README
¶
Introduction
The coffee program is a tool for studying parallelism, contention,
utilization, latency, and throughput. It simulates making coffee with
a set of machines (grinder for beans, espresso maker, steamer for
milk) and measures the performance of various implementations. The
measurements show the effects of various structural changes and
optimizations.
Run coffee with no arguments to simulate the "ideal" scenario with 1
worker. Run coffee --help to see flags for configuring the
simulation. See generate.sh for commands that generate measurements
for many different scenarios.
Notes
Run generate.sh to regenerate *.csv files.
Use taskset -c 0-5 go run *.go to restrict execution to specified CPU IDs.
Use https://github.com/aclements/perflock to prevent multiple benchmarks from running at once and keep CPU from running too hot (and so triggering CPU throttling).
Generate torch graphs
foreach mode ( \
ideal locking finelocking parsteam americano espresso \
multi-1 multi-2 multi-4 multi-8 \
linearpipe-0 linearpipe-1 linearpipe-10 \
splitpipe-0 splitpipe-1 splitpipe-10 \
multipipe-1 multipipe-2 multipipe-4 multipipe-8 \
)
taskset -c 0-5 go run *.go --dur=3s --par=0 --trace=./trace-$mode.out -mode=$mode
go tool trace --pprof=sync ./trace-$mode.out > ./sync-$mode.pprof
go-torch -b ./sync-$mode.pprof -f ./torch-$mode.svg
end
Documentation
¶
Overview ¶
The coffee command simulates a small parallel pipeline and outputs CSV.
The pipeline consists of three stages: grinding coffee beans, preparing espresso, and steaming milk. Each stage contends on the respective machine (grinder, espresso machine, steamer).
This simulation reports throughput, latency, and utilization. It can also create an execution trace with the --trace flag.
Source Files