MySQL HeatWave Quickstart AutoPilot简介
2024-04-20 22:23:01
本文是MySQL HeatWave Quickstart (快速入门)的续篇。
今天看了下MySQL HeatWave用户手册，已由60多页变为96页，增加了Autopilot，对象存储持久化层等内容。
基本概念：
- HeatWave是内存列式的，分布式的，无共享的
- HeatWave Cluster包括1个InnoDB和多个HeatWave节点（至少2个，最多64个）。
- HeatWave只在Oracle的公有云上提供。
先看下最新架构：
图中的OCI Object Storage是最新的功能，目的是：
HeatWave Storage Layer automatically persists the data to OCI Object Storage for fast recovery in case of a HeatWave node or cluster failure.
The time required to reload data is constant regardless of data size or HeatWave cluster size.
文中谈到了Push-Based Vectorized Query Processing的概念，相对于tuple-based，描述为：
HeatWave processes queries by pushing vector blocks (slices of columnar data) through the query execution plan from one operator to another. A push-based execution model avoids deep call stacks and saves valuable resources compared to tuple-based processing models.
还不太懂，后续再看。
一张表被分布到所有HeatWave节点，因此其需要主键。
Shape目前可以选择2种：
- MySQL.HeatWave.VM.Standard.E3 （16 OCPU，512GB RAM）
- MySQL.HeatWave.BM.Standard.E3（128 OCPU，2TB RAM）
AutoPilot可参见Oracle Announces MySQL Autopilot for MySQL HeatWave Service。
以及MySQL Autopilot - Machine Learning Automation for MySQL HeatWave。
AutoPilot是基于机器学习的自动化服务。
来看一下AutoPilot的4大功能：
System Setup
Auto provisioning
帮助见这里。
可以自动估算HeatWave Cluster的节点数量。见菜单“Estimate Node Count”。
此步骤执行时，Schema里必须有数据。输出中表示估算节点数是1，但最小应为2。
Data Load
Auto Parallel Load，Auto Encoding，Auto Data Placement 3项子功能。
Auto Parallel Load
帮助见这里。可以指定表，为简化，下例指定整个Schema。
先来看Auto Parallel Load，其实就是执行在节点估算时给出的命令，这比之前方便太多了！：
MySQL 10.0.1.28:3306 ssl tpch SQL > CALL sys.heatwave_load(JSON_ARRAY("tpch"), NULL);
+------------------------------------------+
| INITIALIZING HEATWAVE AUTO LOAD |
+------------------------------------------+
| Version: 1.15 |
| |
| Load Mode: normal |
| Load Policy: disable_unsupported_columns |
| Output Mode: normal |
| |
+------------------------------------------+
6 rows in set (0.0080 sec)+------------------------------------------------------------------------+
| OFFLOAD ANALYSIS |
+------------------------------------------------------------------------+
| Verifying input schemas: 1 |
| User excluded items: 0 |
| |
| SCHEMA OFFLOADABLE OFFLOADABLE SUMMARY OF |
| NAME TABLES COLUMNS ISSUES |
| ------ ----------- ----------- ---------- |
| `tpch` 8 61 |
| |
| Total offloadable schemas: 1 |
| |
+------------------------------------------------------------------------+
10 rows in set (0.0080 sec)+-----------------------------------------------------------------------------------------------------------------------------+
| CAPACITY ESTIMATION |
+-----------------------------------------------------------------------------------------------------------------------------+
| Default load pool for tables: TRANSACTIONAL |
| Default encoding for string columns: VARLEN (unless specified in the schema) |
| Estimating memory footprint for 1 schema(s) |
| |
| TOTAL ESTIMATED ESTIMATED TOTAL DICTIONARY VARLEN ESTIMATED |
| SCHEMA OFFLOADABLE HEATWAVE NODE MYSQL NODE STRING ENCODED ENCODED LOAD |
| NAME TABLES FOOTPRINT FOOTPRINT COLUMNS COLUMNS COLUMNS TIME |
| ------ ----------- --------- --------- ------- ---------- ------- --------- |
| `tpch` 8 2.22 GiB 32.00 MiB 29 0 29 10.00 s |
| |
| Sufficient MySQL host memory available to load all tables. |
