The 02.12.23 at 15:27, Greg Freemyer wrote:
~HOW? ~What can the modem do, that the system gets so busy? ~Interrupts? Well... I did a cat /proc/interrupts, and yes, I noticed that one of them (acpi) was increasing rapidly, much faster than the timer or any of them (6 figures, and increasing the count by thousands every time I checked). After switching off the modem, it only had a value of 41.
Interesting...
Today, I checked again: acpi interupts was 0. I power cycle the modem, and I get 5721 interrupts, and remains there. Why so many?
Every character on a rs-232 port generates a interrupt. That is why they are so inefficient.
True... but there is a 16 bytes I/P buffer, so it could be one every 10 or 14 chars, it can be programmed that way.
It sounds to me like either your modem is bad, or your connection is loose.
No, I think it hangs - twice this year - and starts producing way more interrupts than it should, after the line is dropped. During normal use, or downloads, it does not use so much CPU, but the handler is the pppd daemon. On this occasion the handler was "init" itself.
OTOH, if you were using your modem at the time and doing a download, then thousands of interupts / sec. would be normal.
9600 baud = 960 chars/sec. = 960 irqs/sec.
Mm, yes, I didn't think of that. -- Cheers, Carlos Robinson