[Spice-devel] Unfair comparisons with RDP

[John A. Sullivan III]

On Thu, 2011-06-30 at 10:10 +0300, Yaniv Kaul wrote:
> On 06/30/2011 05:33 AM, John A. Sullivan III wrote:
> > On Wed, 2011-06-29 at 20:22 -0400, Andrew Cathrow wrote:
> >>
> >> ----- Original Message -----
> >>> <snip>
> >>> Hello, all. I've been using both RDP via TSPlus and SPICE for over a
> >>> week now and the practical world results at least in my mode of
> >>> operation are becoming clear. SPICE does handle major screen refreshes
> >>> better, e.g., monstrous graphics or continuously pasting a full line
> >>> of
> >>> text in a full screen notepad. Of course, SPICE is a clear winner when
> >>> it comes to video though still not practically usable on low bandwidth
> >>> links.
> >>>
> >>> However, RDP is trouncing SPICE in the more common day to day tasks
> >>> involving small screen updates. For example, every time I open or
> >>> switch
> >>> my screen to LibreOffice, the tool bar icons seems to pain one at a
> >>> time
> >>> in SPICE where as they appear all at once in TSPlus. Document
> >>> scrolling
> >>> is more immediate and smoother. Surprisingly, when I open the PuTTY
> >>> dialog in SPICE, it paints in sections whereas TSPlus appears all at
> >>> once.
> >> You'll really need to post some real details here - from versions of qemu+spice server that you're using along with the qemu command line syntax, host OS, hardware details through to what's running in the guest, driver versions, etc.
> >>
> >> I've never seen RDP trounce spice, but if it does, then we need some scientific information on the environment so we can diagnose and assist.
> >>
> > <snip>
> > Very happy to do so as we really do want SPICE to become our protocol of
> > choice.  I believe I've posted up our details before but will do so
> > again.
> 
> Would you be so kind as to capture the Spice traffic (using 
> tcpdump/wireshark) and send it over?
> Specifically:
> 1. Please capture from start - before the Spice client connects to the 
> server.
> 2. Ensure you catch full sized packets (-s XXXX - could be 1500 most 
> likely, when using tcpdump)
> 3. Save into file (-w /tmp/file.pcap when using tcpdump)
> 4. Please compress and send / let me know where I can pick it up from.
> 
> I suggest you have only the scenario of connecting to the VM and opening 
> putty, which you complain is slow.
> Hopefully it'll give us some clue.
> TIA,
> Y.
<snip>
Certainly.  On their way in a couple of moments.  If anyone else would
like a copy, please let me know off list.

I took three traces.  The first was our regular SPICE connection.  Then
I took a trace performing the same activities using xfreerdp and TSPlus.
Once again, it was much more responsive and it transferred roughly 1/5th
of the data SPICE did.  I also noticed it said it did not support 32 bit
pixel depth and reverted to 16 although it looked much better than 16.

I then thought, our iSCSI disk access is slow so maybe it was a matter
that all the data was now cached plus the 16 vs 32 bit pixel depth, so I
took another SPICE trace with color-depth=16. It was still much slower
and transferred many times the amount of data.  I'll paste in the timing
notes that are included in the trace tarball.  One can get a anecdotal
sense of how much snappier RDS is from the time lines on doing the exact
same activities:

SPICEStart-20110630 sequence
0 seconds:	start spicec --host 172.x.x.124 --port 5900 --color-depth 32
-to previously painted screen
20:		toggle to full screen
45:		display desktop, i.e., minimize all open applications
64:		Open PuTTY
81:		Paint existing LibreOffice document, i.e., restore from minimize
104:		Start new LibreOffice application after closing previous one
120:		Open LibreOffice document (slowly paints toolbar icons)
136:		toggle away from full screen

Total bytes transfered: 2,687,446


TSPlusStart-20110630 sequence
0 seconds:	start xfreerdp -d MyDomain -a 32 -x lan -z -u myid -f
--plugin cliprdr --plugin rdpsnd 172.29.1.133 & - said it did not
support 32 bit pixel depth and reverted to 16 although it looked much
better than 16 bit
7:		login
17:		display desktop, i.e., minimize all open applications
28:		Open PuTTY
42:		Paint existing LibreOffice document, i.e., restore from minimize
58:		Start new LibreOffice application after closing previous one
75:		Open LibreOffice document (slowly paints toolbar icons)
85:		toggle away from full screen

Total bytes transfered: 562242


SPICEStart-16-20110630 sequence
0 seconds:	start spicec --host 172.x.x.124 --port 5900 --color-depth 16
(Warning: no factory for 8 - I don't know what that message means)
15:		toggle to full screen
39:		login
61:		display desktop, i.e., minimize all open applications
75:		Open PuTTY
92:		Paint existing LibreOffice document, i.e., restore from minimize
114:		Start new LibreOffice application after closing previous one
138:		Open LibreOffice document (slowly paints toolbar icons)
153:		toggle away from full screen

Total bytes transfered: 3643123 (I assume this is higher than 32bit
because of the screen resolution detection when logging in)