Category Archives: CryptoCurrency

Bitcoin Mining on Mac OS X – Bitfury ASICS

A new batch of ASICs is hitting the market based on the 55nm Bitfury ASIC chip (abbreviated BF1). The most popular of these are USB sticks branded as either Blue Fury or Red Fury, depending on the color of the onboard LED. The BF1 Fury sticks look very similar to the ASICMINER Block Erupter sticks. However, while the Block Erupters hash at 335Mh/s the new BF1 Fury sticks hash at anywhere from 2.2Gh/s up to 3.0Gh/s.

Red Fury

Miner Installation

As with the ASICMINER Block Erupters, the first step is to install either bfgminer or cgminer on OS X. There are several ways to go about this, from compiling them yourself, to using Homebrew, to downloading precompiled binaries.

There is a thread here on the Bitcoin Talk forums which discusses various ways to install cgminer and bfgminer on Mac OS X. One of the more full-proof methods is to use Homebrew:

  1. Launch Terminal.app from Spotlight or from your Applications folder
  2. Install Homebrew by entering the following command:
    ruby -e "$(curl -fsSL https://raw.github.com/mxcl/homebrew/go/install)"
  3. Run the following command and fix any reported issues:
    brew doctor
  4. Tap this Homebrew repostory so that you can install packages from it:
    brew tap nwoolls/xgminer
  5. Finally, install either cgminer or bfgminer:
    brew install cgminer

If you’d like to install the miner using the latest source from Github rather than the latest official package, use the –HEAD (two dashes prefix) parameter, e.g.:

brew install bfgminer --HEAD

Driver Installation

As with the ASICMINER Block Erupters, bfgminer requires the correct kernel extension to be loaded in order to detect the BF1 Fury stick. And, as with the Block Erupters, cgminer will fail to detect the BF1 Fury stick unless that same kernel extension is unloaded. Unlike with the Block Erupter there is no driver or software to download. When using bfgminer the Apple Communication Device Class (CDC) driver will be used. When using cgminer that driver (kernel extension) must be unloaded.

To load the required Apple drivers (if you intend to use bfgminer) execute the following commands:

sudo kextload -b com.apple.driver.AppleUSBCDC
sudo kextload -b com.apple.driver.AppleUSBCDCACMData

To unload those drivers (if you intend on using cgminer) execute the following:

sudo kextunload -b com.apple.driver.AppleUSBCDC
sudo kextunload -b com.apple.driver.AppleUSBCDCACMData

Detection

Once you have the proper Bitcoin mining software installed and the kernel extensions loaded (or unloaded), you can use the -d? argument to list available devices with bfgminer:

bfgminer -d? -S bigpic:all
[2013-11-21 16:38:38] Started bfgminer 3.6.0
[2013-11-21 16:38:38] Devices detected:
[2013-11-21 16:38:38] 0. BPM 0 (driver: bigpic)
1 devices listed

or with cgminer:

cgminer -d?
[2013-11-21 16:49:06] Started cgminer 3.8.2
[2013-11-21 16:49:09] Devices detected:
[2013-11-21 16:49:09] 0. BF1 0 (driver: bitfury)
[2013-11-21 16:49:09] 1 devices listed

Mining

Once the BF1 Blue Fury or Red Fury is detected you can fire up your chosen miner using the -o, -u and -p arguments to start hashing away:

cgminer -o hostname -u username -p password

Running bfgminer requires an additional -S argument:

bfgminer -S bigpic:all -o hostname -u username -p password

bfgminer Red Fury

Feel free to leave any questions below or on this thread on the Bitcoin Talk forums. And happy mining!

Cryptocoin Mining on Mac OS X – Wallet Backups

If you’ve taken cryptocoin mining beyond the hobby stages, you probably have at least one digital wallet on your system – possibly several. What happens if your OS were to crash? If you were to reinstall? Where would your accumulated cryptocurrency be?

Gone.

It is very important that you backup the private keys that secure your digital wallet so that you can restore them at a later time. Otherwise the keys required to claim ownership of your coins will be gone forever. It is also important that you backup your wallets regularly. It is not enough to backup your keys just once. See this entry on securing the bitcoind wallet for more details.

So what steps can you take on Mac OS X to keep your wallets backed up? Luckily OS X comes with several tools that help along the way. Additionally, the Unix foundation of OS X allows us to fall back on some time-tested solutions for this project.

Step One – Create an Encrypted Disk Image

Step one will be to create an encrypted disk image used to store the wallet.dat backups. This is what Steve Gibson refers to as “Pre-Internet Encryption” – encrypting important data before backing it up to the Web.

