Messages in this thread |  | | | Date | Fri, 10 Jun 2005 23:06:14 +0200 | | From | Andrea Arcangeli <> | | Subject | Re: Attempted summary of "RT patch acceptance" thread |
| |
On Fri, Jun 10, 2005 at 04:45:38PM -0400, Lee Revell wrote: > AFAICT even RTAI would be affected, because X lets userspace drivers > talk directly to the hardware including wedging the PCI bus.
Yes, I made the usb example exactly to show how latency bugs can be longstanding in the kernel too without requiring X or hardware bugs (this usb thing breaks kernel latency for years and yet nobody fixed it simply because it just works fine in practice, I noticed because apparently my PIT or tsc goes out of sync over time, and in turn my system time was going into the future pretty quick with HZ=1000, or I would have never noticed, of course I'm compiling the kernel with HZ=100 on that system to work around it). Those latency issues can showup in random drivers all the time, and this one was of an extreme magnitude in the millisecond range. The smaller the magnitude of the latency impact, the more frequently you should find it in drivers. - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
|  |