Subject: Re: [PATCH v2 7/7] gen_init_cpio: add -a <data_align> as reflink optimization

From: David Disseldorp <[email-masked]>
Date: Thu, 21 Aug 2025 18:10:56 +1000

Oops, I somehow missed this comment...

On Mon, 18 Aug 2025 21:23:36 +0200, Nicolas Schier wrote:
...
> Thanks!  Testing with a massively oversized initramfs (600MB) was fun:
> from 2:44 down to 38s.

Thanks for the benchmarking :)

> Questions that pop up in my mind:
> Now, how can we make other benefit from this?  Might it make sense to
> introduce a kconfig variable for initramfs alignment -- even though this
> is just a build-time optimisation of few seconds?

A kconfig option with non-aligned as default isn't a bad idea, but at
this stage I don't think it's worth adding. Mostly because reflinks are
very FS / arch / environment specific and the extra fragmentation may
have unintended consequences.

Thanks, David