From: Yuezhang Mo <Yuezhang.Mo@xxxxxxxx> This patch set changes sync dentry-by-dentry to sync dentrySet-by-dentrySet, and remove some syncs that do not cause data loss. It not only improves the performance of sync dentry, but also reduces the consumption of storage device life. I used the following commands and blktrace to measure the improvements on a class 10 SDXC card. rm -fr $mnt/dir; mkdir $mnt/dir; sync time (for ((i=0;i<1000;i++));do touch $mnt/dir/${prefix}$i;done;sync $mnt) time (for ((i=0;i<1000;i++));do rm $mnt/dir/${prefix}$i;done;sync $mnt) | case | name len | create | unlink | | | | time | write size | time | write size | |------+----------+----------+------------+-----------+------------| | 1 | 15 | 10.260s | 191KiB | 9.829s | 96KiB | | 2 | 15 | 11.456s | 562KiB | 11.032s | 562KiB | | 3 | 15 | 30.637s | 3500KiB | 21.740s | 2000KiB | | 1 | 120 | 10.840s | 644KiB | 9.961s | 315KiB | | 2 | 120 | 13.282s | 1092KiB | 12.432s | 752KiB | | 3 | 120 | 45.393s | 7573KiB | 37.395s | 5500KiB | | 1 | 255 | 11.549s | 1028KiB | 9.994s | 594KiB | | 2 | 255 | 15.826s | 2170KiB | 13.387s | 1063KiB | | 3 | 255 | 1m7.211s | 12335KiB | 0m58.517s | 10004KiB | case 1. disable dirsync case 2. with this patch set and enable dirsync case 3. without this patch set and enable dirsync Yuezhang Mo (11): exfat: add __exfat_get_dentry_set() helper exfat: add exfat_get_empty_dentry_set() helper exfat: covert exfat_find_empty_entry() to use dentry cache exfat: covert exfat_add_entry() to use dentry cache exfat: covert exfat_remove_entries() to use dentry cache exfat: move free cluster out of exfat_init_ext_entry() exfat: covert exfat_init_ext_entry() to use dentry cache exfat: remove __exfat_find_empty_entry() exfat: remove unused functions exfat: do not sync parent dir if just update timestamp exfat: remove duplicate update parent dir fs/exfat/dir.c | 286 ++++++++++++++++++----------------- fs/exfat/exfat_fs.h | 23 ++- fs/exfat/inode.c | 2 +- fs/exfat/namei.c | 352 +++++++++++++++++--------------------------- 4 files changed, 288 insertions(+), 375 deletions(-) -- 2.25.1