Re: 1.0-9526 occasional few second freeze with freeciv
I used this weekend to do some systematic test on the system.
The problem was reproduced (or probed) using only freeciv, typically with multiple windows open (game + city windows).
First test was with NvAGP 1 (nVidia AGP backend, so intel_agp module not loaded). AGP was set to 2x (from default 4x) in BIOS, confirmed in /proc/driver/nvidia/agp/status.
This test case showed the problem. Freezes and Xvid errors.
Second test, as above, but with USWC (Uncacheable Speculative Write Combining) disabled (UC only). Problem still occurring.
Third test, as above, but with AGP aperture reduced from 64MB to 32MB. Problem still occurring, maybe even more often.
Fourth test, with all enabled, but with NvAGP 0, which should be no AGP at all (if I understood it correctly). Problem still occurring. Note that I was wrong when I wrote that this setting was not showing the issue, actually freeciv was causing the freeze and Xvid as usual.
Fifth test, with all enabled, but with the "nv" driver. No problem at all. Even if I must say that, maybe, some black flashing might have occurred, eventually like video refresh not VSync'ed. In any case no freezing and not real sync loss. At least not clearly visible.
Now, from all this I can see that AGP 2x or 4x makes no difference, but also no AGP at all makes no difference, while the "nv" showed no issue, thus leading to the suspect that something in the driver might be the cause.
I have another note. It seems to me that this issue popped up after Xorg 7.0 (or 7.1), so it might be related to the driver-server interaction.
I also saw, here and there in the forum, problems which could look similar to this one, but maybe showing up differently.
Is there anything else that could be tested in order to narrow down this issue?
For freeciv is not much of a problem, but since it occurs while browsing, it becomes pretty pretty annoying.