Bug 1119171 - The value of steal time in RHEL7.1 guest becomes "0.0 st" after S3
Summary: The value of steal time in RHEL7.1 guest becomes "0.0 st" after S3
Keywords:
Status: CLOSED WONTFIX
Alias: None
Product: Red Hat Enterprise Linux 7
Classification: Red Hat
Component: qemu-kvm
Version: 7.1
Hardware: x86_64
OS: Linux
medium
medium
Target Milestone: rc
: ---
Assignee: Amit Shah
QA Contact: Virtualization Bugs
URL:
Whiteboard:
Depends On:
Blocks: Virt-S3/S4-7.0
TreeView+ depends on / blocked
 
Reported: 2014-07-14 08:16 UTC by huiqingding
Modified: 2015-03-04 06:04 UTC (History)
6 users (show)

Fixed In Version:
Doc Type: Bug Fix
Doc Text:
Clone Of:
Environment:
Last Closed: 2015-03-04 06:04:55 UTC


Attachments (Terms of Use)

Description huiqingding 2014-07-14 08:16:05 UTC
Description of problem:
Boot two RHEL7.1 guests with "-smp 1", bonding cpu of these two guests to one same host cpu. Add 100% cpu load in guest, use top command to check steal time in two guests, found the steal time is about "50%". Do S3 inside guest, after resume, the steal time becomes "0.0"

Version-Release number of selected component (if applicable):
Host side:
kernel-3.10.0-133.el7.x86_64
qemu-kvm-1.5.3-66.el7.x86_64
Guest side:
kernel-3.10.0-133.el7.x86_64

How reproducible:
100%

Steps to Reproduce:
1.Boot two guests using the following commands:

# taskset -c 1 /usr/libexec/qemu-kvm -cpu SandyBridge \
-enable-kvm  -m 2G  -smp 1,maxcpus=160 \
-monitor stdio \
-M pc \
-global PIIX4_PM.disable_s3=0 \
-global PIIX4_PM.disable_s4=0 \
-drive file=/home/rhel7-64-ga.qcow2,if=none,id=drive-scsi-disk,format=qcow2,cache=none,werror=stop,rerror=stop \
-device virtio-scsi-pci,id=scsi0,addr=0x4 \
-device scsi-hd,drive=drive-scsi-disk,bus=scsi0.0,id=data-disk2,bootindex=0 \
-netdev tap,id=hostnet0,vhost=on,id=hostnet0,script=/etc/qemu-ifup \
-device virtio-net-pci,netdev=hostnet0,id=virtio-net-pci0,mac=c2:9a:2f:9c:de:10,bus=pci.0,addr=0x5 \
-qmp tcp:0:4445,server,nowait \
-spice port=5901,password=redhat-vga,disable-ticketing -vga qxl -global qxl-vga.vram_size=33554432

2. Add 100% cpu load in two guests
# for ((;;)) do x=1; done

3. Inside two guests, run top command to check steal time value.

4. Inside two guests, do S3
# pm-suspend

5. After resuming the guest, run top command to check steal time value.

Actual results:
after step3, the steal time of two guests are about 50%
after step5, the steal time of two guests are 0.0

Expected results:
after step5, the steal time of two guests should be about 50%

Additional info:

Comment 1 huiqingding 2014-07-14 08:30:12 UTC
I also test the following version, also hit this problem:
Host side:
kernel-3.10.0-125.el7.x86_64
qemu-kvm-1.5.3-66.el7.x86_64
Guest side:
kernel-3.10.0-125.el7.x86_64

and
Host side:
kernel-3.10.0-124.el7.x86_64
qemu-kvm-1.5.3-66.el7.x86_64
Guest side:
kernel-3.10.0-124.el7.x86_64

Best regards
Huiqing

Comment 2 huiqingding 2014-07-14 08:34:37 UTC
Please note:

I also tried rhel7.0.z build as well, also hit this problem:
Host side:
kernel-3.10.0-123.6.2.el7.x86_64
qemu-kvm-1.5.3-66.el7.x86_64
Guest side:
kernel-3.10.0-123.6.2.el7.x86_64


Best regards
Huiqing


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