Question Understanding key_bytes in node status

Checked under man file cockroach-node-status.1, but it only describes options, and not the output. Is it documented somewhere (in the included docs or online?)

My main question is key_bytes, and why is it negative on some nodes?

id address build updated_at started_at live_bytes key_bytes value_bytes intent_bytes system_bytes replicas_leaders replicas_leaseholders ranges ranges_unavailable ranges_underreplicated
1 crdb1a.ces.cvnt.net:26257 v1.0-rc.1-dirty 2017-05-06 15:55:51 2017-05-06 00:11:51 422022178 188412969 233609209 0 13766 4 4 4 0 0
2 crdb2a.ces.cvnt.net:26257 v1.0-rc.1-dirty 2017-05-06 15:55:57 2017-05-06 00:12:17 337063021 162434702 174628319 0 12934 4 4 4 0 0
3 crdb3a.ces.cvnt.net:26257 v1.0-rc.1-dirty 2017-05-06 15:55:57 2017-05-06 00:12:27 269184403 194453326 74731077 0 13850 4 4 4 0 0
4 crdb4a.ces.cvnt.net:26257 v1.0-rc.1-dirty 2017-05-06 15:55:53 2017-05-06 00:12:33 146290742 1915603 149584223 0 17070 3 3 3 0 0
5 crdb5a.ces.cvnt.net:26257 v1.0-rc.1-dirty 2017-05-06 15:56:00 2017-05-06 00:12:40 496369685 1165852 500370176 0 18631 3 3 3 0 0
6 crdb1c.ces.cvnt.net:26257 v1.0-rc.1-dirty 2017-05-06 15:56:00 2017-05-06 00:13:10 701141659 -590324 701731983 0 17418 4 4 4 0 0
7 crdb1d.ces.cvnt.net:26257 v1.0-rc.1-dirty 2017-05-06 15:55:52 2017-05-06 00:51:55 564495313 -849666 565361979 0 16173 3 3 3 0 0
8 crdb1e.ces.cvnt.net:26257 v1.0-rc.1-dirty 2017-05-06 15:55:58 2017-05-06 00:52:48 348689567 6467692 342248281 0 17212 4 3 4 0 0
9 crdb1f.ces.cvnt.net:26257 v1.0-rc.1-dirty 2017-05-06 15:55:56 2017-05-06 00:53:16 373704196 893357 372837245 0 19178 3 3 3 0 0
10 crdb1h.ces.cvnt.net:26257 v1.0-rc.1-dirty 2017-05-06 15:55:56 2017-05-06 00:54:46 464299633 32346476 431970157 0 19565 4 4 4 0 0
11 crdb2h.ces.cvnt.net:26257 v1.0-rc.1-dirty 2017-05-06 15:55:59 2017-05-06 00:57:19 248626560 157678 248468882 0 16422 3 3 3 0 0
12 crdb3h.ces.cvnt.net:26257 v1.0-rc.1-dirty 2017-05-06 15:55:56 2017-05-06 00:57:25 265149565 1938700 268376788 0 16090 4 4 4 0 0

(Relatively fresh install with some imported test data).

key_bytes and value_bytes are the amount of data in the underlying key-value store. These fields are sometimes estimates; they can slip out of sync until the next full scan recomputes the real values. However, I’m surprised that they would get so far out of sync that the total key_bytes for a node would become negative (especially while value_bytes is so large)