| Sufficient HeatWave cluster memory available to load all tables. |
| |
+-----------------------------------------------------------------------------------------------------------------------------+
13 rows in set (0.0080 sec)+---------------------------------------------------------------------------------------------------------------------------------------+
| EXECUTING LOAD |
+---------------------------------------------------------------------------------------------------------------------------------------+
| HeatWave Load script generated |
| Retrieve load script containing 24 generated DDL command(s) using the query below: |
| SELECT log->>"$.sql" AS "Load Script" FROM sys.heatwave_load_report WHERE type = "sql" ORDER BY id; |
| |
| Adjusting load parallelism dynamically per table |
| Using current parallelism of 32 thread(s) as maximum |
| |
| Using SQL_MODE: ONLY_FULL_GROUP_BY,STRICT_TRANS_TABLES,NO_ZERO_IN_DATE,NO_ZERO_DATE,ERROR_FOR_DIVISION_BY_ZERO,NO_ENGINE_SUBSTITUTION |
| |
| Proceeding to load 8 tables into HeatWave |
| |
| Applying changes will take approximately 9.74 s |
| |
+---------------------------------------------------------------------------------------------------------------------------------------+
13 rows in set (0.0080 sec)+----------------------------------------+
| LOADING TABLE |
+----------------------------------------+
| TABLE (1 of 8): `tpch`.`customer` |
| Commands executed successfully: 3 of 3 |
| Warnings encountered: 0 |
| Table loaded successfully! |
| Total columns loaded: 8 |
| Table loaded using 3 thread(s) |
| |
+----------------------------------------+
7 rows in set (0.0080 sec)+----------------------------------------+
| LOADING TABLE |
+----------------------------------------+
| TABLE (2 of 8): `tpch`.`lineitem` |
| Commands executed successfully: 3 of 3 |
| Warnings encountered: 0 |
| Table loaded successfully! |
| Total columns loaded: 16 |
| Table loaded using 32 thread(s) |
| |
+----------------------------------------+
7 rows in set (0.0080 sec)+----------------------------------------+
| LOADING TABLE |
+----------------------------------------+
| TABLE (3 of 8): `tpch`.`nation` |
| Commands executed successfully: 3 of 3 |
| Warnings encountered: 0 |
| Table loaded successfully! |
| Total columns loaded: 4 |
| Table loaded using 1 thread(s) |
| |
+----------------------------------------+
7 rows in set (0.0080 sec)+----------------------------------------+
| LOADING TABLE |
+----------------------------------------+
| TABLE (4 of 8): `tpch`.`orders` |
| Commands executed successfully: 3 of 3 |
| Warnings encountered: 0 |
| Table loaded successfully! |
| Total columns loaded: 9 |
| Table loaded using 16 thread(s) |
| |
+----------------------------------------+
7 rows in set (0.0080 sec)+----------------------------------------+
| LOADING TABLE |
+----------------------------------------+
| TABLE (5 of 8): `tpch`.`part` |
| Commands executed successfully: 3 of 3 |
| Warnings encountered: 0 |
| Table loaded successfully! |
| Total columns loaded: 9 |
| Table loaded using 4 thread(s) |
| |
+----------------------------------------+
7 rows in set (0.0080 sec)+----------------------------------------+
| LOADING TABLE |
+----------------------------------------+
| TABLE (6 of 8): `tpch`.`partsupp` |
| Commands executed successfully: 3 of 3 |