  1. Launch Disk Utility from the Applications folder
  2. Click New Image
  3. Save the image somewhere that is itself backed up (e.g. Dropbox or Wuala)
  4. For the name, specify Wallet Backups (so that the below scripts match)
  5. For Encryption, select either 128 or 256 (256 is more secure and should be plenty fast for this)
  6. Click Create

New Disk Image

Step Two – Create a Backup Script

Now that we have a secure place to store wallet backups, the next step is to create a script that will do the grunt-work. Namely it should mount the encrypted disk image, backup any wallet.dat files (we could have Bitcoin, Litecoin, and who knows what other digital wallets – get them all), and then unmount the encrypted image.

We can do all of this with Automator and a couple of shell scripts.

  1. Launch Automator from the Applications folder
  2. Select Application and click Choose
  3. Add a Get Specified Finder Items action
  4. Select the DMG file created in Step One
  5. Add a Mount Disk Image action
  6. Add a Run Shell Script action and enter:
    cd ~/Library/Application\ Support && rsync -R ./*/wallet.dat /Volumes/Wallet\ Backups/
  7. Add another Run Shell Script action and enter:
    diskutil unmount /Volumes/Wallet\ Backups/
  8. Click File, Save
  9. Save as BackupWallets.app in Applications

Complete Automator Application

Step Three – Schedule the Backup

Armed with encrypted storage and a backup script, the only thing left is to schedule the backup. The Unix foundation of OS X means we can do this by editing the system crontab, a configuration file that specifies the commands to run for cron, the Unix job scheduler.

  1. Launch Terminal from the Applications folder
  2. Enter the following and press Return:
    export EDITOR=nano && crontab -e
  3. Enter the following into the nano editor:
    # backup wallets at midnight every Sunday
    0 0 * * 0 open /Applications/BackupWallets.app
  4. Type Ctrl+X, Y, Return

crontab

Conclusion

And we’re done. You can check your disk image each Sunday after midnight to ensure that your wallets have been backed up. You can also run the BackupWallets.app application to backup your wallets on-demand.

Bitcoin Mining on Mac OS X – ASICs

While it’s been possible to purchase ASICs (Application Specific Integrated Circuits – chips specifically created to mine Bitcoins in this case) for several months, it has been a difficult and risky process involving auctions on forums with one-way exchanges of money for promises of future hardware. However, recently ASICMINER has made it much easier to purchase their Blades and USB miners. You can pick up one of the USB ASIC miners for around $90 USD (at current exchange rates). One of these will hash at around 333 Mh/s at a fraction of the power usage of modern GPUs.

USB Block Erupter

Installation

To get started using a USB ASIC under OS X, such as the Block Erupter from ASICMINER, you will first need to install either cgminer or bfgminer. You can refer to my previous article for details on installing cgminer or bfgminer under OS X. The basic steps are:

  1. Launch Terminal.app from Spotlight or your Applications folder
  2. Install Homebrew by entering the following command:
    ruby -e "$(curl -fsSL https://raw.github.com/mxcl/homebrew/go)"
  3. Run the following command and fix any reported issues:
    brew doctor
  4. Tap this Homebrew repostory so that you can install packages from it:
    brew tap nwoolls/xgminer
  5. Finally, install either cgminer or bfgminer:
    brew install cgminer

If you’d like to install the miner using the latest source from Github rather than the latest official package, use the –HEAD (two dashes prefix) parameter, e.g.:

brew install bfgminer --HEAD

NOTE: if you are going to use bfgminer, at this time you must use the above –HEAD parameter to get the latest changes from Github. Otherwise USB devices may not be recognized automatically.

Also, if you are using bfgminer you must install the CP210x USB to UART Bridge VCP driver found here. This driver will break USB support in cgminer. Click here for instructions on removing the driver. If you get a page saying your session timed out, visit the main knowledge base site first, and then navigate to the removal instructions. I’ve also reproduced their instructions below:

To uninstall the VCP driver from a Mac OS machine, just drag the driver to the trash from the System/Library/Extensions folder (SilabsUSBDriver) and then reboot the machine.

To verify if a driver is present, plug in a CP210x device and check the /dev directory for a device named “tty.SLAB_USBtoUART”. If this is not present, it means no VCP driver is active, or that the CP210x device has a VID/PID combination that does not match the driver installed. The VID/PID can be found in the device listing in the System Profiler (even if a corresponding driver is not installed).

Detection

Once you have successfully installed one of the above Bitcoin miners, use the following commands to probe for the ASIC USB devices:

cgminer --ndevs

The above command should show USB details for each Erupter ASIC:

[2013-07-01 17:16:30] USB all: found 18 devices - listing known devices
.USB dev 0: Bus 58 Device 2 ID: 10c4:ea60
Manufacturer: 'Silicon Labs'
Product: 'CP2102 USB to UART Bridge Controller'
.USB dev 1: Bus 93 Device 2 ID: 10c4:ea60
Manufacturer: 'Silicon Labs'
Product: 'CP2102 USB to UART Bridge Controller'
[2013-07-01 17:16:30] 2 known USB devices

For bfgminer, use the following command:

bfgminer -S all -d?

