On 03/24/2014 05:58 AM, Wang Shilong wrote:
To compress a small write(<=blocksize) dosen't save us disk space at all, skip it can save us some compression time. This patch can also fix wrong setting nocompression flag for inode, say a case when @total_in is 4096, and then we get @total_compressed 52,because we do aligment to page cache size firstly, and then we get into conclusion @total_in=@total_compressed thus we will clear this inode's compression flag. An exception comes from inserting inline extent failure but we still have @total_compressed < @total_in,so we will still reset inode's flag, this is ok, because we don't have good compression effect.
So your check for start > 0 || end + 1 < disk_i_size means we're only skipping compression for a small file range that isn't in an inline extent. Could you please update the patch description and comments in the code to reflect this?
Thanks! -chris -- To unsubscribe from this list: send the line "unsubscribe linux-btrfs" in the body of a message to [email protected] More majordomo info at http://vger.kernel.org/majordomo-info.html
