On 2011-11-19, at 2:57, Yongqiang Yang <xiaoqiangnk@xxxxxxxxx> wrote: > This patch series adds new resize implementation to ext4. > > -- What's new resize implementation? > It is a new online resize interface for ext4. It can be used via > ioctl with EXT4_IOC_RESIZE_FS and a 64 bit integer indicating size > of the resized fs in block. > > -- Difference between current resize and new resize. > New resize lets kernel do all work, like allocating bitmaps and > inode tables and can support flex_bg and BLOCK_UNINIT features. > Besides these, new resize is much faster than current resize. > > Below are benchmarks I made on my personal computer, fses with > flex_bg size = 16 were resized to 230GB evry time. The first > row shows the size of a fs from which the fs was resized to 230GB. > The datas were collected by 'time resize2fs'. > > new resize > 20GB 50GB 100GB > real 0m3.558s 0m2.891s 0m0.394s > user 0m0.004s 0m0.000s 0m0.394s > sys 0m0.048s 0m0.048s 0m0.028s > > current resize > 20GB 50GB 100GB > real 5m2.770s 4m43.757s 3m14.840s > user 0m0.040s 0m0.032s 0m0.024s > sys 0m0.464s 0m0.432s 0m0.324s These stats must be backward, because resizing 20GB takes more time than resizing 100GB. > According to data above, new resize is faster than current resize in both > user and sys time. New resize performs well in sys time, because it > supports BLOCK_UNINIT and adds multi-groups each time. > > -- About supporting new features. > YES! New resize can support new feature like bigalloc and exclude bitmap > easily. Because it lets kernel do all work. > > V3->V4: > rename __ext4_group_extend to ext4_group_extend_no_check. > > V2->V3: > initialize block bitmap of last group. > remove code initalizing inode bitmap and inode tables. > > Yongqiang. > > git diff --stat > > Documentation/filesystems/ext4.txt | 7 + > fs/ext4/ext4.h | 10 + > fs/ext4/ioctl.c | 39 ++ > fs/ext4/resize.c | 1167 +++++++++++++++++++++++++++--------- > 4 files changed, 942 insertions(+), 281 deletions(-) > > -- To unsubscribe from this list: send the line "unsubscribe linux-ext4" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
