LuaJit 2.1 beta 3 vs Rust 1.34.1 https://habr.com/ru/post/450512/

test.lua

local json = require('rapidjson')

local path = "C:/temp/1.json"

local file = io.open(path, 'r')

local debtors, debtorsMap, company, phones, phone, debt, debtor

debtors = {}

debtorsMap = {}

local s = file:read(256*1024)

local v, h

local b, e

function find_object(init)
    local x = 0
    local b = s:find("{", init, true)
    if b then
        local str, esc = false, false
        for i = b, #s do  
            local c = s:byte(i)
            if esc then
                esc = false    
            elseif str then
                if c == 0x5C then -- \
                    esc = true
                elseif c == 0x22 then
                    str = false
                end
            elseif c == 0x22 then -- "
                str = true
            elseif c == 0x7B then -- {
                x = x + 1
            elseif c == 0x7D then -- }
                x = x - 1
                if x == 0 then
                    return b, i
                end
            end
        end
    end
    return b, nil
end

while s do
    
    if h then
        s = h..s
    end

    b, e = find_object(1)

    while e do

        v = json.decode(s:sub(b, e))
        
        company = v.company

        if type(company) == 'table' then
            company = company.name
        end

        assert(company)

        phones = v.phones or {}

        if type(phones) ~= 'table' then
            phones = {phones}
        end

        phones[#phones+1] = v.phone

        debt = v.debt or 0

        for _, phone in ipairs(phones) do
            debtor = debtorsMap[phone]
            if debtor ~= nil then
                break
            end
        end

        if debtor == nil then
            debtor = {
                companies = {},
                phones = {},
                debt = 0
            }
            debtors[#debtors+1] = debtor
        end

        debtor.companies[company] = true
        debtor.debt = debtor.debt + debt
        for _, phone in ipairs(phones) do
            debtor.phones[phone] = true
            debtorsMap[phone] = debtor    
        end
        
        b, e = find_object(e)   

    end

    h = b and s:sub(b)

    s = file:read(256*1024)

end

function out_list(src)
    local t = {}
    for k in pairs(src) do
        t[#t+1] = k
    end
    return table.concat(t, ", ")
end

print("--------------------------")
for _, d in ipairs(debtors) do
    print("debt: "..d.debt)
    print("companies: "..out_list(d.companies))
    print("phones:"..out_list(d.phones))
    print("--------------------------")
end 

print('done', os.clock(), 'sec.')

--[[
.\luajit.exe -v
LuaJIT 2.1.0-beta3 -- Copyright (C) 2005-2017 Mike Pall. http://luajit.org/
.\luajit.exe .\test.lua
--------------------------
debt: 910000000
companies: Шестерочка, Рога и копыта, Первая коллекторская
phones:788, 456, 789, 2128506, 123, 234
--------------------------
debt: 433200000
companies: Святой престол, Казачий спас
phones:234567, 666, 345678
--------------------------
done    1.353   sec.
--]]

Новая версия на Rust: https://gist.github.com/red75prime/53111e066cb1a32721c461b24eadbe6e

.\rustjson.exe -f "C:\temp\1.json"
1.2950531s