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[docs] Change llvm-xray options to use the preferred double-dash forms

This commit is contained in:
Fangrui Song 2021-08-15 21:09:35 -07:00
parent ca637014f1
commit 676f16bed5
1 changed files with 14 additions and 14 deletions
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28
llvm/docs/XRayExample.rst
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@ -78,7 +78,7 @@ been instrumented. We can see an example accounting with ``llvm-xray account``:
::
$ llvm-xray account xray-log.llc.m35qPB -top=10 -sort=sum -sortorder=dsc -instr_map ./bin/llc
$ llvm-xray account xray-log.llc.m35qPB --top=10 --sort=sum --sortorder=dsc --instr_map=./bin/llc
Functions with latencies: 29
funcid count [ min, med, 90p, 99p, max] sum function
187 360 [ 0.000000, 0.000001, 0.000014, 0.000032, 0.000075] 0.001596 LLLexer.cpp:446:0: llvm::LLLexer::LexIdentifier()
@ -103,7 +103,7 @@ output for an example trace would look like the following:
::
$ llvm-xray convert -f yaml -symbolize -instr_map=./bin/llc xray-log.llc.m35qPB
$ llvm-xray convert -f yaml --symbolize --instr_map=./bin/llc xray-log.llc.m35qPB
---
header:
version: 1
@ -151,7 +151,7 @@ function bodies to 1. We can do that with the
$ XRAY_OPTIONS="patch_premain=true" ./bin/llc input.ll
==69819==XRay: Log file in 'xray-log.llc.5rqxkU'
$ llvm-xray account xray-log.llc.5rqxkU -top=10 -sort=sum -sortorder=dsc -instr_map ./bin/llc
$ llvm-xray account xray-log.llc.5rqxkU --top=10 --sort=sum --sortorder=dsc --instr_map=./bin/llc
Functions with latencies: 36652
funcid count [ min, med, 90p, 99p, max] sum function
75 1 [ 0.672368, 0.672368, 0.672368, 0.672368, 0.672368] 0.672368 llc.cpp:271:0: main
@ -205,7 +205,7 @@ The way to use the command is to output the top stacks by call count and time sp
::
$ llvm-xray stack xray-log.llc.5rqxkU -instr_map ./bin/llc
$ llvm-xray stack xray-log.llc.5rqxkU --instr_map=./bin/llc
Unique Stacks: 3069
Top 10 Stacks by leaf sum:
@ -227,9 +227,9 @@ In the default mode, identical stacks on different threads are independently
aggregated. In a multithreaded program, you may end up having identical call
stacks fill your list of top calls.
To address this, you may specify the ``-aggregate-threads`` or
``-per-thread-stacks`` flags. ``-per-thread-stacks`` treats the thread id as an
implicit root in each call stack tree, while ``-aggregate-threads`` combines
To address this, you may specify the ``--aggregate-threads`` or
``--per-thread-stacks`` flags. ``--per-thread-stacks`` treats the thread id as an
implicit root in each call stack tree, while ``--aggregate-threads`` combines
identical stacks from all threads.
Flame Graph Generation
@ -243,16 +243,16 @@ FlameGraph tool, currently available on `github
To generate output for a flamegraph, a few more options are necessary.
- ``-all-stacks`` - Emits all of the stacks.
- ``-stack-format`` - Choose the flamegraph output format 'flame'.
- ``-aggregation-type`` - Choose the metric to graph.
- ``--all-stacks`` - Emits all of the stacks.
- ``--stack-format`` - Choose the flamegraph output format 'flame'.
- ``--aggregation-type`` - Choose the metric to graph.
You may pipe the command output directly to the flamegraph tool to obtain an
svg file.
::
$llvm-xray stack xray-log.llc.5rqxkU -instr_map ./bin/llc -stack-format=flame -aggregation-type=time -all-stacks | \
$ llvm-xray stack xray-log.llc.5rqxkU --instr_map=./bin/llc --stack-format=flame --aggregation-type=time --all-stacks | \
/path/to/FlameGraph/flamegraph.pl > flamegraph.svg
If you open the svg in a browser, mouse events allow exploring the call stacks.
@ -265,8 +265,8 @@ from the same generated trace:
::
$ llvm-xray convert -symbolize -instr_map=./bin/llc \
-output-format=trace_event xray-log.llc.5rqxkU \
$ llvm-xray convert --symbolize --instr_map=./bin/llc \
--output-format=trace_event xray-log.llc.5rqxkU \
| gzip > llc-trace.txt.gz
From a Chrome browser, navigating to ``chrome:///tracing`` allows us to load
@ -329,7 +329,7 @@ applications:
::
$ llvm-xray graph xray-log.sample.* -m sample -color-edges=sum -edge-label=sum \
$ llvm-xray graph xray-log.sample.* -m sample --color-edges=sum --edge-label=sum \
| unflatten -f -l10 | dot -Tsvg -o sample.svg