[performance] makes build 1.5 times slower

[stanf0rd]

Problem:

Enabling filesize plugin makes build 1.5 times slower

Filesize enabled:

Filesize disabled:

Versions:

MacOS 11.3.1
Node 14 LTS
Rollup v2.47.0
rollup-plugin-filesize v1.5.1

I could provide more additional info about my config, if you'll need

[stanf0rd]

it was obvious, but the reason is minifying and gzipping are needed to calculate minified and gzipped sizes :)
And these operations are expensive.

I think, it would be great to put a disclaimer to the Readme about it.

[Haroenv]

If you disable just the minifying it's significantly faster, gzip isn't really slow