From 09c231cb8bfdc35e7d896850d34440b8553b084f Mon Sep 17 00:00:00 2001 From: Nathan Zimmer Date: Tue, 31 Jul 2012 16:46:17 -0700 Subject: tmpfs: distribute interleave better across nodes When tmpfs has the interleave memory policy, it always starts allocating for each file from node 0 at offset 0. When there are many small files, the lower nodes fill up disproportionately. This patch spreads out node usage by starting files at nodes other than 0, by using the inode number to bias the starting node for interleave. Signed-off-by: Nathan Zimmer Signed-off-by: Hugh Dickins Cc: Christoph Lameter Cc: Nick Piggin Cc: Lee Schermerhorn Cc: KOSAKI Motohiro Cc: Rik van Riel Cc: Andi Kleen Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- mm/shmem.c | 6 ++++-- 1 file changed, 4 insertions(+), 2 deletions(-) (limited to 'mm') diff --git a/mm/shmem.c b/mm/shmem.c index c15b998e5a86..d4e184e2a38e 100644 --- a/mm/shmem.c +++ b/mm/shmem.c @@ -929,7 +929,8 @@ static struct page *shmem_swapin(swp_entry_t swap, gfp_t gfp, /* Create a pseudo vma that just contains the policy */ pvma.vm_start = 0; - pvma.vm_pgoff = index; + /* Bias interleave by inode number to distribute better across nodes */ + pvma.vm_pgoff = index + info->vfs_inode.i_ino; pvma.vm_ops = NULL; pvma.vm_policy = spol; return swapin_readahead(swap, gfp, &pvma, 0); @@ -942,7 +943,8 @@ static struct page *shmem_alloc_page(gfp_t gfp, /* Create a pseudo vma that just contains the policy */ pvma.vm_start = 0; - pvma.vm_pgoff = index; + /* Bias interleave by inode number to distribute better across nodes */ + pvma.vm_pgoff = index + info->vfs_inode.i_ino; pvma.vm_ops = NULL; pvma.vm_policy = mpol_shared_policy_lookup(&info->policy, index); -- cgit v1.2.3