| Warnings encountered: 0 |
| Table loaded successfully! |
| Total columns loaded: 5 |
| Table loaded using 15 thread(s) |
| |
+----------------------------------------+
7 rows in set (0.0080 sec)+----------------------------------------+
| LOADING TABLE |
+----------------------------------------+
| TABLE (7 of 8): `tpch`.`region` |
| Commands executed successfully: 3 of 3 |
| Warnings encountered: 0 |
| Table loaded successfully! |
| Total columns loaded: 3 |
| Table loaded using 1 thread(s) |
| |
+----------------------------------------+
7 rows in set (0.0080 sec)+----------------------------------------+
| LOADING TABLE |
+----------------------------------------+
| TABLE (8 of 8): `tpch`.`supplier` |
| Commands executed successfully: 3 of 3 |
| Warnings encountered: 0 |
| Table loaded successfully! |
| Total columns loaded: 7 |
| Table loaded using 1 thread(s) |
| |
+----------------------------------------+
7 rows in set (0.0080 sec)+-------------------------------------------------------------------------------+
| LOAD SUMMARY |
+-------------------------------------------------------------------------------+
| |
| SCHEMA TABLES TABLES COLUMNS LOAD |
| NAME LOADED FAILED LOADED DURATION |
| ------ ------ ------ ------- -------- |
| `tpch` 8 0 61 2.55 s |
| |
+-------------------------------------------------------------------------------+
6 rows in set (0.0080 sec)Query OK, 0 rows affected (0.0080 sec)
相关查看命令：
MySQL 10.0.1.28:3306 ssl tpch SQL > SELECT log FROM sys.heatwave_load_report WHERE type="error";
Empty set (0.0007 sec)MySQL 10.0.1.28:3306 ssl tpch SQL > SELECT log FROM sys.heatwave_load_report WHERE type="warn";
Empty set (0.0006 sec)MySQL 10.0.1.28:3306 ssl tpch SQL > SELECT log->>"$.sql" AS "Load Script" FROM sys.heatwave_load_report-> WHERE type = "sql" ORDER BY id;
+-------------------------------------------------------+
| Load Script |
+-------------------------------------------------------+
| SET SESSION innodb_parallel_read_threads = 3; |
| ALTER TABLE `tpch`.`customer` SECONDARY_ENGINE=RAPID; |
| ALTER TABLE `tpch`.`customer` SECONDARY_LOAD; |
| SET SESSION innodb_parallel_read_threads = 32; |
| ALTER TABLE `tpch`.`lineitem` SECONDARY_ENGINE=RAPID; |
| ALTER TABLE `tpch`.`lineitem` SECONDARY_LOAD; |
| SET SESSION innodb_parallel_read_threads = 1; |
| ALTER TABLE `tpch`.`nation` SECONDARY_ENGINE=RAPID; |
| ALTER TABLE `tpch`.`nation` SECONDARY_LOAD; |
| SET SESSION innodb_parallel_read_threads = 16; |
| ALTER TABLE `tpch`.`orders` SECONDARY_ENGINE=RAPID; |
| ALTER TABLE `tpch`.`orders` SECONDARY_LOAD; |
| SET SESSION innodb_parallel_read_threads = 4; |
| ALTER TABLE `tpch`.`part` SECONDARY_ENGINE=RAPID; |
| ALTER TABLE `tpch`.`part` SECONDARY_LOAD; |
| SET SESSION innodb_parallel_read_threads = 15; |
| ALTER TABLE `tpch`.`partsupp` SECONDARY_ENGINE=RAPID; |
| ALTER TABLE `tpch`.`partsupp` SECONDARY_LOAD; |
| SET SESSION innodb_parallel_read_threads = 1; |
| ALTER TABLE `tpch`.`region` SECONDARY_ENGINE=RAPID; |
| ALTER TABLE `tpch`.`region` SECONDARY_LOAD; |
| SET SESSION innodb_parallel_read_threads = 1; |
| ALTER TABLE `tpch`.`supplier` SECONDARY_ENGINE=RAPID; |
| ALTER TABLE `tpch`.`supplier` SECONDARY_LOAD; |
+-------------------------------------------------------+
24 rows in set (0.0007 sec)
Auto Encoding
帮助见这里。
实际就是建议器，决定是VARLEN还是DICTIONARY编码.
