QT4 apps slooooow in ssh

[Roberto Ragusa]

Hi,

some exported (ssh -Y) applications are unbelievably slow, as they
seem to "upload bitmaps" (display is progressively drawn from top to bottom
and network traffic is 11.2MB/s, saturated 100Mbit/s).

This happens only with qt4 apps (e.g. kate), no problem with qt3 apps or
gtk apps.

The qt4 apps run on a F16 KDE desktop with effects enabled, and are displayed
on an F13 KDE desktop with effects disabled.

The F16 machine was originally an F14 and in this case (F14 displaying on F13)
the problem was not present.

Maybe qt4 has a different rendering method which involves a lot of bitmap
shuffling (disaster when remote)?

An additional test, on the F16 machine:
- "kate" is normally fast
- "ssh -Y localhost kate" is slooooooooooooooooooow

What is happening here????

-- 
   Roberto Ragusa    mail at robertoragusa.it