slow paints despite fast hardware

[Phlip]

CygWinners:

I have either Ubuntu or Mandriva on an old Dell Latitude. Alone, it's
perfectly fast. Some programs are faster than on my modern clone
running WinXP. Big surprise there.

However, when I run the latest CygWin XFree on WinXP, and connect
directly to this notebook with SSH, repaints are slow. I can run
Konsole, enter 'ls', and watch each line repaint, from left to right,
as the console scrolls.

This is probably a FAQ, but "slow" is kind'a hard to Google for these days.

Only painting is slow, as if the system must fetch each pixel, and is
missing some buffering or hardware acceleration on the WinXP side. All
other data transfers are super-fast, on a local Ethernet. Further, the
Linux X-server, with a remote client in another city, is super-fast.

This experience tells me that I simply don't know /what/ I don't know
about the XFree config files. Is there an entry somewhere that just
says 'fast = no', so I can switch that to 'yes'?

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Re: slow paints despite fast hardware

[Larry Hall (Cygwin X)]

Phlip wrote:

CygWinners:

I have either Ubuntu or Mandriva on an old Dell Latitude. Alone, it's
perfectly fast. Some programs are faster than on my modern clone
running WinXP. Big surprise there.

However, when I run the latest CygWin XFree on WinXP, and connect
directly to this notebook with SSH, repaints are slow. I can run
Konsole, enter 'ls', and watch each line repaint, from left to right,
as the console scrolls.

This is probably a FAQ, but "slow" is kind'a hard to Google for these days.

Only painting is slow, as if the system must fetch each pixel, and is
missing some buffering or hardware acceleration on the WinXP side. All
other data transfers are super-fast, on a local Ethernet. Further, the
Linux X-server, with a remote client in another city, is super-fast.

This experience tells me that I simply don't know /what/ I don't know
about the XFree config files. Is there an entry somewhere that just
says 'fast = no', so I can switch that to 'yes'?




Yes of course!  But I would recommend setting "fast = super".  It's really
the best option.  "fast = yes" is for the mundane.  Also, keep in mind that
a goal of Cygwin-X is to run things as slowly as possible but to add Cygwin
specific flags and patches anywhere possible to allow people to configure it
in hopefully very obtuse terms to run more quickly.  Without this added
complication, just about anyone could figure out how to run the X server
easily, which would then eliminate the need for this list.  No one wants that!

In all seriousness, if you really think that your question could be a FAQ,
why wouldn't you start with the Cygwin-X FAQ?  For example, the answer to
your problem may come from the following entry:



Or perhaps something else listed in the FAQ would prove helpful.  If not,
please read and follow the problem reporting guidelines found here:



before posting any follow-up.  It will help you provide some information
that may allow others to assist you in pinpointing your problem.

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Re: slow paints despite fast hardware

[Phlip]

Larry Hall (Cygwin X) wrote:


In all seriousness, if you really think that your question could be a FAQ,
why wouldn't you start with the Cygwin-X FAQ?  For example, the
answer to
your problem may come from the following entry:


Thanks for the derision and RTFM. I already stated I have fast network
conductivity, which is all those FAQ entries point out.

In my year of experience with GUIs and their hardware (repeated 20
times), I have learned that some programs default to the safest
possible options at install time; options which are perforce slow. So
this makes me think I can find some method to directly specify the
acceleration options, such as server-side caching, or drivers that
work closer to my graphics card. I do not know where to even start
looking for such things.

Again, why should Linux->Win32 be slow when Linux->cloud->Linux is so fast?

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Re: slow paints despite fast hardware

[Larry Hall (Cygwin X)]

Phlip wrote:

Larry Hall (Cygwin X) wrote:

In all seriousness, if you really think that your question could be a 
FAQ,

why wouldn't you start with the Cygwin-X FAQ?  For example, the
answer to
your problem may come from the following entry:


Thanks for the derision and RTFM. I already stated I have fast network
conductivity, which is all those FAQ entries point out.



Did you even read the FAQ entry I pointed to?  It says nothing about
needing a "fast network".



In my year of experience with GUIs and their hardware (repeated 20
times), I have learned that some programs default to the safest
possible options at install time; options which are perforce slow. So
this makes me think I can find some method to directly specify the
acceleration options, such as server-side caching, or drivers that
work closer to my graphics card. I do not know where to even start
looking for such things.

Again, why should Linux->Win32 be slow when Linux->cloud->Linux is so fast?



I don't know what you mean by "Linux->Win32" but Windows is not Linux and
neither is Cygwin.