以下输出中，建议部分列的编码从VARLEN改为DICTIONARY，以提升性能。而且还给出命令，以生成修改脚本。
MySQL 10.0.1.28:3306 ssl tpch SQL > CALL sys.heatwave_advisor(JSON_OBJECT("auto_enc",JSON_OBJECT("mode","recommend")));
+-------------------------------+
| INITIALIZING HEATWAVE ADVISOR |
+-------------------------------+
| Version: 1.15 |
| |
| Output Mode: normal |
| Excluded Queries: 0 |
| Target Schemas: All |
| |
+-------------------------------+
6 rows in set (0.0098 sec)+---------------------------------------------------------+
| ANALYZING LOADED DATA |
+---------------------------------------------------------+
| Total 8 tables loaded in HeatWave for 1 schemas |
| Tables excluded by user: 0 (within target schemas) |
| |
| SCHEMA TABLES COLUMNS |
| NAME LOADED LOADED |
| ------ ------ ------ |
| `tpch` 8 61 |
| |
+---------------------------------------------------------+
8 rows in set (0.0098 sec)+--------------------------------------------------------------------------------------------+
| ENCODING SUGGESTIONS |
+--------------------------------------------------------------------------------------------+
| Total Auto Encoding suggestions produced for 25 columns |
| Queries executed: 1 |
| Total query execution time: 0 ps |
| Most recent query executed on: Thursday 1st January 1970 00:00:00 |
| Oldest query executed on: Thursday 1st January 1970 00:00:00 |
| |
| CURRENT SUGGESTED |
| COLUMN COLUMN COLUMN |
| NAME ENCODING ENCODING |
| ------ -------- --------- |
| `tpch`.`customer`.`C_ADDRESS` VARLEN DICTIONARY |
| `tpch`.`customer`.`C_COMMENT` VARLEN DICTIONARY |
| `tpch`.`customer`.`C_MKTSEGMENT` VARLEN DICTIONARY |
| `tpch`.`customer`.`C_NAME` VARLEN DICTIONARY |
| `tpch`.`customer`.`C_PHONE` VARLEN DICTIONARY |
| `tpch`.`lineitem`.`L_COMMENT` VARLEN DICTIONARY |
| `tpch`.`lineitem`.`L_SHIPINSTRUCT` VARLEN DICTIONARY |
| `tpch`.`nation`.`N_COMMENT` VARLEN DICTIONARY |
| `tpch`.`nation`.`N_NAME` VARLEN DICTIONARY |
| `tpch`.`orders`.`O_CLERK` VARLEN DICTIONARY |
| `tpch`.`orders`.`O_COMMENT` VARLEN DICTIONARY |
| `tpch`.`orders`.`O_ORDERPRIORITY` VARLEN DICTIONARY |
| `tpch`.`part`.`P_BRAND` VARLEN DICTIONARY |
| `tpch`.`part`.`P_COMMENT` VARLEN DICTIONARY |
| `tpch`.`part`.`P_CONTAINER` VARLEN DICTIONARY |
| `tpch`.`part`.`P_MFGR` VARLEN DICTIONARY |
| `tpch`.`part`.`P_NAME` VARLEN DICTIONARY |
| `tpch`.`part`.`P_TYPE` VARLEN DICTIONARY |
| `tpch`.`partsupp`.`PS_COMMENT` VARLEN DICTIONARY |
| `tpch`.`region`.`R_COMMENT` VARLEN DICTIONARY |
| `tpch`.`region`.`R_NAME` VARLEN DICTIONARY |
| `tpch`.`supplier`.`S_ADDRESS` VARLEN DICTIONARY |
| `tpch`.`supplier`.`S_COMMENT` VARLEN DICTIONARY |
| `tpch`.`supplier`.`S_NAME` VARLEN DICTIONARY |
| `tpch`.`supplier`.`S_PHONE` VARLEN DICTIONARY |
| |
| Applying the suggested encodings might improve query performance and cluster memory usage. |
| Estimated HeatWave cluster memory savings: 348.50 MiB |
| |
+--------------------------------------------------------------------------------------------+
39 rows in set (0.0098 sec)+----------------------------------------------------------------------------------------------------------------+
| SCRIPT GENERATION |
+----------------------------------------------------------------------------------------------------------------+
| Script generated for applying suggestions for 8 loaded tables |
| |
| Applying changes will take approximately 11.00 s |
| |
| Retrieve script containing 65 generated DDL commands using the query below: |
| SELECT log->>"$.sql" AS "SQL Script" FROM sys.heatwave_advisor_report WHERE type = "sql" ORDER BY id; |
| |
