Building a Deep Learning / Cryptocurrency PC (#3): Mining
Among the buzzwords in the tech world of 2017, two tower above the rest: deep learning and cryptocurrencies. It seems that everyone I know (in tech) wants to learn these things. And guess what — so do I! So much so that I’m building my own computer in order to facilitate that learning.
What follows are my notes-to-self as I build a computer to learn about deep learning and cryptocurrency mining. In the previous installments we discussed assembling the hardware and installing the OS. In this installment I’ll talk about how to set up a cryptocurrency miner and connect to a pool.
To recap, in case you’re just getting started with this series: my goal in purchasing and building my own PC was to have hardware on hand to run machine learning algorithms on, and bring myself up to speed on the exciting advances happening in AI. But in between running training algorithms, my computer (and it’s hungry hungry GPUs) will sit fallow. We can’t have that!
When I’m not running the computer over training data, I want to have it mining. Even if it’s making only a a little profit, it’s still better than nothing.
Cryptocurrencies
Your first instinct when getting into mining might be to try and mine bitcoin. This would almost certainly be a mistake.
Bitcoin today is mined primarly via ASICS hardware, equipment specialized for mining bitcoins and other cryptocurrencies (but mostly bitcoins). Unless your goal in life is to mine bitcoins — and I suppose there’s nothing wrong with that — ASICS hardware is not a good investment. And without ASICS hardware, it’s hard to compete with the other miners.
There are cryptocurrencies especially designed to prevent mining via specialized hardware, called scrypt coins:
One of the biggest differences between scrypt and SHA-256 is that the former relies heavily on computing resources aside from the processing unit itself, particularly memory. Conversely, SHA-256 doesn’t. This makes it difficult for scrypt-based systems to scale up and use lots of computing power, because they would have to use a proportional amount of memory, and that is expensive. — Danny Bradbury, Coindesk
While more specialized hardware is beginning to come to market, you’re probably safe picking one of these scrypt currencies to mine. Ethereum is a good choice, so that’s what I’m going to start with.
The tools
To get started mining, you need ethereum, a miner, and a wallet to send the mined coins to.
First, enable the ethereum repository:
sudo add-apt-repository -y ppa:ethereum/ethereum
sudo apt-get update
Then, install ethereum:
sudo apt-get install ethereum
Next, you need to install the miner, ethminer. (There are other miners as
well, like qtMiner, cudaminer, eth-proxy). You can either install via apt-get
or from source; because I’m a masochist I chose the latter.
Head on over to the releases page and download the most recent release:
wget
tar xvzf ethminer-0.12.0-Linux.tar.gz
And then try running ethminer. You should see something like:
This is good! It’s working, it just needs to be configured with options.
Finally, the wallet. There’s lots of wallets available, with Mist being the officially supported version. You don’t actually need your wallet to be local; it can be hosted anywhere, including on an exchange like Coinbase.
Pools
Mining cryptocurrencies is kind of like a bunch of people in a field of haystacks looking for needles. Every so often somebody gets lucky and finds one, shouts it out to the world, and makes a chunk of money, and then the process repeats.
This is all well and good for that lucky finder, but — especially nowadays, when you’re competing against industrial-strength mining operations — the chances of you solving a particular cryptographic puzzle first are slim to nil. If you’re a small fry like me, you’re better off joining a mining pool.
A mining pool allows a group of miners’ computers to join forces and work on earning cryptocurrency as a team. When a new coin is mined, the profits will be shared with the contributors based on the amount of computing power they put in.
https://www.buybitcoinworldwide.com/ethereum/mining-pools/
ethermine
The first pool I joined was ethpool, and I subsequently switched to ethermine (which appears to be running the same code? it’s unclear) as their payout scheme was more predictable.
To start up mining, I ran:
./ethminer --farm-recheck 200 --cuda-parallel-hash 8 --cuda-grid-size 1024 --cuda-streams 16 --cuda-block-size 128 -G -S us1.ethermine.org:4444 -FS eu1.ethermine.org:4444 -O <My_Ethereum_Address>.<My_RigName>
Here’s the definitions for each option:
farm-recheck—Leave n ms between checks for changed work (default: 500). When using stratum, use a high value (i.e. 2000) to get more stable hashrate output cuda-parallel-hash—** ***Define how many hashes to calculate in a kernel, can be scaled to achieve better performance. Default=4*cuda-block-size— Set the CUDA block work size. Default is 128cuda-grid-size— Set the CUDA grid size. Default is 8192cuda-streams— Set the number of CUDA streams. Default is 2
My understanding of farm-recheck is, it’s an for option to set how often the
program checks
for new work to work through. The lower you set it, the lower the chances of
working on stale blocks, but set it too low and you might see instability in the
hashing output.
The other options I’m not 100% familiar with, and so I just went with the defaults. Feel free to leave a comment if you have a plain english explanation of them.
Finally, you’ll pick the servers to connect to — I chose us1and eu1 — and
finally put in your wallet address and a name to identify your mining computer.
You may need to open up the ports 4444 on your machine to allow connections.
If you’re having trouble with ethminer, there’s an active Gitter room as well.
Once you start mining, you can go to your miner page and check out your stats. For instance, the dashboard view shows:
Which gives you a nice overview of your stats, and also a rough estimate of your payouts:
Tuning
Once you’ve got your rig mining, you may want to squeeze out every ounce of processing power. If so, here’s a few links to point you in the right direction!
The awesome wiki article at /r/EtherMining:
https://www.reddit.com/r/EtherMining/wiki/index
A conversation on overclocking:
https://bitcointalk.org/index.php?topic=1712831.0
A few articles about tweaking miners:
http://cryptomining-blog.com/7341-how-to-squeeze-some-extra-performance-mining-ethereum-on-nvidia/
How about writing your own miner?
And that’s what you need to get a mining rig set up! Piece of cake, right? The good news is once it’s set up you can just sort of let it run without touching it. Just make sure nobody trips over the power cable.
The final installment of this series will be about getting some basic AI learning algorithms running on the hardware. If you want to hear about those, drop your email below and I’ll let you know when I publish it!