On Fri, Jun 19, 2026 at 12:41 PM Ritesh Harjani (IBM) <[email protected]> wrote: > > THP_SWAP avoids splitting of a transparent huge folio into 32 smaller > 64K folios (Radix-64K pagesize / 2M PMD) or into 256 smaller 64K folios > (Hash-64K pagesize / 16M PMD), during swapout. This improves the > swapping performance since all the bookking & I/O submission happens > once per large folio. More details at [1]. > > PowerPC Book3S64 could not enable this before because PMD_ORDER is > selected at runtime depending upon the chosen MMU. The earlier patches > in this series turn SWAPFILE_CLUSTER into a runtime value and introduce > an ARCH_MAX_PMD_ORDER upperbound override for SWAP_NR_ORDERS. With those > changes, we can now enable THP SWAP for Book3S64. > > This increases bandwidth throughput with zram backend for swapout by > 40-50% with Radix and 100-130% with Hash (Tested by Sayali)
Thanks! I am curious about the contents of the anonymous memory being tested and the compression algorithm used by zram. > > [1]: https://lore.kernel.org/all/[email protected]/ Best Regards Barry