| Caution: Executing the generated script will alter the column comment and secondary engine flags in the schema |
| |
+----------------------------------------------------------------------------------------------------------------+
9 rows in set (0.0098 sec)Query OK, 0 rows affected (0.0098 sec)
Auto Data Placement
帮助见这里。
给出data placement key的建议。
必须已经运行了一些查询，至少5个。
显示历史查询：
SELECT query_id, LEFT(query_text,160) FROM performance_schema.rpd_query_stats;
执行建议器：
MySQL 10.0.1.28:3306 ssl tpch SQL > CALL sys.heatwave_advisor(JSON_OBJECT("target_schema",JSON_ARRAY("tpch")));
+-------------------------------+
| INITIALIZING HEATWAVE ADVISOR |
+-------------------------------+
| Version: 1.15 |
| |
| Output Mode: normal |
| Excluded Queries: 0 |
| Target Schemas: 1 |
| |
+-------------------------------+
6 rows in set (0.0069 sec)+---------------------------------------------------------+
| ANALYZING LOADED DATA |
+---------------------------------------------------------+
| Total 8 tables loaded in HeatWave for 1 schemas |
| Tables excluded by user: 0 (within target schemas) |
| |
| SCHEMA TABLES COLUMNS |
| NAME LOADED LOADED |
| ------ ------ ------ |
| `tpch` 8 61 |
| |
+---------------------------------------------------------+
8 rows in set (0.0069 sec)+------------------------------------------------------------------------+
| AUTO DATA PLACEMENT |
+------------------------------------------------------------------------+
| Auto Data Placement Configuration: |
| |
| Minimum benefit threshold: 1% |
| |
| Producing Data Placement suggestions for current setup: |
| |
| Tables Loaded: 8 |
| Queries used: 6 |
| Total query execution time: 5.85 s |
| Most recent query executed on: Friday 10th September 2021 08:50:33 |
| Oldest query executed on: Friday 10th September 2021 08:47:25 |
| HeatWave cluster size: 2 nodes |
| |
+------------------------------------------------------------------------+
13 rows in set (0.0069 sec)+--------------------------------------------------------------------------------------+
| DATA PLACEMENT SUGGESTIONS |
+--------------------------------------------------------------------------------------+
| No Data Placement suggestion produced |
| Issue: No candidate Data Placement suggestion found where performance benefit > 1% |
+--------------------------------------------------------------------------------------+
2 rows in set (0.0069 sec)Query OK, 0 rows affected (0.0069 sec)
Query Execution
Auto Query Plan Improvement
详见这里。自动的特性，不赘述。
Auto Query Time Estimation
也称为Query Insight。详见这里。
前提必须有查询历史。
MySQL 10.0.1.28:3306 ssl tpch SQL > CALL sys.heatwave_advisor(JSON_OBJECT("query_insights", TRUE));
+-------------------------------+
| INITIALIZING HEATWAVE ADVISOR |
+-------------------------------+
| Version: 1.15 |
| |
| Output Mode: normal |
| Excluded Queries: 0 |
| Target Schemas: All |
| |
+-------------------------------+
6 rows in set (0.0074 sec)+---------------------------------------------------------+
| ANALYZING LOADED DATA |
+---------------------------------------------------------+
| Total 8 tables loaded in HeatWave for 1 schemas |
| Tables excluded by user: 0 (within target schemas) |
| |
| SCHEMA TABLES COLUMNS |
| NAME LOADED LOADED |
| ------ ------ ------ |
| `tpch` 8 61 |
| |
+---------------------------------------------------------+
8 rows in set (0.0074 sec)+--------------------------------------------------------------------------------------------------------------------+
| QUERY INSIGHTS |
+--------------------------------------------------------------------------------------------------------------------+
