On Mon, Jun 15, 2015 at 5:05 PM, Rik van Riel <riel@xxxxxxxxxx> wrote: > > On 06/14/2015 11:04 AM, Ebru Akagunduz wrote: > > This patch makes optimistic check for swapin readahead > > to increase thp collapse rate. Before getting swapped > > out pages to memory, checks them and allows up to a > > certain number. It also prints out using tracepoints > > amount of unmapped ptes. > > > > Signed-off-by: Ebru Akagunduz <ebru.akagunduz@xxxxxxxxx> > > > @@ -2639,11 +2640,11 @@ static int khugepaged_scan_pmd(struct mm_struct *mm, > > { > > pmd_t *pmd; > > pte_t *pte, *_pte; > > - int ret = 0, none_or_zero = 0; > > + int ret = 0, none_or_zero = 0, unmapped = 0; > > struct page *page; > > unsigned long _address; > > spinlock_t *ptl; > > - int node = NUMA_NO_NODE; > > + int node = NUMA_NO_NODE, max_ptes_swap = HPAGE_PMD_NR/8; > > bool writable = false, referenced = false; > > This has the effect of only swapping in 4kB pages to form a THP > if 7/8th of the THP is already resident in memory. Thanks for clarifing it to me. -- 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>