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Re: Some newbie questions


On 08/17/2016 09:06 PM, David Smith wrote:
On 08/17/2016 10:15 AM, Avi Kivity wrote:

... stuff deleted ...

My load indeed calls epoll_wait() at a high rate, with zero timeout.
But now it's completely dominated by tracing overhead.
I'm not sure how much it will help, but one easy fix would be to replace
all your '[pid(), tid()]' array indexing with just '[tid()]' array indexing.

Try changing that and see if the tracing overhead goes down a bit.


Yeah, I forgot to do that.


But it's really unlikely to help, all the overhead is coming from syscall tracing, which I didn't ask for.


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