On Mar 16, 8:00 pm, Cyril Novikov <spamt...@[EMAIL PROTECTED]
> wrote:
> That's unlikely. 2300 cycles is about 1us, no memory is that slow. That
> looks more like ISA bus access time. Do you have any I/O instructions or
> MMIO accesses there, by any chance? How do you measure cycles, did you
> remember to use synchronizing instructions with RDTSC?
Actually, PCI reads tend to take about 1us, and they are generally
implemented as memory reads.
Are you reading an interrupt status register to check for the
interrupt condition, and that's the memory read that eats a us?
What is this memory location?
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