forked from Imagelibrary/littlefs
e780fd40f7
Inspired heavily by d3 and brendangregg's flamegraphs, codemapd3.py is
intended to be a powerful high-level code exploring tool.
It's a visual tool, so probably best explained visually:
$ CFLAGS='-DLFS_NO_LOG -DLFS_NO_ASSERT' make -j
$ ./scripts/codemapd3.py \
lfs.o lfs_util.o \
lfs.ci lfs_util.ci \
-otest.svg -W1500 -H700 --dark
updated test.svg, code 35528 stack 2440 ctx 636
And open test.svg in a browser of your choice.
(TODO add a make rule for this)
---
Features include:
- Rendering of code cost in a treemap organized by subsystem (based on
underscore-separated namespaces), making it relatively easy to see
where the bulk of our code cost comes from.
- Rendering of the deepest stack/ctx cost as a set of tiles, making it
relatively easy to see where the bulk of our stack cost comes from.
- Interactive (on mouseover) rendering of callgraph info, showing
dependencies and relevant stack/ctx costs per-function.
This currently includes 4 modes:
1. mode-callgraph - This shows the full callgraph, including all
children's children, which is effectively all dependencies of that
function, i.e. the total code cost necessary for that _specific_
function to work.
2. mode-deepest - This shows the deepest/hot path of calls from that
function, which is every child that contributes to the function's
stack cost.
3. mode-callees - This shows all functions the current function
immediately calls.
4. mode-callers - This shows all functions that call the current
function.
And yes, cycles are handled correctly: We show the deepest
non-cyclical path, but display the measured stack usage as infinite.
For more details see ./scripts/codemapd3.py --help.
---
One particularly neat feature I'm happy about is -t/--tiny, which scales
the resulting image such that 1 pixel ~= 1 byte. This should be useful
for comparing littlefs to other filesystems in a way that is visually
interesting.
- d3 - https://d3js.org
- brendangregg's flamegraphs - https://github.com/brendangregg/FlameGraph