TiDB 7.4 Cluster Deployment Successful, TiFlash Fails to Start When Launching Cluster

Note:
This topic has been translated from a Chinese forum by GPT and might contain errors.

Original topic: tidb7.4部署集群成功,启动集群是ti-flash无法启动。

| username: 哈喽沃德

[TiDB Usage Environment] Test
[TiDB Version] 7.4.0
[Encountered Problem: Problem Phenomenon and Impact]


The above error occurs during safe startup, and the specific log is as follows:

[root@localhost ~]# cd /data/tidb-deploy/tiflash-9000/log
[root@localhost log]# ll
Total 4
-rw-r–r-- 1 tidb tidb 1140 Oct 30 09:28 tiflash_stderr.log
[root@localhost log]# cat tiflash_stderr.log
Fail to check CPU flags: avx2 not supported. Require avx2 popcnt movbe.
Fail to check CPU flags: avx2 not supported. Require avx2 popcnt movbe.
Fail to check CPU flags: avx2 not supported. Require avx2 popcnt movbe.
Fail to check CPU flags: avx2 not supported. Require avx2 popcnt movbe.
Fail to check CPU flags: avx2 not supported. Require avx2 popcnt movbe.
Fail to check CPU flags: avx2 not supported. Require avx2 popcnt movbe.
Fail to check CPU flags: avx2 not supported. Require avx2 popcnt movbe.
Fail to check CPU flags: avx2 not supported. Require avx2 popcnt movbe.
Fail to check CPU flags: avx2 not supported. Require avx2 popcnt movbe.
Fail to check CPU flags: avx2 not supported. Require avx2 popcnt movbe.
Fail to check CPU flags: avx2 not supported. Require avx2 popcnt movbe.
Fail to check CPU flags: avx2 not supported. Require avx2 popcnt movbe.
Fail to check CPU flags: avx2 not supported. Require avx2 popcnt movbe.
Fail to check CPU flags: avx2 not supported. Require avx2 popcnt movbe.
Fail to check CPU flags: avx2 not supported. Require avx2 popcnt movbe.
[root@localhost log]#

| username: 裤衩儿飞上天 | Original post link

TiFlash Overview | PingCAP Documentation Center

| username: Miracle | Original post link

Does this depend on the CPU model?
I didn’t see anything in the documentation about not supporting AVX2. What should I do, replace the CPU?

| username: TiDBer_小阿飞 | Original post link

The CPU instruction set is incorrect, it must support AVX2.

| username: 像风一样的男子 | Original post link

TiFlash requires support for the AVX2 instruction set.

| username: 裤衩儿飞上天 | Original post link

  1. You can just change the configuration of the virtual machine. Specifically, you can look it up based on your virtual software.
  2. Most physical machine CPUs support it, unless it’s a particularly old machine. If it doesn’t support it, then it just doesn’t support it.
| username: 哈喽沃德 | Original post link

No wonder, I was wondering why the single-node cluster deployed on another machine is supported, but it doesn’t work when divided into three virtual machines. If I want to move TiFlash to another machine now, what operations are needed for the currently deployed cluster? Do I need to uninstall it?

| username: 哈喽沃德 | Original post link

If the physical host does not support the AVX2 instruction set, then the virtual machine cannot modify it either, right?

| username: Fly-bird | Original post link

The CPU is not supported, change the CPU :grinning:

| username: 裤衩儿飞上天 | Original post link

That’s right… But now almost all of them are supported. Machines that are not supported are at least ten years old or more.

| username: 裤衩儿飞上天 | Original post link

If the software is already installed, you can directly scale down.

| username: 哈喽沃德 | Original post link

The software deployment is complete. To scale down, you just need to remove TiFlash, right?

| username: Miracle | Original post link

:+1: :+1: :+1:, learned something new.

| username: tidb菜鸟一只 | Original post link

Scale down the current TiFlash and then scale it up on machines that support AVX2.

| username: 裤衩儿飞上天 | Original post link

Yes~~

| username: zhanggame1 | Original post link

The CPU is too old, probably from 10 years ago.

| username: Aionn | Original post link

It suggests trying to use a virtual machine.
| username: 哈喽沃德 | Original post link

Yes, it is indeed a server replaced from a previous project.

| username: 哈喽沃德 | Original post link

It is now a virtual machine, which should be related to the CPU of the host machine.

| username: TiDBer_小阿飞 | Original post link

It’s probably a bit old, haha! If the physical environment doesn’t support it, can the virtual machine environment set the CPU instruction set? Have you tested it?