2016-03-18 6:45 GMT+08:00 Eric Wheeler <dm-devel@xxxxxxxxxxxxxxxxxx>: > > On Thu, 17 Mar 2016, Joe Thornber wrote: > >> If you're skipping the mappings does the new thin_ls provide enough >> information for you? > > Our primary need is the ability to specify --device-id in the o:L:d output > format (old_format.cc) with mappings. Our nightly dumps now take 50 > seconds instead of 40 minutes since we only dump the dev_id's that we > need. > I have similar requirement. I did this by my own compact_emitter, which is a simplified version of "human_readable_emitter", without showing the arrows and parentheses: output format: begin superblock=>uuid:"",time:<time>,transaction:<tid>,flags:<flags>,version:<version>,data_block_size:<bs>,nr_data_blocks:<nr_blocks> device=>dev_id:<dev_id>,mapped_blocks:<mapped_blocks>,transaction:<tid>,creation_time:<creation_time>,snap_time:<snap_time> <origin_begin>,<data_begin>,<len>,<time> <origin_begin>,<data_begin>,1,<time> ... end superblock e.g., begin superblock=>uuid:"",time:0,transaction:1,flags:0,version:1,data_block_size:2048,nr_data_blocks:5657156 device=>dev_id:10000,mapped_blocks:3864041,transaction:0,creation_time:0,snap_time:0 1000,2000,100,0 1100,3000,200,0 ... end superblock The <time> field is preserved for snapshot comparison. Maybe we could discuss on creating a flexible emitter that could customize the output format: - Mapping units: sectors or blocks - Emit the superblock and device tags or not. I think that an end mark might be better for network transmission, to determine whether the dump was ended or not. - Other consideration: should the customized output compatible to thin_restore ? Ming-Hung Tsai -- dm-devel mailing list dm-devel@xxxxxxxxxx https://www.redhat.com/mailman/listinfo/dm-devel
