Scrolling in 6.8.1 much slower than 6.7.0

[Rob]

Second try, didn't realise this list was subscription only. But while getting
my message rejected, I discovered that turning ShadowFB on brought scrolling
back to 6.7.0 speeds. I'd rather not use ShadowFB though, since it's slower
and uses more memory (right?)

----- Original message -----

Hi all,

I've just built 6.8.1 on my old laptop, and I notice that scrolling windows
is a lot slower in the new version. It's most obvious in abiword, but I see
it in Firefox and other programs as well. With 6.8.1 I can see the window
being redrawn from bottom to top or vice versa, as if it's not accelerated.
To really see the difference, use abiword 2.0.x and turn smooth scrolling
on - with 6.7.0 on this hardware it's a bit uncomfortable, but with 6.8.1
it's truly glacial.

Relevant specs:

300MHz mobile P-II
2MB PCI Neomagic nm2160 (using neomagic driver, running at 1024x768x16bpp)
192MB RAM
Linux kernel 2.6.9-mm1
GCC 3.4.3
External Freetype 2.1.9 and Fontconfig 2.2.96

I rebuilt 6.7.0 to check after I noticed this, so the compiler etc. is the
same. I'm not using the composite extension, and MTRRs look like they're set
up properly in both cases. I'm using the same xorg.conf for both (except for
the keyboard driver change).

Is this a known issue, or is there something I can try to narrow this down?

Also, with 6.8.1 I get a few errors like
"No matching visual for __GLcontextMode with visual class = 3 (32772), nplanes = 16"
on startup. Are these harmless or not, and where are they coming from?

TIA

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