From: Bobi Jam <bobijam.xu@xxxxxxxxx> When stride-RA hit case miss, we only reset normal sequential read-ahead window, but not reset the stride IO to avoid the overhead of re-detecting stride IO. While when the normal RA window is set to not insect with the stride-RA window, when we try to increase the stride-RA window length later, the presumption does not hold. This patch resets the stride IO as well in this case. Signed-off-by: Bobi Jam <bobijam.xu@xxxxxxxxx> Reviewed-on: http://review.whamcloud.com/23032 Intel-bug-id: https://jira.hpdd.intel.com/browse/LU-8683 Reviewed-by: wangdi <di.wang@xxxxxxxxx> Reviewed-by: Jinshan Xiong <jinshan.xiong@xxxxxxxxx> Signed-off-by: Oleg Drokin <green@xxxxxxxxxxxxxx> --- drivers/staging/lustre/lustre/llite/rw.c | 15 +++++++++++---- 1 file changed, 11 insertions(+), 4 deletions(-) diff --git a/drivers/staging/lustre/lustre/llite/rw.c b/drivers/staging/lustre/lustre/llite/rw.c index d2515a8..e34017d 100644 --- a/drivers/staging/lustre/lustre/llite/rw.c +++ b/drivers/staging/lustre/lustre/llite/rw.c @@ -809,13 +809,20 @@ static void ras_update(struct ll_sb_info *sbi, struct inode *inode, if (ra_miss) { if (index_in_stride_window(ras, index) && stride_io_mode(ras)) { - /*If stride-RA hit cache miss, the stride dector - *will not be reset to avoid the overhead of - *redetecting read-ahead mode - */ if (index != ras->ras_last_readpage + 1) ras->ras_consecutive_pages = 0; ras_reset(inode, ras, index); + + /* If stride-RA hit cache miss, the stride + * detector will not be reset to avoid the + * overhead of redetecting read-ahead mode, + * but on the condition that the stride window + * is still intersect with normal sequential + * read-ahead window. + */ + if (ras->ras_window_start < + ras->ras_stride_offset) + ras_stride_reset(ras); RAS_CDEBUG(ras); } else { /* Reset both stride window and normal RA -- 2.7.4 _______________________________________________ devel mailing list devel@xxxxxxxxxxxxxxxxxxxxxx http://driverdev.linuxdriverproject.org/mailman/listinfo/driverdev-devel
