Re: [PATCH v6 00/12] Virtual Swap Space (Swap Table Edition)

[Gregory Price (Meta)]

On 2026-10-20 23:03 -0700, Nhat Pham wrote:
> B. Semi-synthetic Workloads (memhog, usemem, kernel build)
> ==========================================================
> 
> All values are mean +/- standard deviation across rounds.
> 
> Test system: x86_64, 52 cores, 64 GB swapfile for all 3 benchmarks.
> Swap backend: zswap (zstd) with the traditional active/inactive LRU. We
> focus on zswap here because it is the motivating use case for vswap.
>

I get that the motivation is zswap, but it would be nice to have
disk-swap performance numbers here as well right in the cover.

If only because...

> For each benchmark, we test 3 kernels:
> * Baseline: mm-unstable, no vswap patches.
> * VSS off: vswap series applied, vswap=off, to verify that there is no
>   regression to existing swap paths when we disable vswap.
> * VSS on: vswap series applied, vswap=on.
> 

If the numbers you presented carry through, I'm left wondering why this
is a boot option and not a build option.  I rather dislike the boot
option compromise in general - but other reasoning aside, if there's no
performance impact, then I don't see why it shouldn't be the default.

~Gregory

-- 
Gregory Price (Meta) <gourry@xxxxxxxxxx>