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Re: NetBSD truss(1), coredumper(1) and performance bottlenecks



n54%gmx.com@localhost (Kamil Rytarowski) writes:

>Observations:
>1. We can observe in both examples that there is a performance issue in
>build.sh, as something attempts to call 5000 times read(2) for 1 byte onl=
>y.

That's probably the shell that must read input byte by byte in most cases.


>2. Firefox and Thunderbird and certainly other similar software calls
>excessively gettimeofday() and clock_gettime(). At least around 100k
>times per 1 minute, and the program spends around 30sec (cumulative time
>from all LWPs in a process) in the kernel space prompting for the
>current time.

That's only a symptom. The real question is why it doesn't sleep.


-- 
-- 
                                Michael van Elst
Internet: mlelstv%serpens.de@localhost
                                "A potential Snark may lurk in every tree."


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