关于 region split 机制的疑问

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12

刚才去测了一下，参数设置和问题中一致，发现刚刚分裂时确实左右 region 一模一样大，虽然我一直是自增ID插入的，有时候它似乎不一定会在整个区间的尾部拆分新 region，反而可能会调整区间头部的的 region，即使当时并未向其中插入新数据。。（从 340000 到 440000 的 region 变化）

有点奇怪

无数据时

REGION_ID START_KEY END_KEY LEADER_ID LEADER_STORE_ID PEERS SCATTERING WRITTEN_BYTES READ_BYTES APPROXIMATE_SIZE(MB) APPROXIMATE_KEYS SCHEDULING_CONSTRAINTS SCHEDULING_STATE
1152529 t_25197_ 1152531 7 1152530, 1152531, 1152532 0 248 138042 29 41397

插入至 160000 条数据

  • 刚 split 后
REGION_ID START_KEY END_KEY LEADER_ID LEADER_STORE_ID PEERS SCATTERING WRITTEN_BYTES READ_BYTES APPROXIMATE_SIZE(MB) APPROXIMATE_KEYS SCHEDULING_CONSTRAINTS SCHEDULING_STATE
1315381 t_25197_ t_25197_r_108643 1315383 7 1315382, 1315383, 1315384 0 39 0 75 321510
1152529 t_25197_r_108643 1152531 7 1152530, 1152531, 1152532 0 95544232 119890 75 321510
  • split 后一段时间
REGION_ID START_KEY END_KEY LEADER_ID LEADER_STORE_ID PEERS SCATTERING WRITTEN_BYTES READ_BYTES APPROXIMATE_SIZE(MB) APPROXIMATE_KEYS SCHEDULING_CONSTRAINTS SCHEDULING_STATE
1315381 t_25197_ t_25197_r_108643 1315383 7 1315382, 1315383, 1315384 0 0 97245772 95 537284
1152529 t_25197_r_108643 1152531 7 1152530, 1152531, 1152532 0 0 293310 131 103120

插入至 340000 条数据

  • 刚 split 后
REGION_ID START_KEY END_KEY LEADER_ID LEADER_STORE_ID PEERS SCATTERING WRITTEN_BYTES READ_BYTES APPROXIMATE_SIZE(MB) APPROXIMATE_KEYS SCHEDULING_CONSTRAINTS SCHEDULING_STATE
1315381 t_25197_ t_25197_r_108643 1315383 7 1315382, 1315383, 1315384 0 47125038 117705772 123 817284
1315385 t_25197_r_108643 t_25197_r_270175 1315387 7 1315386, 1315387, 1315388 0 0 0 81 232868
1152529 t_25197_r_270175 1152531 7 1152530, 1152531, 1152532 0 64541976 119092468 81 232868
  • split 后一段时间
REGION_ID START_KEY END_KEY LEADER_ID LEADER_STORE_ID PEERS SCATTERING WRITTEN_BYTES READ_BYTES APPROXIMATE_SIZE(MB) APPROXIMATE_KEYS SCHEDULING_CONSTRAINTS SCHEDULING_STATE
1315381 t_25197_ t_25197_r_108643 1315383 7 1315382, 1315383, 1315384 0 31416720 63240000 131 897284
1315385 t_25197_r_108643 t_25197_r_270175 1315387 7 1315386, 1315387, 1315388 0 0 0 81 232868
1152529 t_25197_r_270175 1152531 7 1152530, 1152531, 1152532 0 266 67055 119 106304

插入至 440000 条数据

  • 刚 split 后
REGION_ID START_KEY END_KEY LEADER_ID LEADER_STORE_ID PEERS SCATTERING WRITTEN_BYTES READ_BYTES APPROXIMATE_SIZE(MB) APPROXIMATE_KEYS SCHEDULING_CONSTRAINTS SCHEDULING_STATE
1315389 t_25197_ t_25197_r_16084 1315391 7 1315390, 1315391, 1315392 0 39 0 75 548642
1315381 t_25197_r_16084 t_25197_r_108643 1315383 7 1315382, 1315383, 1315384 0 78541260 40920000 75 548642
1315385 t_25197_r_108643 t_25197_r_270175 1315387 7 1315386, 1315387, 1315388 0 39 0 110 75297
1152529 t_25197_r_270175 1152531 7 1152530, 1152531, 1152532 0 0 293310 119 106304
  • split 后一段时间
REGION_ID START_KEY END_KEY LEADER_ID LEADER_STORE_ID PEERS SCATTERING WRITTEN_BYTES READ_BYTES APPROXIMATE_SIZE(MB) APPROXIMATE_KEYS SCHEDULING_CONSTRAINTS SCHEDULING_STATE
1315389 t_25197_ t_25197_r_16084 1315391 7 1315390, 1315391, 1315392 0 0 0 107 902733
1315381 t_25197_r_16084 t_25197_r_108643 1315383 7 1315382, 1315383, 1315384 0 278 0 52 81920
1315385 t_25197_r_108643 t_25197_r_270175 1315387 7 1315386, 1315387, 1315388 0 39 0 110 75297
1152529 t_25197_r_270175 1152531 7 1152530, 1152531, 1152532 0 0 293310 138 228509

