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<p class=MsoNormal><font size=2 face=Arial><span lang=EN-US style='font-size:
10.0pt;font-family:Arial'>Hi,<o:p></o:p></span></font></p>
<p class=MsoNormal><font size=2 face=Arial><span lang=EN-US style='font-size:
10.0pt;font-family:Arial'><o:p> </o:p></span></font></p>
<p class=MsoNormal><font size=2 face=Arial><span lang=EN-US style='font-size:
10.0pt;font-family:Arial'>We are encountering a problem of race conditions for
getting VNC port when VM start up.<o:p></o:p></span></font></p>
<p class=MsoNormal><font size=2 face=Arial><span lang=EN-US style='font-size:
10.0pt;font-family:Arial'><o:p> </o:p></span></font></p>
<p class=MsoNormal><font size=2 face=Arial><span lang=EN-US style='font-size:
10.0pt;font-family:Arial'>In a very powerful hypervisor, if we try to start up
more than 1 VM concurrently, then there might be some VMs failed to start up due
to VNC port confilict.<o:p></o:p></span></font></p>
<p class=MsoNormal><font size=2 face=Arial><span lang=EN-US style='font-size:
10.0pt;font-family:Arial'><o:p> </o:p></span></font></p>
<p class=MsoNormal><font size=2 face=Arial><span lang=EN-US style='font-size:
10.0pt;font-family:Arial'>We searched libvirt bugs and found that some one
report the problem and we have give a fix, but the fix can not resolve the
problem.<o:p></o:p></span></font></p>
<p class=MsoNormal><font size=2 face=Arial><span lang=EN-US style='font-size:
10.0pt;font-family:Arial'><o:p> </o:p></span></font></p>
<pre><font size=2 face=Arial><span lang=EN-US style='font-size:10.0pt;
font-family:Arial'><a
href="http://osdir.com/ml/libvir-list/2010-05/msg00530.html">http://osdir.com/ml/libvir-list/2010-05/msg00530.html</a><o:p></o:p></span></font></pre><pre><font
size=2 face=Arial><span lang=EN-US style='font-size:10.0pt;font-family:Arial'><o:p> </o:p></span></font></pre><pre><font
size=2 face=Arial><span lang=EN-US style='font-size:10.0pt;font-family:Arial'><a
href="https://build.opensuse.org/package/view_file?file=vnc-race-3.patch&package=libvirt&project=Virtualization:openSUSE11.3">https://build.opensuse.org/package/view_file?file=vnc-race-3.patch&package=libvirt&project=Virtualization:openSUSE11.3</a><o:p></o:p></span></font></pre><pre><font
size=2 face=Arial><span lang=EN-US style='font-size:10.0pt;font-family:Arial'><o:p> </o:p></span></font></pre><pre><font
size=2 face=Arial><span lang=EN-US style='font-size:10.0pt;font-family:Arial'>The bitmap test-and-set operation is not atomic, so that there still is a time-window in which a VNC port could be reserved for two caller. <o:p></o:p></span></font></pre><pre><font
size=2 face=Arial><span lang=EN-US style='font-size:10.0pt;font-family:Arial'><o:p> </o:p></span></font></pre><pre><font
size=2 face=Arial><span lang=EN-US style='font-size:10.0pt;font-family:Arial'>Your help is highly appreciated!<o:p></o:p></span></font></pre><pre><font
size=2 face=Arial><span lang=EN-US style='font-size:10.0pt;font-family:Arial'><o:p> </o:p></span></font></pre><pre><font
size=2 face=Arial><span lang=EN-US style='font-size:10.0pt;font-family:Arial'>Thanks,<o:p></o:p></span></font></pre>
<p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto;
layout-grid-mode:char'><strong><b><font size=2 color=maroon face=Arial><span
lang=EN-US style='font-size:10.0pt;font-family:Arial;color:maroon'>Guangya Liu</span></font></b></strong><b><font
size=2 color=maroon face=Arial><span lang=EN-US style='font-size:10.0pt;
font-family:Arial;color:maroon;font-weight:bold'><br>
</span></font></b><font size=2 face=Arial><span lang=EN-US style='font-size:
10.0pt;font-family:Arial'>Cloud Developer<br>
<font color=navy><span style='color:navy'>Platform Computing<br>
</span></font>direct: +86-29-87607400-333<br>
<a href="http://www.platform.com/" title="http://www.platform.com/">www.platform.com</a><o:p></o:p></span></font></p>
<p class=MsoNormal><font size=2 face=Arial><span lang=EN-US style='font-size:
10.0pt;font-family:Arial'><o:p> </o:p></span></font></p>
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