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X-Bullshit: non-blocking pipelining-aware STM scripting software 
Subject: Re: [9front] Speeding up snoopy(8)
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Quoth David Arroyo <droyo@aqwari.net>:
> I will experiment with putting the pwrite in a separate thread, and
> look for small performance improvements in the other functions. I
> am not sure why nsec() time is so high, but I think that's a function
> that could perform very differently on real vs virtual hardware, so
> I'm hesitant to try to improve it until I get 9front running on a
> real machine.

nsec() is a function that results in a syscall.  It is also affected
by time adjustments, to my knowledge.  At some point I replaced nsec()
call with a (somewhat dirty) nanosec() in vmx, see
/sys/src/cmd/vmx/nanosec.c

It would be nice to have a way to get monotonic timestamps in userspace
without having to go into the kernel. For now, you can try nanosec and
see if anything changes.