Month: January 2018

Software Development

Memory and Mining in Ethereum – a look in Geth internals

Posted on by alanbuxton

There are a few comments on my guide to getting started with Ethereum private networks about mining taking ages to run, or apparently not running at all. The consensus seems to be that you need to be on a 64 bit OS and using plenty of memory. In this post I’ll compare mining in a private network with 1Gb, 2Gb and 4Gb virtual machine configurations. This was an academic exercise I went through for my own interest, but hopefully will be of some interest to people who enjoy understanding a bit more about how the code works.

Here are the steps, collected from various docs, that I went through on Ubuntu. The developer’s guide was my starting point.

Install Go:

sudo add-apt-repository ppa:gophers/archive
sudo apt-get update
sudo apt-get install golang-1.9

Set GOPATH:

mkdir -p ~/go; echo "export GOPATH=$HOME/go" >> ~/.bashrc
echo "export PATH=$PATH:$HOME/go/bin:/usr/local/go/bin" >> ~/.bashrc
source ~/.bashrc

A few more commands so Go can be found in the GOPATH

mkdir $GOPATH/bin
sudo ln -s /usr/lib/go-1.9/bin/go $GOPATH/bin/go

Clone geth repo and build geth:

git clone git@github.com:ethereum/go-ethereum.git $GOPATH/src/github.com/ethereum/go-ethereum
cd $GOPATH/src/github.com/ethereum/go-ethereum
go install -v ./cmd/geth

You’ve probably got two geths installed now, a system-wide one and the one that you just installed, as below.

ethuser@eth-host:~$ geth version | grep '^Version:'
Version: 1.7.3-stable
ethuser@eth-host:~$ $GOPATH/bin/geth version | grep '^Version:'
Version: 1.8.0-unstable

Before we do anything else, let’s just double check that you can run the newly installed geth. Assuming you used the guide in the previous post:

cd ~
$GOPATH/bin/geth --datadir node1 --networkid 98765 console

Add some logging to geth. See this commit which provides additional logging during the mining process:

https://github.com/alanbuxton/go-ethereum/commit/3990f15fab13d32f9b9f0224367295f285f7f9db#diff-d48da17e6237684b832b97db3107179f

Apply these changes to your local version, or if you prefer you can clone the branch in my fork that has these changes already in.

git clone -b extra_logging --depth 1 https://github.com/alanbuxton/go-ethereum.git $GOPATH/src/github.com/ethereum/go-ethereum

Rebuild your local version using go install -v ./cmd/geth and now you’ll get some more logging when you mine in your private network. See below for some examples with extra logging with 4Gb, 2Gb and 1Gb virtual machine configurations:

4Gb

> miner.start(1);admin.sleepBlocks(1);miner.stop()
INFO [01-26|09:37:47] Updated mining threads threads=1
INFO [01-26|09:37:47] Transaction pool price threshold updated price=18000000000
INFO [01-26|09:37:47] Starting mining operation 
INFO [01-26|09:37:47] Commit new mining work number=34 txs=0 uncles=0 elapsed=125.978µs
INFO [01-26|09:37:47] Started ethash search for new nonces miner=0 seed=7377726478179259701
INFO [01-26|09:38:05] Still mining miner=0 attempts=1000 duration=18s
INFO [01-26|09:38:06] Still mining miner=0 attempts=2000 duration=19s
INFO [01-26|09:38:06] Still mining miner=0 attempts=4000 duration=19s
INFO [01-26|09:38:06] Still mining miner=0 attempts=8000 duration=19s
INFO [01-26|09:38:07] Still mining miner=0 attempts=16000 duration=20s
INFO [01-26|09:38:08] Still mining miner=0 attempts=32000 duration=21s
INFO [01-26|09:38:09] Finished mining miner=0 attempts=42332 duration=22s
INFO [01-26|09:38:09] Successfully sealed new block number=34 hash=c53c2f…45286c
INFO [01-26|09:38:09] 🔨 mined potential block number=34 hash=c53c2f…45286c

2 Gb

> miner.start(1);admin.sleepBlocks(1);miner.stop()
INFO [01-26|10:32:19] Updated mining threads threads=1
INFO [01-26|10:32:19] Transaction pool price threshold updated price=18000000000
INFO [01-26|10:32:19] Starting mining operation 
INFO [01-26|10:32:19] Commit new mining work number=37 txs=0 uncles=0 elapsed=129.734µs
INFO [01-26|10:32:19] Started ethash search for new nonces miner=0 seed=4187772785547710899
INFO [01-26|10:32:40] Still mining miner=0 attempts=1000 duration=21s
INFO [01-26|10:32:46] Still mining miner=0 attempts=2000 duration=27s
INFO [01-26|10:32:49] Still mining miner=0 attempts=4000 duration=30s
INFO [01-26|10:32:49] Still mining miner=0 attempts=8000 duration=30s
INFO [01-26|10:32:50] Still mining miner=0 attempts=16000 duration=31s
INFO [01-26|10:32:51] Still mining miner=0 attempts=32000 duration=32s
INFO [01-26|10:32:53] Finished mining miner=0 attempts=57306 duration=34s
INFO [01-26|10:32:53] Successfully sealed new block number=37 hash=068096…c31777
INFO [01-26|10:32:53] 🔨 mined potential block number=37 hash=068096…c31777

1Gb

I cancelled after over half an hour…

> miner.start(1);admin.sleepBlocks(1);miner.stop()
INFO [01-26|09:51:58] Updated mining threads threads=1
INFO [01-26|09:51:58] Transaction pool price threshold updated price=18000000000
INFO [01-26|09:51:58] Starting mining operation 
INFO [01-26|09:51:58] Commit new mining work number=37 txs=0 uncles=0 elapsed=243.956µs
INFO [01-26|09:51:58] Started ethash search for new nonces miner=0 seed=1420748052411692923
INFO [01-26|09:53:11] Still mining miner=0 attempts=1000 duration=1m13s
INFO [01-26|09:54:23] Still mining miner=0 attempts=2000 duration=2m25s
INFO [01-26|09:56:52] Still mining miner=0 attempts=4000 duration=4m54s
INFO [01-26|10:01:53] Still mining miner=0 attempts=8000 duration=9m55s
INFO [01-26|10:11:49] Still mining miner=0 attempts=16000 duration=19m51s
INFO [01-26|10:30:27] Still mining miner=0 attempts=32000 duration=38m29s
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