Amazon redshift 亚马逊红移吸尘器的单独队列

我正在考虑在WLM工作负载管理中为真空查询设置一个单独的队列，并发性设置为1。 我选择并发1是因为在任何给定时刻只有一个真空查询可以运行。我正在努力思考在这个实施过程中是否会出现任何问题

当我运行下面的查询来检查一个真空查询占用了多少插槽时，很明显，在任何给定的时间点，任何多级真空查询只占用了1个插槽

选择wlm.query、wlm.slot\u count、trimq.text、queue\u start\u time、queue\u end\u time、total\u queue\u time 从stl_wlm_查询wlm，stl_查询文本q 其中wlm.query=q.query 还有像“%Vacuum my_awesome_table%”这样的文本 按队列顺序\u开始\u时间描述

  query  | slot_count |                                     btrim                               |      queue_start_time      |       queue_end_time
---------+------------+-------------------------------------------------------------------------+----------------------------+-----------------------------
 1013242 |          1 | Vacuum my_awesome_table integrity check after vacuum execution          | 2018-04-27 16:46:47.90601  | 2018-04-27 16:46:47.90601
 1013237 |          1 | Vacuum my_awesome_table merge (increment: 2 remaining rows: 77234725)   | 2018-04-27 16:46:40.785284 | 2018-04-27 16:46:40.785284
 1013235 |          1 | Vacuum my_awesome_table merge (increment: 1)                            | 2018-04-27 16:46:29.789227 | 2018-04-27 16:46:29.789227
 1013232 |          1 | Vacuum my_awesome_table sort (partition: 35 remaining rows: 331972)     | 2018-04-27 16:46:16.978124 | 2018-04-27 16:46:16.978124
 1013231 |          1 | Vacuum my_awesome_table sort (partition: 34 remaining rows: 1458914)    | 2018-04-27 16:46:15.059653 | 2018-04-27 16:46:15.059653
 1013229 |          1 | Vacuum my_awesome_table sort (partition: 33 remaining rows: 2586321)    | 2018-04-27 16:46:13.641356 | 2018-04-27 16:46:13.641356
 1013228 |          1 | Vacuum my_awesome_table sort (partition: 32 remaining rows: 3713038)    | 2018-04-27 16:46:12.233741 | 2018-04-27 16:46:12.233741
 1013227 |          1 | Vacuum my_awesome_table sort (partition: 31 remaining rows: 4839275)    | 2018-04-27 16:46:10.838661 | 2018-04-27 16:46:10.838661
 1013226 |          1 | Vacuum my_awesome_table sort (partition: 30 remaining rows: 5965341)    | 2018-04-27 16:46:09.421457 | 2018-04-27 16:46:09.421457
 1013225 |          1 | Vacuum my_awesome_table sort (partition: 29 remaining rows: 7090572)    | 2018-04-27 16:46:07.93862  | 2018-04-27 16:46:07.93862
 1013224 |          1 | Vacuum my_awesome_table sort (partition: 28 remaining rows: 8215908)    | 2018-04-27 16:46:06.441227 | 2018-04-27 16:46:06.441227
 1013223 |          1 | Vacuum my_awesome_table sort (partition: 27 remaining rows: 9341191)    | 2018-04-27 16:46:05.009684 | 2018-04-27 16:46:05.009684
 1013222 |          1 | Vacuum my_awesome_table sort (partition: 26 remaining rows: 10467621)   | 2018-04-27 16:46:03.54458  | 2018-04-27 16:46:03.54458
 1013221 |          1 | Vacuum my_awesome_table sort (partition: 25 remaining rows: 11594203)   | 2018-04-27 16:46:01.998305 | 2018-04-27 16:46:01.998305
 1013218 |          1 | Vacuum my_awesome_table sort (partition: 24 remaining rows: 12720513)   | 2018-04-27 16:46:00.528971 | 2018-04-27 16:46:00.528971
 1013217 |          1 | Vacuum my_awesome_table sort (partition: 23 remaining rows: 13844984)   | 2018-04-27 16:45:59.071698 | 2018-04-27 16:45:59.071698
 1013216 |          1 | Vacuum my_awesome_table sort (partition: 22 remaining rows: 14970941)   | 2018-04-27 16:45:57.596597 | 2018-04-27 16:45:57.596597
 1013215 |          1 | Vacuum my_awesome_table sort (partition: 21 remaining rows: 16097323)   | 2018-04-27 16:45:56.253103 | 2018-04-27 16:45:56.253103
 1013214 |          1 | Vacuum my_awesome_table sort (partition: 20 remaining rows: 17223270)   | 2018-04-27 16:45:54.634498 | 2018-04-27 16:45:54.634498
 1013213 |          1 | Vacuum my_awesome_table sort (partition: 19 remaining rows: 18351994)   | 2018-04-27 16:45:53.265236 | 2018-04-27 16:45:53.265236
 1013212 |          1 | Vacuum my_awesome_table sort (partition: 18 remaining rows: 19477834)   | 2018-04-27 16:45:51.741294 | 2018-04-27 16:45:51.741294
 1013211 |          1 | Vacuum my_awesome_table sort (partition: 17 remaining rows: 20605101)   | 2018-04-27 16:45:50.338666 | 2018-04-27 16:45:50.338666
 1013210 |          1 | Vacuum my_awesome_table sort (partition: 16 remaining rows: 21730370)   | 2018-04-27 16:45:48.698214 | 2018-04-27 16:45:48.698214
 1013209 |          1 | Vacuum my_awesome_table sort (partition: 15 remaining rows: 22856152)   | 2018-04-27 16:45:46.27666  | 2018-04-27 16:45:46.27666
 1013208 |          1 | Vacuum my_awesome_table sort (partition: 14 remaining rows: 23981990)   | 2018-04-27 16:45:43.603719 | 2018-04-27 16:45:43.603719
 1013206 |          1 | Vacuum my_awesome_table sort (partition: 13 remaining rows: 25107349)   | 2018-04-27 16:45:40.848632 | 2018-04-27 16:45:40.848632
 1013205 |          1 | Vacuum my_awesome_table sort (partition: 12 remaining rows: 26233207)   | 2018-04-27 16:45:38.097134 | 2018-04-27 16:45:38.097134
 1013204 |          1 | Vacuum my_awesome_table sort (partition: 11 remaining rows: 27359056)   | 2018-04-27 16:45:35.316781 | 2018-04-27 16:45:35.316781
 1013203 |          1 | Vacuum my_awesome_table sort (partition: 10 remaining rows: 28486363)   | 2018-04-27 16:45:33.815825 | 2018-04-27 16:45:33.815825
 1013202 |          1 | Vacuum my_awesome_table sort (partition: 9 remaining rows: 29612051)    | 2018-04-27 16:45:32.262505 | 2018-04-27 16:45:32.262505
 1013201 |          1 | Vacuum my_awesome_table sort (partition: 8 remaining rows: 30738238)    | 2018-04-27 16:45:30.867315 | 2018-04-27 16:45:30.867315
 1013200 |          1 | Vacuum my_awesome_table sort (partition: 7 remaining rows: 31864515)    | 2018-04-27 16:45:29.476297 | 2018-04-27 16:45:29.476297
 1013197 |          1 | Vacuum my_awesome_table sort (partition: 6 remaining rows: 32989591)    | 2018-04-27 16:45:28.023365 | 2018-04-27 16:45:28.023365
 1013196 |          1 | Vacuum my_awesome_table sort (partition: 5 remaining rows: 34115286)    | 2018-04-27 16:45:26.607642 | 2018-04-27 16:45:26.607642
 1013195 |          1 | Vacuum my_awesome_table sort (partition: 4 remaining rows: 35241021)    | 2018-04-27 16:45:25.179251 | 2018-04-27 16:45:25.179251
 1013194 |          1 | Vacuum my_awesome_table sort (partition: 3 remaining rows: 36367702)    | 2018-04-27 16:45:23.167024 | 2018-04-27 16:45:23.167024
 1013193 |          1 | Vacuum my_awesome_table sort (partition: 2 remaining rows: 37493086)    | 2018-04-27 16:45:21.550219 | 2018-04-27 16:45:21.550219
 1013192 |          1 | Vacuum my_awesome_table sort (partition: 1)                             | 2018-04-27 16:45:13.472849 | 2018-04-27 16:45:13.472849
 1013188 |          1 | Vacuum my_awesome_table integrity check before vacuum execution         | 2018-04-27 16:45:13.083657 | 2018-04-27 16:45:13.083657
 1008690 |          1 | Vacuum my_awesome_table integrity check after vacuum execution          | 2018-04-27 09:00:23.795686 | 2018-04-27 09:00:23.795686
 1008686 |          1 | Vacuum my_awesome_table merge (increment: 2 remaining rows: 115824559)  | 2018-04-27 09:00:15.527474 | 2018-04-27 09:00:15.527474
 1008680 |          1 | Vacuum my_awesome_table merge (increment: 1)                            | 2018-04-27 09:00:00.946362 | 2018-04-27 09:00:00.946362

