Re: [PATCH] perf trace: Simplify '--summary' output

From: Pekka Enberg
Date: Tue Nov 12 2013 - 16:38:14 EST


On 11/12/13 11:36 PM, David Ahern wrote:
On 11/12/13, 2:33 PM, Ingo Molnar wrote:
> Summary of events:
>
> dbus-daemon (555), 10 events, 0.0%, 0.000 msec
>
> msec/call
> syscall calls min avg max stddev
> --------------- -------- -------- -------- -------- ------
> sendmsg 2 0.002 0.005 0.008 55.00
> recvmsg 2 0.002 0.003 0.005 44.00
> epoll_wait 1 0.000 0.000 0.000 0.00
In what units is stddev? Percentage? If yes then it might be useful to
output it as %. [and probably to restrict precision to a single digit,
standard deviations are rarely more accurate than 0.1%.]


%. That was dropped in the recent output change.

Sorry about that. Why do we show them in percentages, btw? Standard deviation is usually represented in the same unit as the data to make it readable.

Pekka
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