On Thu, Jun 21, 2018 at 3:17 AM, Ming Lei <ming.lei@xxxxxxxxxx> wrote: > On Fri, Jun 15, 2018 at 02:59:19PM +0200, Gi-Oh Kim wrote: >> > >> > - bio size can be increased and it should improve some high-bandwidth IO >> > case in theory[4]. >> > >> >> Hi, >> >> I would like to report your patch set works well on my system based on v4.14.48. >> I thought the multipage bvec could improve the performance of my system. >> (FYI, my system has v4.14.48 and provides KVM-base virtualization service.) > > Thanks for your test! > >> >> So I did back-porting your patches to v4.14.48. >> It has done without any serious problem. >> I only needed to cherry-pick "blk-merge: compute >> bio->bi_seg_front_size efficiently" and >> "block: move bio_alloc_pages() to bcache" patches before back-porting >> to prevent conflicts. > > Not sure I understand your point, you have to backport all patches. Never mind. I just meant I did backporting for myself and it is still working well. > > At least now, BIO_MAX_PAGES can be fixed as 256 in case of CONFIG_THP_SWAP, > otherwise 2 pages may be allocated for holding the bvec table, so tests > in case of THP_SWAP may be improved. > > Also filesystem may support IO to/from THP, and multipage bvec should > improve this case too. OK, I got it. I will find something to use THP_SWAP and run the performance test with it. Thank you ;-) -- GIOH KIM Linux Kernel Entwickler ProfitBricks GmbH Greifswalder Str. 207 D - 10405 Berlin Tel: +49 176 2697 8962 Fax: +49 30 577 008 299 Email: gi-oh.kim@xxxxxxxxxxxxxxxx URL: https://www.profitbricks.de Sitz der Gesellschaft: Berlin Registergericht: Amtsgericht Charlottenburg, HRB 125506 B Geschäftsführer: Achim Weiss, Matthias Steinberg, Christoph Steffens