插入至 540000 条数据

  • 刚 split 后
REGION_ID START_KEY END_KEY LEADER_ID LEADER_STORE_ID PEERS SCATTERING WRITTEN_BYTES READ_BYTES APPROXIMATE_SIZE(MB) APPROXIMATE_KEYS SCHEDULING_CONSTRAINTS SCHEDULING_STATE
1315389 t_25197_ t_25197_r_16084 1315391 7 1315390, 1315391, 1315392 0 78540552 60210511 126 1214773
1315381 t_25197_r_16084 t_25197_r_108643 1315383 7 1315382, 1315383, 1315384 0 0 57495261 52 81920
1315385 t_25197_r_108643 t_25197_r_270175 1315387 7 1315386, 1315387, 1315388 0 39 0 110 75297
1315393 t_25197_r_270175 t_25197_r_431708 1315395 7 1315394, 1315395, 1315396 0 39 0 92 271336
1152529 t_25197_r_431708 1152531 7 1152530, 1152531, 1152532 0 80676142 86015 92 271336
  • split 后一段时间
REGION_ID START_KEY END_KEY LEADER_ID LEADER_STORE_ID PEERS SCATTERING WRITTEN_BYTES READ_BYTES APPROXIMATE_SIZE(MB) APPROXIMATE_KEYS SCHEDULING_CONSTRAINTS SCHEDULING_STATE
1315389 t_25197_ t_25197_r_16084 1315391 7 1315390, 1315391, 1315392 0 0 50220000 126 1214773
1315381 t_25197_r_16084 t_25197_r_108643 1315383 7 1315382, 1315383, 1315384 0 0 0 52 81920
1315385 t_25197_r_108643 t_25197_r_270175 1315387 7 1315386, 1315387, 1315388 0 0 100339986 110 75297
1315393 t_25197_r_270175 t_25197_r_431708 1315395 7 1315394, 1315395, 1315396 0 0 100340050 95 157031
1152529 t_25197_r_431708 1152531 7 1152530, 1152531, 1152532 0 0 289060 109 154677

插入至 660000 条数据

  • 刚 split 后
REGION_ID START_KEY END_KEY LEADER_ID LEADER_STORE_ID PEERS SCATTERING WRITTEN_BYTES READ_BYTES APPROXIMATE_SIZE(MB) APPROXIMATE_KEYS SCHEDULING_CONSTRAINTS SCHEDULING_STATE
1315389 t_25197_ t_25197_r_16084 1315391 7 1315390, 1315391, 1315392 0 94250670 107456465 141 1294794
1315381 t_25197_r_16084 t_25197_r_108643 1315383 7 1315382, 1315383, 1315384 0 0 0 52 81920
1315385 t_25197_r_108643 t_25197_r_270175 1315387 7 1315386, 1315387, 1315388 0 0 0 110 75297
1315393 t_25197_r_270175 t_25197_r_431708 1315395 7 1315394, 1315395, 1315396 0 0 0 95 157031
1315397 t_25197_r_431708 t_25197_r_593240 1315399 7 1315398, 1315399, 1315400 0 39 0 80 229803
1152529 t_25197_r_593240 1152531 7 1152530, 1152531, 1152532 0 96808754 71305 80 229803
  • split 后一段时间
REGION_ID START_KEY END_KEY LEADER_ID LEADER_STORE_ID PEERS SCATTERING WRITTEN_BYTES READ_BYTES APPROXIMATE_SIZE(MB) APPROXIMATE_KEYS SCHEDULING_CONSTRAINTS SCHEDULING_STATE
1315389 t_25197_ t_25197_r_16084 1315391 7 1315390, 1315391, 1315392 0 94250670 107456465 141 1294794
1315381 t_25197_r_16084 t_25197_r_108643 1315383 7 1315382, 1315383, 1315384 0 0 0 52 81920
1315385 t_25197_r_108643 t_25197_r_270175 1315387 7 1315386, 1315387, 1315388 0 0 0 110 75297
1315393 t_25197_r_270175 t_25197_r_431708 1315395 7 1315394, 1315395, 1315396 0 0 0 95 157031
1315397 t_25197_r_431708 t_25197_r_593240 1315399 7 1315398, 1315399, 1315400 0 39 0 80 229803
1152529 t_25197_r_593240 1152531 7 1152530, 1152531, 1152532 0 266 222005 77 121525