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<div class="moz-cite-prefix">On 06/15/2016 08:51 AM, llyzs wrote:<br>
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<blockquote
cite="mid:CACxphuG-8ON9vB9DRcqY1YKGbq7XXsMgwMh4fyaoPd4t-tECzQ@mail.gmail.com"
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<div dir="ltr">Hi Devs,
<div><br>
</div>
<div>I have a virtual PCI device added on VirtualBox OSE and a
driver which sends I/O to do some stuff in the host and
receive interrupts when the work is done. The interrupts work
most of the time, however there are random delays
between PDMDevHlpPCISetIrq is called and the driver ISR is
called. Most of the time there is no delay (<1ms) but
periodically there is a delay from 10+ms to even 60+ms. One
more strange thing is that the delay mostly happen at exactly
every 500ms. <span style="line-height:1.5">So anyone can give
me some hint on what is causing the interrupt delay? What
kind of job inside VirtualBox that runs every 500ms that
might be causing interrupt delay?</span></div>
<div><br>
</div>
<div>I am on Windows 8.1 x64 (both guest and host). Thanks in
advanced.<br>
</div>
<div><br>
</div>
</div>
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<br>
Just curious, have you tried this with the VirtualBox 5.1 beta? The
APIC and I/O APIC implementations in VirtualBox were completely
re-done and it resulted in fixing long-standing problems of the
nature you describe (for e.g., EOI on level-triggered interrupts not
causing the I/O APIC to immediately pickup pending interrupts until
another interrupt arrives and a few others problems).<br>
<br>
<br>
Regards,<br>
Ram.<br>
<br>
<br>
<blockquote
cite="mid:CACxphuG-8ON9vB9DRcqY1YKGbq7XXsMgwMh4fyaoPd4t-tECzQ@mail.gmail.com"
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<div dir="ltr">
<div>Vic</div>
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