Re: [PATCH v7 0/6] Implement writeback for zsmalloc

[Thomas Weißschuh]

Hi,

On Mon, Nov 28, 2022 at 11:16:09AM -0800, Nhat Pham wrote:
> Unlike other zswap's allocators such as zbud or z3fold, zsmalloc
> currently lacks the writeback mechanism. This means that when the zswap
> pool is full, it will simply reject further allocations, and the pages
> will be written directly to swap.
> 
> This series of patches implements writeback for zsmalloc. When the zswap
> pool becomes full, zsmalloc will attempt to evict all the compressed
> objects in the least-recently used zspages.

Then this part of Documentation/admin-guide/mm/zswap.rst should probably
also be updated at some point:

    However, zsmalloc does not implement compressed page eviction, so
    once zswap fills it cannot evict the oldest page, it can only reject
    new pages.

Thomas