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Reference: https://smalldatum.blogspot.com/2026/04/cpu-bound-sysbench-on-large-server.html Issue: ps-covered-pk - select id from sbtest where id in ( 100 random ids) , regressed between 10.5.29 release to 10.4.34 release Conclusion: "Remove multiple InnoDB buffer pool instances (MDEV-15058)" commit: 1a6f708ec594ac0ae2dd30db926ab07b100fa24b , did cause regression in ps-ps-covered-pk Investigation: Two major changes AHI=OFF and BP instance=1 ( hard coded) were put in 10.5.29 which could have impacted ps-covered-id. AHI=on does improve qps by 5-10% in case of ps-covered-id but I kept AHI=off for comparison of 10.4 vs 10.5 upto 10% regression , I am able to get on 6 core laptop with BP=2 GB , PFS=1 and other min config Article content I used Dimstat to monitor detail and found that cpu% utilization were roughly similar for 10.4 and 10.5 as you can see in below graph Article content Now, the question was why qps was less for 16 thread when hit 100% cpu. In order to ...

While testing of mysql using sysbench I wanted to ensure that sysbench client is using SSL connection. For this  performance_schema came handy. mysql> SELECT CONNECTION_TYPE from performance_schema.threads where processlist_command='Query'; +-----------------+ | CONNECTION_TYPE | +-----------------+ | SSL/TLS         | +-----------------+ mysql> desc performance_schema.threads ; +---------------------+---------------------+------+-----+---------+-------+ | Field               | Type                | Null | Key | Default | Extra | +---------------------+---------------------+------+-----+---------+-------+ | THREAD_ID           | bigint(20) unsigned | NO   | PRI | NULL    |       | | NAME                | varchar(128)        | NO...