Mirrors/coreutils
2
0
Fork 0
mirror of https://github.com/uutils/coreutils synced 2024-12-14 07:12:44 +00:00
Code Issues Projects Releases Packages Wiki Activity

shuf: update BENCHMARKING.md

Browse source 
Signed-off-by: Christian Menges <christian.menges@outlook.com>
This commit is contained in:
Christian Menges 2022-06-17 20:57:04 +02:00
parent 19a43bf1b7
commit 35e97fe88a
No known key found for this signature in database
GPG key ID: 724A9FD92BC79A39
1 changed files with 28 additions and 5 deletions
Show stats Download patch file Download diff file Expand all files Collapse all files

33
src/uu/shuf/BENCHMARKING.md
View file

@ -4,23 +4,46 @@
benchmark: with and without repetition.
When benchmarking changes, make sure to always build with the `--release` flag.
You can compare with another branch by compiling on that branch and than
You can compare with another branch by compiling on that branch and then
renaming the executable from `shuf` to `shuf.old`.
## Generate sample data
Sample input can be generated using `/dev/random`:
```shell
cat /dev/random | base64 | fold | head -n 50000000 > input.txt
```
To avoid distortions from IO, it is recommended to store input data in tmpfs.
## Without repetition
By default, `shuf` samples without repetition. To benchmark only the
randomization and not IO, we can pass the `-i` flag with a range of numbers to
randomly sample from. An example of a command that works well for testing:
By default, `shuf` samples without repetition.
To benchmark only the randomization and not IO, we can pass the `-i` flag with
a range of numbers to randomly sample from. An example of a command that works
well for testing:
```shell
hyperfine --warmup 10 "target/release/shuf -i 0-10000000"
```
To measure the time taken by shuffling an input file, the following command can
be used::
```shell
hyperfine --warmup 10 "target/release/shuf input.txt > /dev/null"
```
It is important to discard the output by redirecting it to `/dev/null`, since
otherwise, a substantial amount of time is added to write the output to the
filesystem.
## With repetition
When repetition is allowed, `shuf` works very differently under the hood, so it
should be benchmarked separately. In this case we have to pass the `-n` flag or
should be benchmarked separately. In this case, we have to pass the `-n` flag or
the command will run forever. An example of a hyperfine command is
```shell