
the difference between slab memory sizes of two different kernel versions
due to slab caches merging. Once a slab cache is merged with another large
cache, this data is pretty much lost. So I definetely see value in stats which
are independent from kmem caches.

The performance overhead is a concern here, so more data would be useful.

Thanks!