Article 5PHB1 lvm raid0 on top of physical raid getting unexpected slow

lvm raid0 on top of physical raid getting unexpected slow

by
wangzw
from LinuxQuestions.org on (#5PHB1)
I have a server with 24 disks and 3 raid card.

I build 4 set of raid as following:

1. Build raid 0+1 with 2 disks on raid card 1 for device sda and mount to /
2. Build raid 5 with 6 disks on raid card 1 for device sdb
3. Build raid 5 with 8 disks on raid card 2 for device sdc
4. Build raid 5 with 8 disks on raid card 3 for device sdd

Create a lvm volume group with sdb sdc and sdd.

Case 1: Create a linear logical volume and do IO test.

Write throughput is 1520 MB/s and %util is 100. Only sdd is writing data and sdc sdb are idle.
This is expected result.

Case 2: Create a striped logical volume with parameters --type raid0 --stripes

Write throughput is only 547 MB/s and %util is around 85. sdb, sdc and sdd are all writing data.

A kernel process named kworker/u128:2 reach 100% CPU usage.

OS is RHEL 7.6, XFS filesystem

Is there anyone getting the same issue and how to solve it?

Thanks in advance.latest?d=yIl2AUoC8zA latest?i=peSOSu4C9P4:bF226n6wb9E:F7zBnMy latest?i=peSOSu4C9P4:bF226n6wb9E:V_sGLiP latest?d=qj6IDK7rITs latest?i=peSOSu4C9P4:bF226n6wb9E:gIN9vFwpeSOSu4C9P4
External Content
Source RSS or Atom Feed
Feed Location https://feeds.feedburner.com/linuxquestions/latest
Feed Title LinuxQuestions.org
Feed Link https://www.linuxquestions.org/questions/
Reply 0 comments