Re: [Qemu-devel] [PATCH 4/5] uhci: rewrite UHCI emulator, fully async operation with multiple outstanding transactions

[andrzej zaborowski]

2008/10/15 Max Krasnyansky <address@hidden>:
> Hi Juergen,
>
> Juergen Lock wrote:
>>
>> This is whats got committed as r5050, right?  It causes a large slowdown
>> with some linux guests, as posted here:
>>        http://lists.gnu.org/archive/html/qemu-devel/2008-09/msg01201.html
>> As mentioned the guest I tested was:
>>        sidux-2008-03-ourea-pre1-kde-lite-i386-200809142136.iso
>> It uses a Linux 2.6.26 kernel, a FreeBSD guest is not affected by the
>> slowness, could this be related to dynticks?
>>
>>  Oh and on one box transfers over the emulated usb nic even sometimes
>> stall, I have to ping the guest's ip for them to continue, and the ping
>> then loses packets too.
>
> Can you please clarify your setup. As I understood, from the thread you
> mentioned above, you're running Linux 2.6.26 guest on QEMU under FreeBSD
> host,correct ?

For the record on Linux host I observed the same issues.  Juergen
mentioned that in an earlier mail.  The transfer rate is about 60kB/s
reading from an emulated mass storage device using a raw image.  It
was before about 1MB/s according to Juergen.  I wasn't using dynticks.

Cheers