[systemd-devel] [PATCH] bootchart: use conf-parser & CamelCase names in .conf

Kok, Auke-jan H auke-jan.h.kok at intel.com
Wed Feb 13 16:37:42 PST 2013

On Wed, Feb 13, 2013 at 4:00 PM, Kay Sievers <kay at vrfy.org> wrote:
> On Thu, Feb 14, 2013 at 12:42 AM, Kok, Auke-jan H
> <auke-jan.h.kok at intel.com> wrote:
>> On Wed, Feb 13, 2013 at 3:32 PM, Lennart Poettering
>> <lennart at poettering.net> wrote:
>>> On Wed, 13.02.13 14:27, Kok, Auke-jan H (auke-jan.h.kok at intel.com) wrote:
>>>> > Hmm, what does this stand for? Wikipedia doesn't have it, can't be that
>>>> > well known...
>>>> PSS is the alternative to RSS... You probably won't find an
>>>> explanation anywhere else but the kernel source code:
>>>> Documentation/filesystems/proc.txt:
>>>> =====
>>>> The /proc/PID/smaps is an extension based on maps, showing the memory
>>>> consumption for each of the process's mappings. For each of mappings there
>>>> is a series of lines such as the following:
>>>> 08048000-080bc000 r-xp 00000000 03:02 13130      /bin/bash
>>>> Size:               1084 kB
>>>> Rss:                 892 kB
>>>> Pss:                 374 kB
>>>> [...]
>>>> The first of these lines shows the same information as is displayed for the
>>>> mapping in /proc/PID/maps.  The remaining lines show the size of the mapping
>>>> (size), the amount of the mapping that is currently resident in RAM (RSS), the
>>>> process' proportional share of this mapping (PSS),
>>>> =====
>>>> so, PSS translates to "proportional share of the mapping(size) that is
>>>> resident in RAM"
>>>> PSS will do fine, I suppose :^)
>>> RSS is an acronym for "Residential Set Size". PSS for
>>> "Propertional Set Size". Hence the option for bootchart should be
>>> "ProportionalSetSize="?
>>> What does the option actually do? Do we actually need the option? If
>>> not, we might just drop this source of confusion? And we do need it,
>>> maybe make it explanatory as int "PlotProportionalSetSize=" or so?
>> When enabled, it creates an additional graph (just like the entropy
>> option, or, if you have booted with initcall_debug) that plots the PSS
>> for each process.
>> It's a highly usable graph for people working on systems with less
>> memory, so, I'd like to keep it.
>> Example of how it looks here:
>>     http://foo-projects.org/~sofar/bootchart-20120401-0710.svg
>> Plotting of PSS is disabled by default since it has quite a
>> performance impact (it requires parsing /proc/<NN>/smaps for each
>> process, which can be hundreds of kilobytes large each).
> That looks nice, yeah.
> But shouldn't it just be called PlotMemoryUsage= or something instead
> of the using the "algorithm name" in the config switch to enable it?

Right, that's totally fine with me, really. I suck at naming things ;^)

EntropyGraph... similarly thus.


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