Bug 1131788

Summary: blkdeviotune should can be used in session mode
Product: Red Hat Enterprise Linux 7 Reporter: Luyao Huang <lhuang>
Component: libvirtAssignee: Martin Kletzander <mkletzan>
Status: CLOSED ERRATA QA Contact: Virtualization Bugs <virt-bugs>
Severity: medium Docs Contact:
Priority: medium    
Version: 7.1CC: dyuan, lhuang, mkletzan, mzhan, pzhang, rbalakri
Target Milestone: rc   
Target Release: ---   
Hardware: x86_64   
OS: All   
Whiteboard:
Fixed In Version: libvirt-1.2.8-1.el7 Doc Type: Bug Fix
Doc Text:
Story Points: ---
Clone Of: Environment:
Last Closed: 2015-03-05 07:42:44 UTC Type: Bug
Regression: --- Mount Type: ---
Documentation: --- CRM:
Verified Versions: Category: ---
oVirt Team: --- RHEL 7.3 requirements from Atomic Host:
Cloudforms Team: --- Target Upstream Version:
Embargoed:

Description Luyao Huang 2014-08-20 05:21:29 UTC 
Description of problem:
blkdeviotune should can be used in session mode

Version-Release number of selected component (if applicable):
libvirt-1.2.7-1.el7.x86_64

How reproducible:
100%

Steps to Reproduce:
$ virsh uri
qemu:///session


$ virsh blkdeviotune sdsd hda 1
error: Unable to change block I/O throttle
error: unsupported configuration: Block I/O tuning is not available in session mode


Actual results:
blkdeviotune can't be used in session mode in RHEL7

Expected results:
blkdeviotune can be used in session mode

Additional info:
Comment 2 Martin Kletzander 2014-08-20 05:29:47 UTC 
Fixed upstream with v1.2.7-157-g7d9def2:

commit 7d9def2ec1afaf50ec680f2aadfe359cb1ba5b80
Author: Martin Kletzander <mkletzan>
Date:   Fri Aug 15 14:35:53 2014 +0200

    qemu: allow device block I/O tuning in session mode
Comment 4 zhengqin 2014-09-15 05:15:08 UTC 
Although there is an bug https://bugzilla.redhat.com/show_bug.cgi?id=927369 to block to verify this issue, from the bug 927369, there is a workround by creating directory "$HOME/.cache/libvirt"


Verify this issue with this workaround and build libvirt-1.2.8-2.el7.x86_64:

[test@rhel7-a1 ~]$  virsh blkdeviotune rhel6 hda 2

[test@rhel7-a1 ~]$  virsh blkdeviotune rhel6 hda 
total_bytes_sec: 2
read_bytes_sec : 0
write_bytes_sec: 0
total_iops_sec : 0
read_iops_sec  : 0
write_iops_sec : 0

[test@rhel7-a1 ~]$  virsh blkdeviotune rhel6 hda 3

[test@rhel7-a1 ~]$  virsh blkdeviotune rhel6 hda 
total_bytes_sec: 3
read_bytes_sec : 0
write_bytes_sec: 0
total_iops_sec : 0
read_iops_sec  : 0
write_iops_sec : 0
Comment 5 Pei Zhang 2014-10-17 03:44:42 UTC 
Verify vision:
kernel-3.10.0-188.el7.x86_64
qemu-kvm-rhev-2.1.2-3.el7.x86_64
libvirt-1.2.8-5.el7.x86_64

steps:

1.
add a user and switch to user mode.
[test@184 images]$ virsh uri
qemu:///session

2.
using blkdeviotune query a block device I/O tuning parameters
[test@184 images]$ virsh blkdeviotune rhel7 vda
total_bytes_sec: 0
read_bytes_sec : 0
write_bytes_sec: 0
total_iops_sec : 0
read_iops_sec  : 0
write_iops_sec : 0

3.
using blkdeviotune set a block device I/O tuning parameters
[test@184 images]$ virsh blkdeviotune rhel7 vda 5

[test@184 images]$ virsh blkdeviotune rhel7 vda
total_bytes_sec: 5
read_bytes_sec : 0
write_bytes_sec: 0
total_iops_sec : 0
read_iops_sec  : 0
write_iops_sec : 0

4.
set --total-bytes-sec
[test@184 images]$ virsh blkdeviotune r7new hda --total-bytes-sec 100

[test@184 images]$ virsh blkdeviotune r7new hda 
total_bytes_sec: 100
read_bytes_sec : 0
write_bytes_sec: 0
total_iops_sec : 0
read_iops_sec  : 0
write_iops_sec : 100

set --read-bytes-sec
[test@184 images]$ virsh blkdeviotune r7new hda --read-bytes-sec 200

[test@184 images]$ virsh blkdeviotune r7new hda 
total_bytes_sec: 0
read_bytes_sec : 200
write_bytes_sec: 0
total_iops_sec : 0
read_iops_sec  : 0
write_iops_sec : 0

set --write-bytes-sec
[test@184 images]$ virsh blkdeviotune r7new hda --write-bytes-sec 300

