Hi Jaegeuk, > -----Original Message----- > From: Jaegeuk Kim [mailto:jaegeuk@xxxxxxxxxx] > Sent: Sunday, January 24, 2016 4:16 AM > To: linux-kernel@xxxxxxxxxxxxxxx; linux-fsdevel@xxxxxxxxxxxxxxx; > linux-f2fs-devel@xxxxxxxxxxxxxxxxxxxxx > Cc: Jaegeuk Kim > Subject: [f2fs-dev] [PATCH 1/2] f2fs: avoid multiple node page writes due to inline_data > > The sceanrio is: > 1. create fully node blocks > 2. flush node blocks > 3. write inline_data for all the node blocks again > 4. flush node blocks redundantly > > Signed-off-by: Jaegeuk Kim <jaegeuk@xxxxxxxxxx> > --- > fs/f2fs/data.c | 14 +++++++++++--- > 1 file changed, 11 insertions(+), 3 deletions(-) > > diff --git a/fs/f2fs/data.c b/fs/f2fs/data.c > index 8d0d9ec..011456e 100644 > --- a/fs/f2fs/data.c > +++ b/fs/f2fs/data.c > @@ -1622,14 +1622,22 @@ static int f2fs_write_end(struct file *file, > > trace_f2fs_write_end(inode, pos, len, copied); > > - set_page_dirty(page); > - > if (pos + copied > i_size_read(inode)) { > i_size_write(inode, pos + copied); > mark_inode_dirty(inode); > - update_inode_page(inode); > } > > + if (f2fs_has_inline_data(inode) && > + is_inode_flag_set(F2FS_I(inode), FI_DATA_EXIST)) { > + int err = f2fs_write_inline_data(inode, page); Oh, I'm sure this can fix that issue, but IMO: a) this implementation has side-effect, it triggers inline data copying between data page and node page whenever user write inline datas, so if user updates inline data frequently, write-through approach would cause memory copy overhead. b) inline storm should be a rare case, as we didn't get any report about problem for long time until Dave's, and write_end is a hot path, I think it's better to be cautious to change our inline data cache policy for fixing a rare issue in hot path. What about delaying the merge operation? like: 1) as I proposed before, merging inline page into inode page when detecting free_sections <= (node_secs + 2 * dent_secs + inline_secs). 2) merge inline page into inode page before writeback inode page in sync_node_pages. Thanks, > + if (err) > + set_page_dirty(page); > + } else { > + set_page_dirty(page); > + } > + > + f2fs_write_inode(inode, NULL); > + > f2fs_put_page(page, 1); > f2fs_update_time(F2FS_I_SB(inode), REQ_TIME); > return copied; > -- > 2.6.3 > > > ------------------------------------------------------------------------------ > Site24x7 APM Insight: Get Deep Visibility into Application Performance > APM + Mobile APM + RUM: Monitor 3 App instances at just $35/Month > Monitor end-to-end web transactions and take corrective actions now > Troubleshoot faster and improve end-user experience. Signup Now! > http://pubads.g.doubleclick.net/gampad/clk?id=267308311&iu=/4140 > _______________________________________________ > Linux-f2fs-devel mailing list > Linux-f2fs-devel@xxxxxxxxxxxxxxxxxxxxx > https://lists.sourceforge.net/lists/listinfo/linux-f2fs-devel -- To unsubscribe from this list: send the line "unsubscribe linux-fsdevel" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
