On Sun, Apr 06, 2014 at 04:56:05PM +0400, Dmitry Monakhov wrote: > In worst case we need one extent per moved block. Number of blocks to > be moved is less or equals to blks_needed. I can believe that the original safety margin of 0.2% of how much we will be shrinking the file system might have been overly pessimistic. However I'm concerned that your change might be over-optimistic. For example, if we are shrinking the file system down to under 500 blocks, then the safety_margin will be 0 --- but it's could very easily be the case that an extent tree will need to grow. I'd accept this change, although I don't know it would make a difference in the cases you are concerned about: blk64_t safe_margin = (ext2fs_blocks_count(fs->super) - blks_needed)/500; if (safe_margin > blks_needed) safe_margin = blks_needed; How and why are you using this? I've never been all that exicited about the -M option, since it's been abused in so many different ways, and the result when you compress the file system that significantly is often no good for performance. - Ted -- 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
