Re: [PATCH] zswap: change zswap's default allocator to zsmalloc

From: Johannes Weiner
Date: Mon Sep 11 2023 - 18:43:10 EST


On Fri, Sep 08, 2023 at 04:51:15PM -0700, Nhat Pham wrote:
> Out of zswap's 3 allocators, zsmalloc is the clear superior in terms of
> memory utilization, both in theory and as observed in practice, with its
> high storage density and low internal fragmentation. zsmalloc is also
> more actively developed and maintained, since it is the allocator of
> choice for zswap for many users, as well as the only allocator for zram.
>
> A historical objection to the selection of zsmalloc as the default
> allocator for zswap is its lack of writeback capability. However, this
> has changed, with the zsmalloc writeback patchset, and the subsequent
> zswap LRU refactor. With this, there is not a lot of good reasons to
> keep zbud, an otherwise inferior allocator, as the default instead of
> zswap.
>
> This patch changes the default allocator to zsmalloc. The only exception
> is on settings without MMU, in which case zbud will remain as the
> default.
>
> Signed-off-by: Nhat Pham <nphamcs@xxxxxxxxx>

Acked-by: Johannes Weiner <hannes@xxxxxxxxxxx>