Add a note about CPU Scaling and benchmarks.
@@ -32,6 +32,7 @@ benchmark runs, or calculate p-values when comparing numbers before and after a
code change. To install it, first install Go, then run `go get
golang.org/x/perf/cmd/benchstat`.
+
## puffs bench
As mentioned above, individual benchmark programs can be run manually. However,
@@ -52,6 +53,19 @@ or
puffs bench -ccompilers=gcc -reps=3 -focus=Benchmarkpuffs_gif_lzw std/gif
+## CPU Scaling
+
+CPU power management can inject noise in benchmark times. On a Linux system,
+power management can be controlled with:
+
+ # Query.
+ cpupower --cpu all frequency-info --policy
+ # Turn on.
+ sudo cpupower frequency-set --governor powersave
+ # Turn off.
+ sudo cpupower frequency-set --governor performance
+
+
# GIF
The 1k, 10k, etc. numbers are approximately how many bytes of pixel data there
