Always "Breaking from mining"

[ethers]

develop ac473a8

Ran Geth with mining (and default logging level). For over 30 minutes, the only logs are "Breaking from mining" except for the occasional [P2P NAT] mapping error: no devices discovered
Is Geth actually doing some mining, or it's unable to because new blocks are being produced too quickly?

2015/04/04 18:05:08 [POW] Making Cache
2015/04/04 18:05:09 [POW] Took: 1.089541915s
2015/04/04 18:05:09 [POW] Retrieving DAG
2015/04/04 18:05:10 [POW] Took: 837.225652ms
2015/04/04 18:05:11 [POW] Breaking from mining
2015/04/04 18:05:11 [POW] Breaking from mining
2015/04/04 18:05:11 [POW] Breaking from mining
2015/04/04 18:05:22 [POW] Breaking from mining
2015/04/04 18:05:22 [POW] Breaking from mining
and so on
2015/04/04 18:29:57 [POW] Breaking from mining
2015/04/04 18:29:57 [POW] Breaking from mining

[obscuren]

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