I've provided you with some pointers on things that you should look into
and consider and follow-up information that you should provide if following
those leads doesn't provide positive results.  You are, of course, free to
ignore any of this info and follow your own instinct.  I can't offer
anything to help you in that regard beyond saying that Cygwin-X is not
configured to be unoptimized at install time (I'm assuming that's what you
mean by "perforce" flow - I really don't get the reference).  If it were
configured to be slow at installation time, then your presumption that this
issue would be a FAQ would, again, be a good one which would be all the more
reason to look to the FAQ for answers.  It would also tend to lead to an
explosion of reports on this list about poor performance, which is not the
case if you take a quick browse of the email archives (though there are
certainly some who have such complaints, thus the FAQ entry - I'm getting
the feeling that all this logic is causing me to loop infinitely. ;-) )



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Re: slow paints despite fast hardware

[Phlip]

Larry Hall (Cygwin X) wrote:


> Again, why should Linux->Win32 be slow when Linux->cloud->Linux
> is so fast?



I don't know what you mean by "Linux->Win32" but Windows is not
Linux and neither is Cygwin.


I'm having trouble feeling motivated to continue reading your posts
after such condescension. In context, it obviously meant this:

a Linux workstation -> an X client -> TCP/IP -> Ethernet -> a Win32
workstation -> TCP/IP -> XWin.exe -> X-Windows server -> display
hardware.

Do I have to, like, deconstruct each stack for you?

(Incidentally, the FAQ entry you indicated had trouble displaying
correctly in Internet Explorer. And the page is too long. In my
experience, IE gets # markers correct in long pages, compared to other
browsers, so don't blame IE...)

I suspect you mean this entry:

"7.7. Cygwin/X has very poor performance. What's the reason?

"Most likely you have installed some kind of personal firewall..."

Well, besides I already told you that other network activity was fast,
I have both Mandriva's and MS's built-in firewalls, and they are
correctly tuned. When I turn them off, and the virus scanner, the
problem remains.

You will not need to read my posts here anymore if you would reveal
the names of the config files, and their setting lines, that tune the
display hardware for XWin.exe. Then I would not need to Google for the
word "slow", which is too broad a search.

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Re: slow paints despite fast hardware

[Larry Hall (Cygwin X)]

Phlip wrote:

Larry Hall (Cygwin X) wrote:


> Again, why should Linux->Win32 be slow when Linux->cloud->Linux
> is so fast?



I don't know what you mean by "Linux->Win32" but Windows is not
Linux and neither is Cygwin.


I'm having trouble feeling motivated to continue reading your posts
after such condescension. In context, it obviously meant this:

a Linux workstation -> an X client -> TCP/IP -> Ethernet -> a Win32
workstation -> TCP/IP -> XWin.exe -> X-Windows server -> display
hardware.

Do I have to, like, deconstruct each stack for you?

(Incidentally, the FAQ entry you indicated had trouble displaying
correctly in Internet Explorer. And the page is too long. In my
experience, IE gets # markers correct in long pages, compared to other
browsers, so don't blame IE...)

I suspect you mean this entry:

"7.7. Cygwin/X has very poor performance. What's the reason?

"Most likely you have installed some kind of personal firewall..."

Well, besides I already told you that other network activity was fast,
I have both Mandriva's and MS's built-in firewalls, and they are
correctly tuned. When I turn them off, and the virus scanner, the
problem remains.

You will not need to read my posts here anymore if you would reveal
the names of the config files, and their setting lines, that tune the
display hardware for XWin.exe. Then I would not need to Google for the
word "slow", which is too broad a search.



Clearly you're annoyed that someone (or in particular me) will not just
provide you with the information you want.  I've been trying to tell you
that you're proceeding from a false supposition and that, in fact, the
information you're looking for doesn't exist.  But I guess I've also made
an incorrect assumption.  I thought you were having a problem using
Cygwin-X and wanted to engage people on this list to try to find a
solution.  I realize now I was wrong.  My bad.  I apologize to others
on the list for extending this thread and adding to the volume in your
mail boxes.  It was clearly unnecessary.

Good luck to you, Phlip, in your pursuit of a solution to your problem.

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Re: slow paints despite fast hardware

[Phlip]

Larry Hall (Cygwin X) wrote:


I apologize to others
on the list for extending this thread and adding to the volume in your
mail boxes.  It was clearly unnecessary.


Don't forget apologizing for leaving a dead trail in the archives...

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Re: slow paints despite fast hardware

[Larry Hall (Cygwin X)]

Phlip wrote:

Larry Hall (Cygwin X) wrote:


I apologize to others
on the list for extending this thread and adding to the volume in your
mail boxes.  It was clearly unnecessary.


Don't forget apologizing for leaving a dead trail in the archives...



Actually, I've done all the apologizing I intend to in this thread.

Again, I hope you are successful at finding a resolution to your problem.

