From: Li Zhang <zhlcindy@xxxxxxxxxxxxxxxxxx> This patch is based on Mel Gorman's old patch in the mailing list, https://lkml.org/lkml/2015/5/5/280 which is dicussed but it is fixed with a completion to wait for all memory initialised in page_alloc_init_late(). It is to fix the oom problem on X86 with 24TB memory which allocates memory in late initialisation. But for Power platform with 32TB memory, it causes a call trace in vfs_caches_init->inode_init() and inode hash table needs more memory. So this patch allocates 1GB for 0.25TB/node for large system as it is mentioned in https://lkml.org/lkml/2015/5/1/627 This call trace is found on Power with 32TB memory, 1024CPUs, 16nodes. The log from dmesg as the following: [ 0.091780] Dentry cache hash table entries: 2147483648 (order: 18, 17179869184 bytes) [ 2.891012] vmalloc: allocation failure, allocated 16021913600 of 17179934720 bytes [ 2.891034] swapper/0: page allocation failure: order:0, mode:0x2080020 [ 2.891038] CPU: 0 PID: 0 Comm: swapper/0 Not tainted 4.4.0-0-ppc64 [ 2.891041] Call Trace: [ 2.891046] [c0000000012bfa00] [c0000000007c4a50] .dump_stack+0xb4/0xb664 (unreliable) [ 2.891051] [c0000000012bfa80] [c0000000001f93d4] .warn_alloc_failed+0x114/0x160 [ 2.891054] [c0000000012bfb30] [c00000000023c204] .__vmalloc_area_node+0x1a4/0x2b0 [ 2.891058] [c0000000012bfbf0] [c00000000023c3f4] .__vmalloc_node_range+0xe4/0x110 [ 2.891061] [c0000000012bfc90] [c00000000023c460] .__vmalloc_node+0x40/0x50 [ 2.891065] [c0000000012bfd10] [c000000000b67d60] .alloc_large_system_hash+0x134/0x2a4 [ 2.891068] [c0000000012bfdd0] [c000000000b70924] .inode_init+0xa4/0xf0 [ 2.891071] [c0000000012bfe60] [c000000000b706a0] .vfs_caches_init+0x80/0x144 [ 2.891074] [c0000000012bfef0] [c000000000b35208] .start_kernel+0x40c/0x4e0 [ 2.891078] [c0000000012bff90] [c000000000008cfc] start_here_common+0x20/0x4a4 [ 2.891080] Mem-Info: Signed-off-by: Li Zhang <zhlcindy@xxxxxxxxxxxxxxxxxx> --- mm/page_alloc.c | 11 +++++++++-- 1 file changed, 9 insertions(+), 2 deletions(-) diff --git a/mm/page_alloc.c b/mm/page_alloc.c index 838ca8bb..4847f25 100644 --- a/mm/page_alloc.c +++ b/mm/page_alloc.c @@ -293,13 +293,20 @@ static inline bool update_defer_init(pg_data_t *pgdat, unsigned long pfn, unsigned long zone_end, unsigned long *nr_initialised) { + unsigned long max_initialise; + /* Always populate low zones for address-contrained allocations */ if (zone_end < pgdat_end_pfn(pgdat)) return true; + /* + * Initialise at least 2G of a node but also take into account that + * two large system hashes that can take up 1GB for 0.25TB/node. + */ + max_initialise = max(2UL << (30 - PAGE_SHIFT), + (pgdat->node_spanned_pages >> 8)); - /* Initialise at least 2G of the highest zone */ (*nr_initialised)++; - if (*nr_initialised > (2UL << (30 - PAGE_SHIFT)) && + if ((*nr_initialised > max_initialise) && (pfn & (PAGES_PER_SECTION - 1)) == 0) { pgdat->first_deferred_pfn = pfn; return false; -- 2.1.0 -- 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>