[BUG] Occasionally, pmc stuck.

[LimHyungTae]

In submap-level scale registration, I sometimes observe some weird stop, and output below information from pmc.

[pmc: thread 1
[pmc: bounds updated - thread 1] time = 6.76057 sec, |V| = 2578 (688 / 3266), |E| = 1789816, w = 418, p = 0.33569, d_min = 3, d_avg = 1148.78, d_max = 2000, k_max = 1066
[pmc: bounds updated - thread 7] time = 10.0177 sec, |V| = 2451 (815 / 3266), |E| = 1789816, w = 419, p = 0.33569, d_min = 3, d_avg = 1148.78, d_max = 2000, k_max = 1066
[pmc: bounds updated - thread 6] time = 10.1777 sec, |V| = 2534 (732 / 3266), |E| = 1789816, w = 419, p = 0.33569, d_min = 3, d_avg = 1148.78, d_max = 2000, k_max = 1066
[pmc: bounds updated - thread 8] time = 16.273 sec, |V| = 2498 (768 / 3266), |E| = 1789816, w = 419, p = 0.33569, d_min = 3, d_avg = 1148.78, d_max = 2000, k_max = 1066
[pmc: bounds updated - thread 2] time = 39.552 sec, |V| = 2475 (791 / 3266), |E| = 1789816, w = 424, p = 0.33569, d_min = 3, d_avg = 1148.78, d_max = 2000, k_max = 1066
[pmc: bounds updated - thread 11] time = 42.0549 sec, |V| = 2593 (673 / 3266), |E| = 1789816, w = 424, p = 0.33569, d_min = 3, d_avg = 1148.78, d_max = 2000, k_max = 1066
[pmc: bounds updated - thread 9] time = 49.9065 sec, |V| = 2457 (809 / 3266), |E| = 1789816, w = 424, p = 0.33569, d_min = 3, d_avg = 1148.78, d_max = 2000, k_max = 1066
[pmc: thread 2]
[pmc: bounds updated - thread 2] time = 53.0678 sec, |V| = 2446 (820 / 3266), |E| = 1789816, w = 424, p = 0.33569, d_min = 3, d_avg = 1148.78, d_max = 2000, k_max = 1066
[pmc: bounds updated - thread 3] time = 67.9128 sec, |V| = 2544 (722 / 3266), |E| = 1789816, w = 424, p = 0.33569, d_min = 3, d_avg = 1148.78, d_max = 2000, k_max = 1066
[pmc: bounds updated - thread 10] time = 90.05 sec, |V| = 2459 (807 / 3266), |E| = 1789816, w = 427, p = 0.33569, d_min = 3, d_avg = 1148.78, d_max = 2000, k_max = 1066
[pmc: bounds updated - thread 8] time = 93.8862 sec, |V| = 2447 (819 / 3266), |E| = 1789816, w = 427, p = 0.33569, d_min = 3, d_avg = 1148.78, d_max = 2000, k_max = 1066
[pmc: bounds updated - thread 4] time = 99.2371 sec, |V| = 2501 (765 / 3266), |E| = 1789816, w = 429, p = 0.33569, d_min = 3, d_avg = 1148.78, d_max = 2000, k_max = 1066
[pmc: bounds updated - thread 5] time = 99.5337 sec, |V| = 2465 (801 / 3266), |E| = 1789816, w = 433, p = 0.33569, d_min = 3, d_avg = 1148.78, d_max = 2000, k_max = 1066
[pmc: bounds updated - thread 6] time = 99.6294 sec, |V| = 2448 (818 / 3266), |E| = 1789816, w = 433, p = 0.33569, d_min = 3, d_avg = 1148.78, d_max = 2000, k_max = 1066
[pmc: thread 2]
[pmc: bounds updated - thread 2] time = 101.602 sec, |V| = 2423 (843 / 3266), |E| = 1789816, w = 434, p = 0.33569, d_min = 3, d_avg = 1148.78, d_max = 2000, k_max = 1066
[pmc: bounds updated - thread 12] time = 103.001 sec, |V| = 2472 (794 / 3266), |E| = 1789816, w = 435, p = 0.33569, d_min = 3, d_avg = 1148.78, d_max = 2000, k_max = 1066
[pmc: bounds updated - thread 11] time = 106.45 sec, |V| = 2445 (821 / 3266), |E| = 1789816, w = 435, p = 0.33569, d_min = 3, d_avg = 1148.78, d_max = 2000, k_max = 1066
[pmc: thread 2]
[pmc: bounds updated - thread 2] time = 122.339 sec, |V| = 2397 (869 / 3266), |E| = 1789816, w = 435, p = 0.33569, d_min = 3, d_avg = 1148.78, d_max = 2000, k_max = 1066