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Re: slow paints despite fast hardware

[Christopher Faylor]

On Sat, Aug 26, 2006 at 07:10:52PM -0700, Phlip wrote:
>Larry Hall (Cygwin X) wrote:
>>I apologize to others on the list for extending this thread and adding
>>to the volume in your mail boxes.  It was clearly unnecessary.
>
>Don't forget apologizing for leaving a dead trail in the archives...

On the contrary, this is a good illustration for anyone who tends to
become offended by attempts to clarify and redirect false assumptions.

It should illustrate that, when requesting help, there is some benefit
to carefully thinking about problems and maintaining an open mind plus a
certain degree of humbleness.  After all, if you were really a genius at
the things you're asking about, you wouldn't need help at all would you?

When one needs help, it would seem to make sense to approach the process
of asking for help with implied gratefulness rather than overt
arrogance.  Otherwise, you stand the chance of people interpreting your
actions in such a way as to decide that helping you is not worth the
effort.

Maybe that's not the exact outcome someone reading this thread in the
archives would hope for but it is, IMO, a valuable lesson nonetheless.
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Cygwin Co-Project Leader[EMAIL PROTECTED]
TimeSys, Inc.

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Re: slow paints despite fast hardware

[Phlip]

Christopher Faylor wrote:


On the contrary, this is a good illustration for anyone who tends to
become offended by attempts to clarify and redirect false assumptions.


The fallout makes converging on an answer much harder too.

Let's start again, with a parable. For example, if I discovered the
CrystalSpace shader were slow, their FAQs and forums would tell me to
switch from the emulation shader to the hardware shader. They would
tell me to inspect such-and-so log file to find evidence, to obtain
such-and-so driver, and to change such-and-so configuration file.

CrystalSpace ships with the software emulator enabled because you
obviously might not have the same hardware as their build server has.
So this default is safe, not fast.

If they said, "Did you even read the FAQ?", I would read it, report
that I did, and report how well I could apply its suggestions. If they
said, "hey newb, is your computer turned on?"... what would you
answer?

My Cygwin's X server generates the slowest GUIs on my workstation. The
rest handle simple repaints in user-time. I have observed this
problem, off and on, over several different platforms and
configurations, for over a year by now, and it has limited my ability
to make Cygwin productive. The problem's tenacity makes me think it is
commonly reported and easy to fix. My inability to read the various
xinitrc-related batch files, and to Google for their documentation and
online FAQs, has told me simply that there is something that I don't
know how to even ask about.

So I ask my question as a metaphor. Because I have experience with GUI
systems that ship in a safe configuration, instead of the fast
configuration, I ask if this is the case for Cygwin's X server.

Things go downhill from there, but I'm not sure if any better metaphor
were possible...

The question remains: Where do I start the investigate, and what RC
files and setting lines might control the situation?

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Re: slow paints despite fast hardware

[Peter Woo]

Phlip wrote:
> The question remains: Where do I start the investigate, and what RC
> files and setting lines might control the situation?
My understanding is that Cygwin is just an emulator.  Cygwin/X will
respect the hardware acceleration that you do on the Windows config. 
So, if your Windows has been configured to make full use of the video
hardware acceleration, so does Cygwin/X automatically.  Most of the
cryptic xf86config that you see on Linux is not applicable to Cygwin.

I guess I am confused like the other folks on what else you could do to
tune up Cygwin/X.  Just to limit the scope a bit - do you run slow xterm
even just by opening up a local xterm on your Windows XP (display
127.0.0.1:0.0)?

Cheers,
P.

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Re: slow paints despite fast hardware

[Phlip]

Peter Woo wrote:


Most of the
cryptic xf86config that you see on Linux is not applicable to Cygwin.


Yay


I guess I am confused like the other folks on what else you could do to
tune up Cygwin/X.  Just to limit the scope a bit - do you run slow xterm
even just by opening up a local xterm on your Windows XP (display
127.0.0.1:0.0)?


The local xterm (the one that anchors the server) is fast.

 Remote Konsole - super slow
 Remote Gedit - slow
 Remote Xterm - fast!

At a guess, are some programs pushing pixels across the wire, to
assemble text, while some programs use the local fonts?

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Re: slow paints despite fast hardware

[Cary Jamison]

Phlip wrote:
> Peter Woo wrote:
>
>> Most of the
>> cryptic xf86config that you see on Linux is not applicable to Cygwin.
>
> Yay
>
>> I guess I am confused like the other folks on what else you could do
>> to tune up Cygwin/X.  Just to limit the scope a bit - do you run
>> slow xterm even just by opening up a local xterm on your Windows XP
>> (display 127.0.0.1:0.0)?
>
> The local xterm (the one that anchors the server) is fast.
>
>  Remote Konsole - super slow
>  Remote Gedit - slow
>  Remote Xterm - fast!
>
> At a guess, are some programs pushing pixels across the wire, to
> assemble text, while some programs use the local fonts?

