[fglrx] Using fglrx causes excessive hardware interrupts and an extremely slow system
Affects | Status | Importance | Assigned to | Milestone | |
---|---|---|---|---|---|
fglrx-installer (Ubuntu) |
Fix Released
|
High
|
Unassigned |
Bug Description
On an up-to-date Hardy install, when I enable the FGLRX driver using the restricted drivers manager and reboot, either X or FGLRX cause an excessive number of hardware interrupts on my system whenever it's the active console:
jb2@loki:~$ vmstat 1
procs -------
r b swpd free buff cache si so bi bo in cs us sy id wa
4 0 0 572108 10032 227532 0 0 155 30 22797 126 95 3 1 1
1 0 0 572100 10032 227532 0 0 0 0 2 81 100 0 0 0
1 0 0 572100 10032 227532 0 0 0 0 24 146 100 0 0 0
1 0 0 572100 10040 227532 0 0 0 16 7 92 100 0 0 0
1 0 0 572100 10040 227532 0 0 0 0 25 145 100 0 0 0
1 0 0 572100 10040 227532 0 0 0 0 55805 247 98 2 0 0
2 0 0 572100 10040 227532 0 0 0 0 152106 90 100 0 0 0
3 0 0 572100 10040 227532 0 0 0 0 147587 122 100 0 0 0
1 0 0 572100 10040 227532 0 0 0 0 151499 176 99 1 0 0
1 0 0 572100 10040 227532 0 0 0 0 152357 25 100 0 0 0
1 0 0 572100 10040 227532 0 0 0 0 152022 81 100 0 0 0
1 0 0 572100 10052 227532 0 0 0 40 152170 107 100 0 0 0
1 0 0 572100 10052 227532 0 0 0 0 80430 199 100 0 0 0
1 0 0 572100 10052 227532 0 0 0 0 1 79 100 0 0 0
1 0 0 572100 10052 227532 0 0 0 0 24 131 100 0 0 0
1 0 0 572100 10052 227532 0 0 0 0 1 77 100 0 0 0
Around second 6, I switched from tty1 to tty7 (X server), and back to tty1 around second 13.
You can see the number of hardware interrupts jump from around 100/s to 150000/s whenever X is on the active console. Performance is also very noticeably degraded. I've compared this against another system with a slightly older, but still respectable 3D card and the "in" field never exceeds 1000. This system.
The VESA driver doesn't experience this problem, but has other significant issues (like the color map gets all messed up when you switch to a text console and back).
I've tried various options (noapic, pci=routeirq, irqpoll and others) without any improvement to the situation and with some the system locks up hard and needs to be hard-reset.
I've also seen the same problem with this exact same system using Gutsy and Envy-installed FGLRX drivers.
Changed in linux-restricted-modules-2.6.24: | |
importance: | Undecided → High |
status: | New → Triaged |
I should add that it appears that the system referenced above is otherwise functional. Top reports the system is constantly 60% busy in "%hi" when X is on the active console. The remainder of the system feels like it's 60% or busier, like it's running a 500mhz Celeron instead of the actual 2.8ghz Celeron D. Compiz works and 3D performance is fair, but not as fast as I'd expect, and definitely slower than the Nvidia TI4400 I have in a similarly equipped machine.