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diff --git a/chromium/docs/website/site/chromium-os/how-tos-and-troubleshooting/a-brief-perf-how-to/index.md b/chromium/docs/website/site/chromium-os/how-tos-and-troubleshooting/a-brief-perf-how-to/index.md deleted file mode 100644 index e89fb9c339f..00000000000 --- a/chromium/docs/website/site/chromium-os/how-tos-and-troubleshooting/a-brief-perf-how-to/index.md +++ /dev/null @@ -1,121 +0,0 @@ ---- -breadcrumbs: -- - /chromium-os - - Chromium OS -- - /chromium-os/how-tos-and-troubleshooting - - How Tos and Troubleshooting -page_name: a-brief-perf-how-to -title: Timechart how-to ---- - -Developer builds contain a performance analysis command called `perf` that can -be used to create an SVG output file similar to `bootchart`; the chart shows how -CPU cycles and I/O wait times are distributed across processes in the system -over time. - -Below is a short primer in four lessons describing how to generate and view -output from `perf timechart`. - -## Lesson 1 - a simple example - -1. Boot Chromium OS, and open a terminal. -2. Run this command: - - ```none - sudo perf timechart record - ``` - -3. Run your workload. A workload isn't necessary if all you want to see - is a chart of an idle system. :-) -4. When your workload is done, interrupt the process started in step 2 - using ^C, or kill -2. - -**Explanation**: Without arguments, `perf timechart record` runs forever -gathering data, until stopped by SIGINT. Note that only SIGINT works; SIGTERM -will kill the process without producing the necessary output. When the command -completes, you'll see two new files: `perf.data` and `trace.out.` - -## Lesson 2 - how to generate and view the chart - -1. In the directory where you ran Lesson 1, run this command: - - ```none - sudo perf timechart - ``` - -2. The output image will be stored in a file named `output.svg`. Use - `scp` or some equivalent to copy the file to another system for - viewing. - -**Tips for viewing**: Some browsers may have trouble displaying the image. The -author of timechart recommends the Inkscape image editor: - -<http://www.inkscape.org/> - -Inkscape does a good job of displaying the fine details, but it may be a bit -slow for the large timechart images. You should exercise patience when opening, -magnifying, or scroling images. - -## Lesson 3 - how to avoid using SIGINT - -1. Run this command: - - ```none - sudo perf timechart record sleep 5 - ``` - -2. Run a workload that will finish within 5 seconds; for longer - workloads, use a more appropriate sleep time in step 1. -3. Generate and view the output as described in Lesson 2. - -**Explanation**: If there are arguments to `perf timechart record`, the -arguments are treated as a command to run as a subprocess of `perf. perf` -gathers data until the process terminates. - -If your workload is triggered by a single command, that command can be used in -place of 'sleep 5'. Note that if the workload acts as a daemon (that is, forks a -child and exits), `perf` will terminate with the parent terminates; this likely -isn't what you'd want. - -## Lesson 4 - how to get a timechart of system boot - -1. Install bootchart on your workstation. For ubuntu: - - ```none - sudo apt-get install bootchart - ``` - -2. emerge and install bootchart onto your DUT: - - ```none - emerge-$BOARD bootchart && cros deploy $DUT bootchart - ``` - -3. reboot DUT - - ```none - ssh $DUT reboot - ``` - -4. bootchart will log events in - `/var/log/bootchart/boot-<timestamp>.tgz`. It will collect data - until the DUT upstart sequence has fully completed. Retrieve the - archive(s) with - - ```none - scp $DUT:/var/log/bootchart/boot-<timestamp>.tgz /tmp - ``` - -5. generate SVG graphics - - ```none - F=boot-<timestamp> ; bootchart --format=svg -o $F.svg $F.tgz - ``` - - or in a loop with - - ```none - scp $DUT:/var/log/bootchart/boot-*.tgz . && for i in *; do F=${i%.tgz}; bootchart --format=svg -o "${F}.svg" "${F}.tgz"; done - ``` - - The svg file(s) are ready for viewing.
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