Re: [RFC PATCH 4/5] mm: truncate: split huge page cache page to a non-zero order if possible.

[Roman Gushchin]

On Mon, Mar 21, 2022 at 10:21:27AM -0400, Zi Yan wrote:
> From: Zi Yan <ziy@xxxxxxxxxx>
> 
> To minimize the number of pages after a huge page truncation, we do not
> need to split it all the way down to order-0. The huge page has at most
> three parts, the part before offset, the part to be truncated, the part
> remaining at the end. Find the greatest common power of two multiplier of
> the non-zero values of them as the new order, so we can split the huge
> page to this order and keep the remaining pages as large and as few as
> possible.

Would you mind please to describe the algorithm in more details?

Thanks!