Re: [PATCH RFC 1/2] mm: meminit: initialise more memory for inode/dentry hash tables in early boot
From: Anshuman Khandual <hidden>
Date: 2016-03-03 09:41:23
Also in:
linux-mm, lkml
On 03/03/2016 12:31 PM, Li Zhang wrote:
From: Li Zhang <redacted> 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
Typo here ....................................^^^^^^^^
fixed with a completion to wait for all memory initialised in page_alloc_init_late(). It is to fix the oom problem on X86
You can just write *out of memory* instead of *oom* or put them in capitals.
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
I am wondering how its going to impact other architectures.
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:The dmesg output here needs some formatting.
quoted hunk ↗ jump to hunk
Signed-off-by: Li Zhang <redacted> --- 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) &&
Does this change need to be tested on all architectures ?