From: Pavel Tatashin <pasha.tatashin@xxxxxxxxxx> Date: Mon, 28 Aug 2017 22:02:18 -0400 > Add an optimized mm_zero_struct_page(), so struct page's are zeroed without > calling memset(). We do eight to ten regular stores based on the size of > struct page. Compiler optimizes out the conditions of switch() statement. > > SPARC-M6 with 15T of memory, single thread performance: > > BASE FIX OPTIMIZED_FIX > bootmem_init 28.440467985s 2.305674818s 2.305161615s > free_area_init_nodes 202.845901673s 225.343084508s 172.556506560s > -------------------------------------------- > Total 231.286369658s 227.648759326s 174.861668175s > > BASE: current linux > FIX: This patch series without "optimized struct page zeroing" > OPTIMIZED_FIX: This patch series including the current patch. > > bootmem_init() is where memory for struct pages is zeroed during > allocation. Note, about two seconds in this function is a fixed time: it > does not increase as memory is increased. > > Signed-off-by: Pavel Tatashin <pasha.tatashin@xxxxxxxxxx> > Reviewed-by: Steven Sistare <steven.sistare@xxxxxxxxxx> > Reviewed-by: Daniel Jordan <daniel.m.jordan@xxxxxxxxxx> > Reviewed-by: Bob Picco <bob.picco@xxxxxxxxxx> You should probably use initializing stores when you are doing 8 stores and we thus know the page struct is cache line aligned. But other than that: Acked-by: David S. Miller <davem@xxxxxxxxxxxxx> -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@xxxxxxxxx. For more info on Linux MM, see: http://www.linux-mm.org/ . Don't email: <a href=mailto:"dont@xxxxxxxxx";> email@xxxxxxxxx </a>
