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[Qemu-devel] [Bug 1099403] [NEW] High CPU utilization in vnc mode
From: |
Anuj Kalia |
Subject: |
[Qemu-devel] [Bug 1099403] [NEW] High CPU utilization in vnc mode |
Date: |
Mon, 14 Jan 2013 13:51:18 -0000 |
Public bug reported:
We start a gentoo guest using ./x86-64-softmmu/qemu-x86-64 -hda
<disk>.qcow2 -vnc :6.
Then we start a vncviewer session to this guest from a remote computer.
In this session, we start a video. After starting the video, the CPU
utilization of the guest (the qemu-x86-64 process) increases to about
90%. The high CPU utilization persists even after closing the vncviewer
session.
However, the CPU usage while running a video inside a gentoo guest
(without a remote computer connecting via vncviewer) is only 20-30%. So
we suspect the high CPU usage to be due to the vncserver code running
inside QEMU which has to do a lot of work to send the framebuffer
updates to the client.
My question is why does the usage not decrease when the remote vncviewer
is disconnected? On simple computers (no virtual guests), the CPU usage
of vncserver decreases drastically when the vncviewer client is
disconnected. Why does this not happen in the vncserver provided by QEMU
(through -vnc :6).
** Affects: qemu
Importance: Undecided
Status: New
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https://bugs.launchpad.net/bugs/1099403
Title:
High CPU utilization in vnc mode
Status in QEMU:
New
Bug description:
We start a gentoo guest using ./x86-64-softmmu/qemu-x86-64 -hda
<disk>.qcow2 -vnc :6.
Then we start a vncviewer session to this guest from a remote
computer. In this session, we start a video. After starting the video,
the CPU utilization of the guest (the qemu-x86-64 process) increases
to about 90%. The high CPU utilization persists even after closing the
vncviewer session.
However, the CPU usage while running a video inside a gentoo guest
(without a remote computer connecting via vncviewer) is only 20-30%.
So we suspect the high CPU usage to be due to the vncserver code
running inside QEMU which has to do a lot of work to send the
framebuffer updates to the client.
My question is why does the usage not decrease when the remote
vncviewer is disconnected? On simple computers (no virtual guests),
the CPU usage of vncserver decreases drastically when the vncviewer
client is disconnected. Why does this not happen in the vncserver
provided by QEMU (through -vnc :6).
To manage notifications about this bug go to:
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