tree 2666f7bcd3b6658319acce59caa7f26060477525
parent 28323391c40f53f08cbd23c8854df8cc5c3c9e21
author Nigel Tao <nigeltao@golang.org> 1356138553 +1100
committer Nigel Tao <nigeltao@golang.org> 1356138553 +1100
golang-hg 3d9483b02eb36eab1eb8395dea3675b8e3e3dec8

go.net/publicsuffix: tighten the encoding from 8 bytes per node to 4.

On the full list (running gen.go with -subset=false):

Before, there were 6086 nodes (at 8 bytes per node) before. After,
there were 6086 nodes (at 4 bytes per node) plus 354 children entries
(at 4 bytes per node). The difference is 22928 bytes.

In comparison, the (crushed) text is 21082 bytes, and for the curious,
the longest label is 36 bytes: "xn--correios-e-telecomunicaes-ghc29a".

All 32 bits in the nodes table are used, but there's wiggle room to
accomodate future changes to effective_tld_names.dat:

The largest children index is 353 (in 9 bits, so max is 511).
The largest node type is 2 (in 2 bits, so max is 3).
The largest text offset is 21080 (in 15 bits, so max is 32767).
The largest text length is 36 (in 6 bits, so max is 63).

benchmark                old ns/op    new ns/op    delta
BenchmarkPublicSuffix        19948        19744   -1.02%

R=dr.volker.dobler
CC=golang-dev
https://golang.org/cl/6999045