[PATCH] Docs/admin-guide/mm/zswap: remove zsmalloc's lack of writeback warning

[PATCH] Docs/admin-guide/mm/zswap: remove zsmalloc's lack of writeback warning

[Nhat Pham]

Writeback has been implemented for zsmalloc, so this warning no longer
holds.

Suggested-by: Thomas Weißschuh <linux@weissschuh.net>
Signed-off-by: Nhat Pham <nphamcs@gmail.com>
---
 Documentation/admin-guide/mm/zswap.rst | 4 +---
 1 file changed, 1 insertion(+), 3 deletions(-)

diff --git a/Documentation/admin-guide/mm/zswap.rst b/Documentation/admin-guide/mm/zswap.rst
index f67de481c7f6..6dd74a18268b 100644
--- a/Documentation/admin-guide/mm/zswap.rst
+++ b/Documentation/admin-guide/mm/zswap.rst
@@ -70,9 +70,7 @@ e.g. ``zswap.zpool=zbud``. It can also be changed at runtime using the sysfs
 The zbud type zpool allocates exactly 1 page to store 2 compressed pages, which
 means the compression ratio will always be 2:1 or worse (because of half-full
 zbud pages).  The zsmalloc type zpool has a more complex compressed page
-storage method, and it can achieve greater storage densities.  However,
-zsmalloc does not implement compressed page eviction, so once zswap fills it
-cannot evict the oldest page, it can only reject new pages.
+storage method, and it can achieve greater storage densities.
 
 When a swap page is passed from frontswap to zswap, zswap maintains a mapping
 of the swap entry, a combination of the swap type and swap offset, to the zpool
-- 
2.30.2

Re: [PATCH] Docs/admin-guide/mm/zswap: remove zsmalloc's lack of writeback warning

[Nhat Pham]

On Fri, Jan 6, 2023 at 2:00 PM Nhat Pham <nphamcs@gmail.com> wrote:
>
> Writeback has been implemented for zsmalloc, so this warning no longer
> holds.
>
> Suggested-by: Thomas Weißschuh <linux@weissschuh.net>
> Signed-off-by: Nhat Pham <nphamcs@gmail.com>
> ---
>  Documentation/admin-guide/mm/zswap.rst | 4 +---
>  1 file changed, 1 insertion(+), 3 deletions(-)
>
> diff --git a/Documentation/admin-guide/mm/zswap.rst b/Documentation/admin-guide/mm/zswap.rst
> index f67de481c7f6..6dd74a18268b 100644
> --- a/Documentation/admin-guide/mm/zswap.rst
> +++ b/Documentation/admin-guide/mm/zswap.rst
> @@ -70,9 +70,7 @@ e.g. ``zswap.zpool=zbud``. It can also be changed at runtime using the sysfs
>  The zbud type zpool allocates exactly 1 page to store 2 compressed pages, which
>  means the compression ratio will always be 2:1 or worse (because of half-full
>  zbud pages).  The zsmalloc type zpool has a more complex compressed page
> -storage method, and it can achieve greater storage densities.  However,
> -zsmalloc does not implement compressed page eviction, so once zswap fills it
> -cannot evict the oldest page, it can only reject new pages.
> +storage method, and it can achieve greater storage densities.
>
>  When a swap page is passed from frontswap to zswap, zswap maintains a mapping
>  of the swap entry, a combination of the swap type and swap offset, to the zpool
> --
> 2.30.2
>

Link to the patch series:
https://lkml.org/lkml/2022/11/28/1140

And the suggestion:
https://lkml.org/lkml/2023/1/2/823

Re: [PATCH] Docs/admin-guide/mm/zswap: remove zsmalloc's lack of writeback warning

[Jonathan Corbet]

Nhat Pham <nphamcs@gmail.com> writes:

> Writeback has been implemented for zsmalloc, so this warning no longer
> holds.
>
> Suggested-by: Thomas Weißschuh <linux@weissschuh.net>
> Signed-off-by: Nhat Pham <nphamcs@gmail.com>
> ---
>  Documentation/admin-guide/mm/zswap.rst | 4 +---
>  1 file changed, 1 insertion(+), 3 deletions(-)
>
> diff --git a/Documentation/admin-guide/mm/zswap.rst b/Documentation/admin-guide/mm/zswap.rst
> index f67de481c7f6..6dd74a18268b 100644
> --- a/Documentation/admin-guide/mm/zswap.rst
> +++ b/Documentation/admin-guide/mm/zswap.rst
> @@ -70,9 +70,7 @@ e.g. ``zswap.zpool=zbud``. It can also be changed at runtime using the sysfs
>  The zbud type zpool allocates exactly 1 page to store 2 compressed pages, which
>  means the compression ratio will always be 2:1 or worse (because of half-full
>  zbud pages).  The zsmalloc type zpool has a more complex compressed page
> -storage method, and it can achieve greater storage densities.  However,
> -zsmalloc does not implement compressed page eviction, so once zswap fills it
> -cannot evict the oldest page, it can only reject new pages.
> +storage method, and it can achieve greater storage densities.
>  

Applied, thanks.

jon