[pmc: bounds updated - thread 8] time = 158.845 sec, |V| = 2405 (861 / 3266), |E| = 1789816, w = 435, p = 0.33569, d_min = 3, d_avg = 1148.78, d_max = 2000, k_max = 1066
[pmc: bounds updated - thread 1] time = 387.939 sec, |V| = 2450 (816 / 3266), |E| = 1789816, w = 437, p = 0.33569, d_min = 3, d_avg = 1148.78, d_max = 2000, k_max = 1066
[pmc: bounds updated - thread 10] time = 428.297 sec, |V| = 2413 (853 / 3266), |E| = 1789816, w = 437, p = 0.33569, d_min = 3, d_avg = 1148.78, d_max = 2000, k_max = 1066
[pmc: bounds updated - thread 7] time = 466.339 sec, |V| = 2449 (817 / 3266), |E| = 1789816, w = 442, p = 0.33569, d_min = 3, d_avg = 1148.78, d_max = 2000, k_max = 1066
[pmc: bounds updated - thread 10] time = 486.135 sec, |V| = 2374 (892 / 3266), |E| = 1789816, w = 446, p = 0.33569, d_min = 3, d_avg = 1148.78, d_max = 2000, k_max = 1066
[pmc: bounds updated - thread 5] time = 488.205 sec, |V| = 2400 (866 / 3266), |E| = 1789816, w = 446, p = 0.33569, d_min = 3, d_avg = 1148.78, d_max = 2000, k_max = 1066
[pmc: bounds updated - thread 6] time = 495.076 sec, |V| = 2398 (868 / 3266), |E| = 1789816, w = 446, p = 0.33569, d_min = 3, d_avg = 1148.78, d_max = 2000, k_max = 1066
[pmc: bounds updated - thread 6] time = 514.081 sec, |V| = 2356 (910 / 3266), |E| = 1789816, w = 446, p = 0.33569, d_min = 3, d_avg = 1148.78, d_max = 2000, k_max = 1066
[pmc: bounds updated - thread 3] time = 627.889 sec, |V| = 2421 (845 / 3266), |E| = 1789816, w = 449, p = 0.33569, d_min = 3, d_avg = 1148.78, d_max = 2000, k_max = 1066
[pmc: bounds updated - thread 9] time = 644.015 sec, |V| = 2444 (822 / 3266), |E| = 1789816, w = 449, p = 0.33569, d_min = 3, d_avg = 1148.78, d_max = 2000, k_max = 1066
[pmc: thread 2]
[pmc: bounds updated - thread 2] time = 675.159 sec, |V| = 2389 (877 / 3266), |E| = 1789816, w = 449, p = 0.33569, d_min = 3, d_avg = 1148.78, d_max = 2000, k_max = 1066
[pmc: thread 2]
[pmc: bounds updated - thread 2] time = 679.467 sec, |V| = 2350 (916 / 3266), |E| = 1789816, w = 449, p = 0.33569, d_min = 3, d_avg = 1148.78, d_max = 2000, k_max = 1066
[pmc: bounds updated - thread 9] time = 799.512 sec, |V| = 2351 (915 / 3266), |E| = 1789816, w = 449, p = 0.33569, d_min = 3, d_avg = 1148.78, d_max = 2000, k_max = 1066
[pmc: bounds updated - thread 11] time = 801.483 sec, |V| = 2392 (874 / 3266), |E| = 1789816, w = 449, p = 0.33569, d_min = 3, d_avg = 1148.78, d_max = 2000, k_max = 1066
[pmc: thread 2]
[pmc: bounds updated - thread 2] time = 814.806 sec, |V| = 2347 (919 / 3266), |E| = 1789816, w = 449, p = 0.33569, d_min = 3, d_avg = 1148.78, d_max = 2000, k_max = 1066
[pmc: bounds updated - thread 9] time = 870.423 sec, |V| = 2346 (920 / 3266), |E| = 1789816, w = 449, p = 0.33569, d_min = 3, d_avg = 1148.78, d_max = 2000, k_max = 1066
[pmc: bounds updated - thread 12] time = 1064.85 sec, |V| = 2393 (873 / 3266), |E| = 1789816, w = 449, p = 0.33569, d_min = 3, d_avg = 1148.78, d_max = 2000, k_max = 1066
[pmc: bounds updated - thread 1] time = 4839.77 sec, |V| = 2385 (881 / 3266), |E| = 1789816, w = 450, p = 0.33569, d_min = 3, d_avg = 1148.78, d_max = 2000, k_max = 1066
[pmc: bounds updated - thread 6] time = 4994.77 sec, |V| = 2355 (911 / 3266), |E| = 1789816, w = 450, p = 0.33569, d_min = 3, d_avg = 1148.78, d_max = 2000, k_max = 1066