[test@184 images]$ virsh blkdeviotune r7new hda 
total_bytes_sec: 0
read_bytes_sec : 0
write_bytes_sec: 300
total_iops_sec : 0
read_iops_sec  : 0
write_iops_sec : 0

set --total-iops-sec
[test@184 images]$ virsh blkdeviotune r7new hda --total-iops-sec 400

[test@184 images]$ virsh blkdeviotune r7new hda 
total_bytes_sec: 0
read_bytes_sec : 0
write_bytes_sec: 300
total_iops_sec : 400
read_iops_sec  : 0
write_iops_sec : 0

set --read-iops-sec
[test@184 images]$ virsh blkdeviotune r7new hda --read-iops-sec 500

[test@184 images]$ virsh blkdeviotune r7new hda 
total_bytes_sec: 0
read_bytes_sec : 0
write_bytes_sec: 300
total_iops_sec : 0
read_iops_sec  : 500
write_iops_sec : 0

set --write-iops-sec
[test@184 images]$ virsh blkdeviotune r7new hda --write-iops-sec 600

[test@184 images]$ virsh blkdeviotune r7new hda 
total_bytes_sec: 0
read_bytes_sec : 0
write_bytes_sec: 300
total_iops_sec : 0
read_iops_sec  : 0
write_iops_sec : 600

5.
using blkdeviotune set a block device I/O tuning parameters with options

--config
[test@184 images]$ virsh blkdeviotune rhel7 vda 3 --config

[test@184 images]$ virsh blkdeviotune rhel7 vda
total_bytes_sec: 5
read_bytes_sec : 0
write_bytes_sec: 0
total_iops_sec : 0
read_iops_sec  : 0
write_iops_sec : 0

[test@184 images]$ virsh destroy rhel7 ; virsh start rhel7
Domain rhel7 destroyed

Domain rhel7 started

[test@184 images]$ virsh blkdeviotune rhel7 vda
total_bytes_sec: 3               ------- reboot guest , this parameter was set.
read_bytes_sec : 0
write_bytes_sec: 0
total_iops_sec : 0
read_iops_sec  : 0
write_iops_sec : 0


--live
[test@184 images]$ virsh blkdeviotune r7new hda --write-iops-sec 500 --live

[test@184 images]$ virsh blkdeviotune r7new hda
total_bytes_sec: 100
read_bytes_sec : 0
write_bytes_sec: 0
total_iops_sec : 0
read_iops_sec  : 0
write_iops_sec : 500
 
--current (domain is running)
[test@184 images]$ virsh blkdeviotune r7new hda --read-bytes-sec 900 --current

[test@184 images]$ virsh blkdeviotune r7new hda
total_bytes_sec: 0
read_bytes_sec : 900   ----900 was set
write_bytes_sec: 0
total_iops_sec : 0
read_iops_sec  : 0
write_iops_sec : 500

--current (domain is shut off)
[test@184 images]$ virsh blkdeviotune r7new hda --write-bytes-sec 400 --current

[test@184 images]$ virsh start r7new
Domain r7new started

[test@184 images]$ virsh blkdeviotune r7new hda
total_bytes_sec: 0
read_bytes_sec : 0
write_bytes_sec: 400    ----400 was set
total_iops_sec : 0
read_iops_sec  : 0
write_iops_sec : 100


6.
check setting only one value  resets the other two in that category to unlimited.
[test@184 images]$ virsh blkdeviotune rhel7 vda  --read-bytes-sec 10 --write-bytes-sec 20

[test@184 images]$ virsh blkdeviotune rhel7 vda
total_bytes_sec: 0     ----- total was reset to 0
read_bytes_sec : 10    -----read was set
write_bytes_sec: 20    -----write was set
total_iops_sec : 0
read_iops_sec  : 0
write_iops_sec : 0

7.
check Bytes and iops values are independent
[test@184 images]$ virsh blkdeviotune rhel7 vda  --read-bytes-sec 10 --write-iops-sec 10
[test@184 images]$ virsh blkdeviotune rhel7 vda
total_bytes_sec: 0
read_bytes_sec : 10
write_bytes_sec: 0
total_iops_sec : 0
read_iops_sec  : 0
write_iops_sec : 10

8.
negative testing

--check total_bytes_sec cannot appear with read_bytes_sec or write_bytes_sec.

[test@184 images]$ virsh blkdeviotune rhel7 vda --config --live --read-bytes-sec 10 --total-bytes-sec 1
error: Unable to change block I/O throttle
error: invalid argument: total and read/write of bytes_sec cannot be set at the same time

--check check total_iops_sec cannot appear with read_iops_sec or write_iops_sec.

[test@184 images]$ virsh blkdeviotune rhel7 vda --live --read-bytes-sec 10 --write-bytes-sec 30 --total-iops-sec 1 --read-iops-sec 10
error: Unable to change block I/O throttle
error: invalid argument: total and read/write of iops_sec cannot be set at the same time
Comment 7 errata-xmlrpc 2015-03-05 07:42:44 UTC 
Since the problem described in this bug report should be
resolved in a recent advisory, it has been closed with a
resolution of ERRATA.

For information on the advisory, and where to find the updated
files, follow the link below.

If the solution does not work for you, open a new bug report.

https://rhn.redhat.com/errata/RHSA-2015-0323.html