* Asias He <asias.hejun@xxxxxxxxx> wrote:
> BTW. The ping latency was caused by the movement of irq injection outside the
> loop. Suppose we have 5 available buffers and only 1 buffer from tap device.
> We will sleep on read without giving the buffer from tap to guest. The
> latency will be huge in this case.
>
> while(virt_queue__available(vq)) {
> ...
> read(tap_fd)
> ...
> }
> trigger_irq()
But ... in one of the mails one of you claimed that even when moving the irq
notification inside the loop (which we all agreed was necessary to avoid
latencies!) the latencies would still occur during stress-tests.
So something is still not understood here and could hit us anytime with any of
the virtio drivers in the future and such bugs are not always so nice to debug
like the latency problem here ...
Thanks,
Ingo
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