It looks like you and Larry kinda got off on the wrong foot there.  Try to 
get beyond that, and look at the help he tried to give you, but you 
ignored...

He already indicated to you that there are no performance switches to turn 
on/off.

He also asked you to follow the proper reporting guidelines, which often 
give other people on the list clues as to what may be wrong in your 
installation and/or configuration.



However, one more suggestion for you...if you go back and read that FAQ 
entry again ...



it says that you may have to disable firewall/VPN/etc. software thay may 
have installed its own TCP/IP stack.  Often, disabling is not enough, you 
have to completely uninstall it.  This isn't based on my own experience, but 
from other comments on this list, so you may want to search the archives 
more for what software often causes these kinds of problems.


Cary




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Re: slow paints despite fast hardware

[Phlip]

Cary Jamison wrote:




it says that you may have to disable firewall/VPN/etc. software thay may
have installed its own TCP/IP stack.  Often, disabling is not enough, you
have to completely uninstall it.  This isn't based on my own experience, but
from other comments on this list, so you may want to search the archives
more for what software often causes these kinds of problems.


That would make everything equally slow. Right now, XTerm is fast and
Gedit & Konsole are slow. (Gnome and KDE, respectively.)

The KDE FAQ also didn't have a good suggestion, so I seem to be stuck
between FAQs here...

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Re: slow paints despite fast hardware

[Peter Farley]

PMFJIH, but is the WinXP screen resolution
*substantially* different from the ubuntu screen
resolution?  I do not know if it solves anything, but
could a big difference in the screen resolutions
explain observably slower paints?

Just a thought.

Peter

--- Phlip <[EMAIL PROTECTED]> wrote:

 
> My Cygwin's X server generates the slowest GUIs on
> my workstation. The
> rest handle simple repaints in user-time. I have
> observed this
> problem, off and on, over several different
> platforms and
> configurations, for over a year by now, and it has
> limited my ability
> to make Cygwin productive. The problem's tenacity
> makes me think it is
> commonly reported and easy to fix. My inability to
> read the various
> xinitrc-related batch files, and to Google for their
> documentation and
> online FAQs, has told me simply that there is
> something that I don't
> know how to even ask about.
> 
> So I ask my question as a metaphor. Because I have
> experience with GUI
> systems that ship in a safe configuration, instead
> of the fast
> configuration, I ask if this is the case for
> Cygwin's X server.
> 
> Things go downhill from there, but I'm not sure if
> any better metaphor
> were possible...
> 
> The question remains: Where do I start the
> investigate, and what RC
> files and setting lines might control the situation?
> 
> -- 
>   Phlip


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http://mail.yahoo.com 

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Re: slow paints despite fast hardware

[Phlip]

Peter Farley wrote:


PMFJIH, but is the WinXP screen resolution
*substantially* different from the ubuntu screen
resolution?  I do not know if it solves anything, but
could a big difference in the screen resolutions
explain observably slower paints?


Rootless?

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Re: slow paints despite fast hardware

[Phlip]

Peter Farley wrote:


PMFJIH


Here are animations of the effect:

http://www.zeroplayer.com/fastXterm.avi
http://www.zeroplayer.com/slowKde.avi

Download those; don't just click on them.

Gnome is slow too, but I'm open to the suggestion that KDE and Gnome
have similar bugs that should be pursued separately. (On /their/
mailing lists!;)

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Re: slow paints despite fast hardware

[Phlip]

Here are animations of the effect:

http://www.zeroplayer.com/fastXterm.avi
http://www.zeroplayer.com/slowKde.avi


Just to finish the thread, turning compression on seems to have helped.

 ssh -X -C [EMAIL PROTECTED]

I did not report that earlier because at first it did not work. The
above animations were collected after turning it on. I guess it took a
while to take effect!

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Re: slow paints despite fast hardware

[Phlip]

Phlip wrote:


> Here are animations of the effect:
>
> http://www.zeroplayer.com/fastXterm.avi
> http://www.zeroplayer.com/slowKde.avi

Just to finish the thread, turning compression on seems to have helped.

 ssh -X -C [EMAIL PROTECTED]

I did not report that earlier because at first it did not work. The
above animations were collected after turning it on. I guess it took a
while to take effect!


If I start X first (startx), then in another CygWin I ssh to the
target machine, the system is slow.

If I ssh to the target machine first, then startx, the system is fast.

So this irritation is sufficiently worked-around, yet there's still
something going on in there!


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