These are some very basic and unscientific benchmarks of various commands
provided by `xsv`. Please see below for more information.
These benchmarks were run with
[worldcitiespop_mil.csv](http://burntsushi.net/stuff/worldcitiespop_mil.csv),
which is a random 1,000,000 row subset of the world city population dataset
from the [Data Science Toolkit](https://github.com/petewarden/dstkdata).
These benchmarks were run on an Intel i3930K (6 CPUs, 12 threads) with 32GB of
memory.
```
count 0.54 seconds 84.28 MB/sec
flatten 4.26 seconds 10.68 MB/sec
flatten_condensed 4.40 seconds 10.34 MB/sec
frequency 3.50 seconds 13.00 MB/sec
index 0.52 seconds 87.52 MB/sec
sample_10 0.74 seconds 61.50 MB/sec
sample_1000 0.71 seconds 64.10 MB/sec
sample_100000 0.87 seconds 52.31 MB/sec
search 1.11 seconds 41.00 MB/sec
select 0.70 seconds 65.01 MB/sec
sort 3.79 seconds 12.00 MB/sec
slice_one_middle 0.34 seconds 133.86 MB/sec
slice_one_middle_index 0.01 seconds 4551.36 MB/sec
stats 1.56 seconds 29.17 MB/sec
stats_index 0.29 seconds 156.94 MB/sec
stats_everything 4.84 seconds 9.40 MB/sec
stats_everything_index 3.58 seconds 12.71 MB/sec
```
### Details
The purpose of these benchmarks is to provide a rough ballpark estimate of how
fast each command is. My hope is that they can also catch significant
performance regressions.
The `count` command can be viewed as a sort of baseline of the fastest possible
command that parses every record in CSV data.
The benchmarks that end with `_index` are run with indexing enabled.