Re: [PATCH 0/2] mm,swap: skip swap readahead for instant IO (like zswap)

[Andrew Morton]

On Mon, 21 Sep 2020 22:01:46 -0400 Rik van Riel <riel@xxxxxxxxxxx> wrote:

> Both with frontswap/zswap, and with some extremely fast IO devices,
> swap IO will be done before the "asynchronous" swap_readpage() call
> has returned.
> 
> In that case, doing swap readahead only wastes memory, increases
> latency, and increases the chances of needing to evict something more
> useful from memory. In that case, just skip swap readahead.

Any quantitative testing results?