Andrew, References: <20101117035821.000579293@xxxxxxxxx> Content-Disposition: inline; filename=writeback-single-file-limit.patch This ensures full 4MB (or larger) writeback size for large dirty files. CC: Jan Kara <jack@xxxxxxx> Signed-off-by: Wu Fengguang <fengguang.wu@xxxxxxxxx> --- fs/fs-writeback.c | 11 +++++++++++ include/linux/writeback.h | 1 + 2 files changed, 12 insertions(+) --- linux-next.orig/fs/fs-writeback.c 2010-11-15 19:52:39.000000000 +0800 +++ linux-next/fs/fs-writeback.c 2010-11-15 21:31:50.000000000 +0800 @@ -330,6 +330,8 @@ static int writeback_single_inode(struct inode *inode, struct writeback_control *wbc) { struct address_space *mapping = inode->i_mapping; + long per_file_limit = wbc->per_file_limit; + long nr_to_write; unsigned dirty; int ret; @@ -365,8 +367,16 @@ writeback_single_inode(struct inode *ino inode->i_state &= ~I_DIRTY_PAGES; spin_unlock(&inode_lock); + if (per_file_limit) { + nr_to_write = wbc->nr_to_write; + wbc->nr_to_write = per_file_limit; + } + ret = do_writepages(mapping, wbc); + if (per_file_limit) + wbc->nr_to_write += nr_to_write - per_file_limit; + /* * Make sure to wait on the data before writing out the metadata. * This is important for filesystems that modify metadata on data @@ -698,6 +708,7 @@ static long wb_writeback(struct bdi_writ wbc.more_io = 0; wbc.nr_to_write = write_chunk; + wbc.per_file_limit = write_chunk; wbc.pages_skipped = 0; trace_wbc_writeback_start(&wbc, wb->bdi); --- linux-next.orig/include/linux/writeback.h 2010-11-15 19:52:39.000000000 +0800 +++ linux-next/include/linux/writeback.h 2010-11-15 21:31:50.000000000 +0800 @@ -43,6 +43,7 @@ struct writeback_control { extra jobs and livelock */ long nr_to_write; /* Write this many pages, and decrement this for each page written */ + long per_file_limit; /* Write this many pages for one file */ long pages_skipped; /* Pages which were not written */ /* -- 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