[Ethereum] Ganache Processing becomes very slow (with Automining Option) after consecutive thousands transactions

This is what my working dir looks like:

PS C:\Projects\Eth_Dev\simple> ls


    Directory: C:\Projects\Eth_Dev\simple


Mode                LastWriteTime         Length Name
----                -------------         ------ ----
d-----       27/02/2019     21:25                contracts
d-----       27/02/2019     21:22                node_modules
d-----       27/02/2019     21:25                test
-a----       27/02/2019     21:25            691 compile.js
-a----       27/02/2019     21:29            907 deploy.js
-a----       27/02/2019     21:22         152654 package-lock.json
-a----       27/02/2019     21:28            339 package.json

The contents of package.json:

{
  "name": "myContract",
  "version": "1.0.0",
  "description": "",
  "main": "index.js",
  "scripts": {
    "test": "mocha"
  },
  "author": "",
  "license": "ISC",
  "dependencies": {
    "ganache-cli": "^6.2.5",
    "mocha": "^5.2.0",
    "solc": "^0.4.25",
    "truffle-hdwallet-provider": "0.0.3",
    "web3": "^1.0.0-beta.35"
  }
}

The only other command I had to run in addition to npm install was npm install --global --production windows-build-tools

The contents of contracts\myContract.sol

pragma solidity ^0.4.17;

contract MyContract {
    string public message;

    function MyContract(string initialMessage) public {
        message = initialMessage;
    }

    function setMessage(string newMessage) public {
        message = newMessage;
    }
}

This is a deploy.js script that seems to work. Running 'node deploy.js' does the deploy to the Rinkeby network

const HDWalletProvider = require('truffle-hdwallet-provider');
const Web3 = require('web3');
const {interface, bytecode} = require('./compile');

const provider = new HDWalletProvider(
  'your twelve word mnemonic',
  'https://rinkeby.infura.io/v3/YOUR_API_KEY'
);

const web3 = new Web3(provider);

const deploy = async () => {
  const accounts = await web3.eth.getAccounts();
  console.log('Attempting to deploy from account', accounts[0]);


  const result = await new web3.eth.Contract(JSON.parse(interface))
    .deploy({data:bytecode, arguments:['This is deployed!']})
    .send({gas:'1000000', from: accounts[0]});

  console.log('Contract deployed to ', result.options.address);
};
deploy();

There is a reference to a compile file. The compile.js looks like this:

const path = require('path');  //builds a path from the current file.
const fs = require('fs');

//Need the solidity compiler
const solc = require('solc');

//__dirname will get the inbox dir path.
//look in the contracts folder and get a path to the Inbox.sol file.
const myContractPath = path.resolve(__dirname,'contracts','myContract.sol');

//Read in the contents of the file. The raw source code.
const source = fs.readFileSync(myContractPath,'utf8');

//console.log(solc.compile(source,1));
//This will export the compiled file. Make it available
//At the moment only interested in the Inbox contract.
module.exports = solc.compile(source,1).contracts[':MyContract'];

And the output:

PS C:\Projects\Eth_Dev\simple> node .\deploy.js
Attempting to deploy from account 0x15ec...B
Contract deployed to  0x5...2DA9269a