| Queries executed on Heatwave: 13 |
| Session IDs (as filter): None |
| |
| QUERY-ID SESSION-ID QUERY-STRING EXEC-RUNTIME (s) COMMENT |
| -------- ---------- ------------ ---------------- ------- |
| 1 21 SELECT SUM(l_extendedprice * l_discount) AS revenue ... 0.001 (est.) Explain. |
| 2 21 SELECT l_returnflag, l_linestatus, SUM(l_quantit... 0.226 |
| 3 21 SELECT l_orderkey, SUM(l_extendedprice * (1 - l_disc... 0.352 |
| 4 21 SELECT nation, o_year, SUM(amount) AS sum_profit FROM ... 0.233 |
| 5 21 select c_custkey, c_name, sum(l_extendedprice * (1 - l_disco... 4.923 |
| 6 21 select ps_partkey, sum(ps_supplycost * ps_availqty) as value... 0.039 |
| 7 21 select ps_partkey, sum(ps_supplycost * ps_availqty) as value... 0.079 |
| 8 21 SELECT l_orderkey, SUM(l_extendedprice * (1 - l_disc... 0.039 |
| 9 21 SELECT l_orderkey, SUM(l_extendedprice * (1 - l_disc... 0.050 |
| 10 21 SELECT l_orderkey, SUM(l_extendedprice * (1 - l_disc... 0.040 |
| 11 21 SELECT l_orderkey, SUM(l_extendedprice * (1 - l_disc... 0.047 |
| 12 21 SELECT l_orderkey, SUM(l_extendedprice * (1 - l_disc... 0.006 (est.) Explain. |
| 13 21 SELECT l_orderkey, SUM(l_extendedprice * (1 - l_disc... 0.006 (est.) Explain. |
| |
| TOTAL ESTIMATED: 3 EXEC-RUNTIME: 0.012 sec |
| TOTAL EXECUTED: 10 EXEC-RUNTIME: 6.029 sec |
| |
| |
| Retrieve detailed query statistics using the query below: |
| SELECT log FROM sys.heatwave_advisor_report WHERE stage = "QUERY_INSIGHTS" AND type = "info"; |
| |
+--------------------------------------------------------------------------------------------------------------------+
26 rows in set (0.0074 sec)Query OK, 0 rows affected (0.0074 sec)
Auto Change Propagation
指在InnoDB端修改的数据智能决定何时传播到HeatWave的存储层。
Auto Scheduling
HeatWave uses a workload-aware, priority-based, automated scheduling mechanism to schedule concurrently issued queries for execution. The scheduling mechanism prioritizes short-running queries but considers wait time in the queue so that costlier queries are eventually scheduled for execution. This scheduling approach reduces query execution wait times overall.
指当存在多个查询时，决定哪个先执行。
Failure Handling
Auto Error Recovery
Provisions new HeatWave nodes and reloads data from the HeatWave storage layer if one or more HeatWave nodes becomes unresponsive due to a software or hardware failure.
此时体现出对象存储持久化的好处了。
详见这里。
查看状态的SQL：
MySQL 10.0.1.28:3306 ssl tpch SQL > SHOW STATUS LIKE 'rapid_service_status';
+----------------------+--------+
| Variable_name | Value |
+----------------------+--------+
| rapid_service_status | ONLINE |
+----------------------+--------+
1 row in set (0.0015 sec)MySQL 10.0.1.28:3306 ssl tpch SQL > USE performance_schema;
Default schema set to `performance_schema`.
Fetching table and column names from `performance_schema` for auto-completion... Press ^C to stop.MySQL 10.0.1.28:3306 ssl performance_schema SQL > SELECT NAME, LOAD_STATUS FROM rpd_tables,rpd_table_id WHERE rpd_tables.ID = rpd_table_id.ID;+---------------+---------------------+
| NAME | LOAD_STATUS |
+---------------+---------------------+
| tpch.supplier | AVAIL_RPDGSTABSTATE |
| tpch.partsupp | AVAIL_RPDGSTABSTATE |
| tpch.orders | AVAIL_RPDGSTABSTATE |
| tpch.lineitem | AVAIL_RPDGSTABSTATE |
| tpch.nation | AVAIL_RPDGSTABSTATE |
| tpch.customer | AVAIL_RPDGSTABSTATE |
| tpch.region | AVAIL_RPDGSTABSTATE |
| tpch.part | AVAIL_RPDGSTABSTATE |
+---------------+---------------------+
8 rows in set (0.0007 sec)
最后，一些有用的元数据查询SQL参见这里。
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