Redis [QUESTION]Why redis performs so bad in Centos7 & 8

I have a server with esxi6.7,I install Centos6.5, 7.6 ,8.2 on the same server.Then I download redis 5.0.7 and keep default conf.Then I start the redis-server and run redis-benchmark.The result shows centos6 --150000QPS CENTOS7--70000QPS CENTOS8--50000QPS So I want know why redis performs so bad in Centos7 & 8?How can I improve this?

Comment From: yossigo

I wonder if anyone can try to reproduce this on a different environment, same operating systems to validate it's not local to this specific environment (i.e. ESX/VM specific configs, OS image/tuning, etc.).

Comment From: itamarhaber

@yan1990y would you mind cross-posting this to the mailing list so perhaps the folks there would give a hand at reproduction/validation?

Comment From: yan1990y

@yan1990y would you mind cross-posting this to the mailing list so perhaps the folks there would give a hand at reproduction/validation?

After lots of tests,I found the reason:Intel Meltdown and Spectre leaks.The Centos 8 Linux kernel fixs this problem,So the performance go down a lot.

Comment From: yan1990y

I wonder if anyone can try to reproduce this on a different environment, same operating systems to validate it's not local to this specific environment (i.e. ESX/VM specific configs, OS image/tuning, etc.).

After lots of tests,I found the reason:Intel Meltdown and Spectre leaks.The Centos 8 Linux kernel fixs this problem,So the performance go down a lot.

Comment From: oranagra

@yan1990y thanks for looking into this and finding the root cause. Since there's nothing wrong with Redis or anything it could do to mitigate that, i'm closing this ticket. Feel free to re-open if you think otherwise.