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使用多个队列的想法是阻止一组查询干扰另一组查询。将真空放在单独的队列中意味着其他查询不会受到长期真空的影响

对于真空，并发度为1是可以的

更重要的是你给它的内存量——越多越好，但你也不想在真空没有运行时浪费内存

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因此，如果您只在一天中的一部分时间运行真空，那么剩余时间的队列将被浪费。这可能不适合您的情况。

谢谢您的见解，John。我的想法是一样的，你的回答证实了我的想法。关于如何从其他较短查询路径中剔除长时间运行的真空作业，您有什么想法吗？是否可以安排WLM安装脚本？像设置真空队列的最高优先级一样，运行真空，然后设置回正常状态mode@PratikKhadloya真空完全在你自己的控制之下-你需要自己发出命令。因此，使用SET query_group TO，然后发出VACUUM命令。更好的选择是使用正常队列，但在夜间集群不使用时运行真空。您甚至可以使用设置wlm\u query\u slot\u count来运行真空吸尘器，以便在真空吸尘器运行时为其分配多个插槽。这给了它更多的内存，所以它应该运行得更快。谢谢你的信息。我们一天运行3次真空吸尘器，因为以前一天运行一次是不够的，因为我们每小时更新很多表。您的表是否按时间排序？如果是这样，按时间顺序加载它们意味着您不需要真空吸尘器。类似地，按排序键顺序加载可以避免抽真空。细节：