Description:
I installed MySQL5.7.23 on a Windows Server 2019 VIRTUAL machine,It starts fine when no other databases or tables are created.When I created more than 100 databases, I used the InnoDB engine,There are about a thousand tables in each database,It will take a long time to start the MySQL service when I close it and start it again,It takes about 30 minutes in my test environment,Two hours in production environment.I didn't see any errors in the log
------------------err.log-------------------
2021-11-16T14:01:00.803802+08:00 0 [Warning] option 'read_buffer_size': unsigned value 0 adjusted to 8192
2021-11-16T14:01:00.804091+08:00 0 [Warning] option 'read_rnd_buffer_size': unsigned value 0 adjusted to 1
2021-11-16T14:01:00.804179+08:00 0 [Warning] TIMESTAMP with implicit DEFAULT value is deprecated. Please use --explicit_defaults_for_timestamp server option (see documentation for more details).
2021-11-16T14:01:00.804239+08:00 0 [Warning] 'NO_ZERO_DATE', 'NO_ZERO_IN_DATE' and 'ERROR_FOR_DIVISION_BY_ZERO' sql modes should be used with strict mode. They will be merged with strict mode in a future release.
2021-11-16T14:01:00.809836+08:00 0 [Note] C:\Program Files\MySQL\MySQL Server 5.7\bin\mysqld.exe (mysqld 5.7.23-log) starting as process 3204 ...
2021-11-16T14:01:00.910778+08:00 0 [Note] InnoDB: Mutexes and rw_locks use Windows interlocked functions
2021-11-16T14:01:00.911700+08:00 0 [Note] InnoDB: Uses event mutexes
2021-11-16T14:01:00.912246+08:00 0 [Note] InnoDB: _mm_lfence() and _mm_sfence() are used for memory barrier
2021-11-16T14:01:00.912986+08:00 0 [Note] InnoDB: Compressed tables use zlib 1.2.3
2021-11-16T14:01:00.915857+08:00 0 [Note] InnoDB: Number of pools: 1
2021-11-16T14:01:00.916928+08:00 0 [Note] InnoDB: Not using CPU crc32 instructions
2021-11-16T14:01:00.922199+08:00 0 [Note] InnoDB: Initializing buffer pool, total size = 2G, instances = 2, chunk size = 128M
2021-11-16T14:01:01.084893+08:00 0 [Note] InnoDB: Completed initialization of buffer pool
2021-11-16T14:01:01.624961+08:00 0 [Note] InnoDB: Highest supported file format is Barracuda.
2021-11-16T14:33:17.708704+08:00 0 [Warning] InnoDB: Resizing redo log from 2*16384 to 2*32768 pages, LSN=540672645
2021-11-16T14:33:17.832268+08:00 0 [Warning] InnoDB: Starting to delete and rewrite log files.
2021-11-16T14:33:17.863322+08:00 0 [Note] InnoDB: Setting log file .\ib_logfile101 size to 512 MB
2021-11-16T14:33:17.867049+08:00 0 [Note] InnoDB: Progress in MB:
100 200 300 400 500
2021-11-16T14:33:18.958389+08:00 0 [Note] InnoDB: Setting log file .\ib_logfile1 size to 512 MB
2021-11-16T14:33:18.960342+08:00 0 [Note] InnoDB: Progress in MB:
100 200 300 400 500
2021-11-16T14:33:19.871499+08:00 0 [Note] InnoDB: Renaming log file .\ib_logfile101 to .\ib_logfile0
2021-11-16T14:33:19.886435+08:00 0 [Warning] InnoDB: New log files created, LSN=540672645
2021-11-16T14:33:33.568248+08:00 0 [Note] InnoDB: Creating shared tablespace for temporary tables
2021-11-16T14:33:33.569872+08:00 0 [Note] InnoDB: Setting file '.\ibtmp1' size to 12 MB. Physically writing the file full; Please wait ...
2021-11-16T14:33:33.615638+08:00 0 [Note] InnoDB: File '.\ibtmp1' size is now 12 MB.
2021-11-16T14:33:33.750584+08:00 0 [Note] InnoDB: 96 redo rollback segment(s) found. 96 redo rollback segment(s) are active.
2021-11-16T14:33:33.753835+08:00 0 [Note] InnoDB: 32 non-redo rollback segment(s) are active.
2021-11-16T14:33:33.757424+08:00 0 [Note] InnoDB: Waiting for purge to start
2021-11-16T14:33:33.829009+08:00 0 [Note] InnoDB: page_cleaner: 1000ms intended loop took 1952688ms. The settings might not be optimal. (flushed=0 and evicted=0, during the time.)
2021-11-16T14:33:33.829605+08:00 0 [Note] InnoDB: 5.7.23 started; log sequence number 540672636
2021-11-16T14:33:33.919767+08:00 0 [Note] InnoDB: Loading buffer pool(s) from C:\ProgramData\MySQL\MySQL Server 5.7\Data\ib_buffer_pool
2021-11-16T14:33:34.025786+08:00 0 [Note] Plugin 'FEDERATED' is disabled.
2021-11-16T14:33:34.025804+08:00 0 [Note] InnoDB: Buffer pool(s) load completed at 211116 14:33:34
2021-11-16T14:33:35.322313+08:00 0 [Warning] Failed to set up SSL because of the following SSL library error: SSL context is not usable without certificate and private key
2021-11-16T14:33:35.332360+08:00 0 [Note] Server hostname (bind-address): '*'; port: 3306
2021-11-16T14:33:35.334645+08:00 0 [Note] IPv6 is available.
2021-11-16T14:33:35.338263+08:00 0 [Note] - '::' resolves to '::';
2021-11-16T14:33:35.339321+08:00 0 [Note] Server socket created on IP: '::'.
2021-11-16T14:33:40.257887+08:00 0 [Note] Event Scheduler: Loaded 0 events
2021-11-16T14:33:40.261208+08:00 0 [Note] C:\Program Files\MySQL\MySQL Server 5.7\bin\mysqld.exe: ready for connections.
Version: '5.7.23-log' socket: '' port: 3306 MySQL Community Server (GPL)
-------------------------end-----------------------------------
I observed that idB files are read during startup,Is there any way to speed up MySQL startup time?
How to repeat:
Create one hundred InnoDB databases with one thousand tables in each database and use separate tablespaces
