On Wed, Nov 20, 2019 at 04:35:21AM +0000, Li Dongyang wrote: > For a bigalloc filesystem, converting the block bitmap from blocks > to chunks in ext2fs_convert_subcluster_bitmap() can take a long time > when the device is huge, because we test the bitmap > bit-by-bit using ext2fs_test_block_bitmap2(). > Use ext2fs_find_first_set_block_bitmap2() which is more efficient > for mke2fs when the fs is mostly empty. > > e2fsck can also benefit from this during pass1 block scanning. > > Time taken for "mke2fs -O bigalloc,extent -C 131072 -b 4096" on a 1PB > device: > > without patch: > real 27m49.457s > user 21m36.474s > sys 6m9.514s > > with patch: > real 6m31.908s > user 0m1.806s > sys 6m29.697s > > Signed-off-by: Li Dongyang <dongyangli@xxxxxxx> > Reviewed-by: Andreas Dilger <adilger@xxxxxxxxx> Applied, thanks. - Ted