The bfgminer output should show ICA devices for the Erupter ASIC:

[2013-07-01 17:15:12] Started bfgminer 3.1.1
[2013-07-01 17:15:17] Devices detected:
[2013-07-01 17:15:17] 0. OCL 0 (driver: opencl)
[2013-07-01 17:15:17] 1. OCL 1 (driver: opencl)
[2013-07-01 17:15:17] 2. ICA 0 (driver: icarus)
[2013-07-01 17:15:17] 3. ICA 1 (driver: icarus)
[2013-07-01 17:15:17] 4 devices listed

Mining

Finally, once you have ensured the miner is recognizing your ASIC, you can start mining with it. You can start cgminer without any special parameters:

cgminer -o hostname -u username -p password

Or start bfgminer with the -S all parameter:

bfgminer -o hostname -u username -p password -S all

cgminer USB Erupter

If you run into any issues you can leave comments below. However, if your issues are specific to cgminer or bfgminer you can find specific forum threads for them here and here.

UPDATE: Several readers have asked how to mine using only their ASIC devices and not their GPUs. Both cgminer and bfgminer support the –disable-gpu (two dashes prefix) argument:

cgminer -o hostname -u username -p password --disable-gpu
bfgminer -o hostname -u username -p password -S all --disable-gpu

Bitcoin & Litecoin Proxy Mining on Mac OS X

Bitcoin

When it comes to mining Bitcoins and Litecoins there are two major protocols involved: the older Getwork protocol and the newer Stratum protocol. At this point the Stratum protocol has all-but-replaced the Getwork protocol. All major mining pools and mining software support Stratum and Getwork is deprecated.

This is usually not a problem, however some older mining utilities (for example the Litecoin CPU miner) do not have Stratum support. And some pools, such as Slush’s Bitcoin pool or WeMineLTC, have limited-to-no support for Getwork. This is where a very nice Python utility called the Stratum Mining Proxy can help.

You can use the Stratum Mining Proxy on any computer to connect to your desired Bitcoin or Litecoin pool. Then you can connect your mining software to the IP address of the computer the proxy mining software is running on. All of the Getwork network requests from the mining software will be reshaped into the Stratum protocol and then forwarded on to the mining pool.

Installing the Xcode Command Line Tools

In order to install the mining proxy you’ll need a set of command line utilities for compiling software. You have two options:

  1. Install Xcode for free from the App Store and then use Xcode to install the Command Line Tools package
  2. Install only the Command Line Tools package from an unofficial (non-Apple) source

If you would rather play it safe and stick to as many trusted sources as possible, or if you plan to make use of the Xcode IDE, go with the first option. If you’d rather save some disk space and don’t mind using a widely used – if unofficial – source, go with option two.

Option 1: Install Xcode and Command Line Tools

To get started using this option you will need to install the Xcode. Xcode is a free download from the Apple App Store.

Xcode on App Store

Next you’ll use Xcode to install the Command Line Tools. Launch Xcode and then click the Xcode>Preferences menu item. Click the Downloads tab and then click Install next to Command Line Tools.

Xcode Downloads

If the text next to Xcode Command Line Tools says Installed, carry on to the next step.

Option 2: Install just the Command Line Tools

If you would like to install only the GCC Command Line Tools you can download the package for your version of OS X here.

Standalone GCC Installer

Simply run the setup package after downloading and step through the installer.

Downloading the Mining Proxy

The original Stratum Mining Proxy project was created by Slush, who also runs one of the more popular mining pools and is very involved in the Bitcoin community and development, from proposing the concept of pooled mining to proposing the Stratum protocol.

However his original project is for Bitcoin miners and pools only. In order to support both Bitcoin and Litecoin mining you’ll want to refer to this fork which includes support for the scrypt algorithm used by Litecoin. You can either download the latest source as a zip file or use Git to clone the repository.

Installing Scrypt (Litecoin) Support

If you downloaded a zip file of the mining proxy source rather than using Git to clone the repository, extract the zip file contents by double-clicking.

Next, open Terminal.app from the Applications folder or using Spotlight. Use the cd command to navigate to the mining proxy source. For instance, if you downloaded the source as a zip file:

cd ~/Downloads/stratum-mining-proxy-master

Next, change directory to the Litecoin scrypt module:

cd litecoin_scrypt

Finally, install the scrypt module for Litecoin support:

sudo python setup.py install

Installing the Stratum Mining Proxy

Now, in the Terminal app window change the working directory back up to the root of the mining proxy source:

cd ..

And finally install the mining proxy:

sudo python setup.py install

Install Mining Proxy

Using the Mining Proxy

Once the mining proxy is installed, using it is fairly straight forward. Normally your Bitcoin or Litecoin miner connects to a host and port with a specific username and password. For instance:

minerd -o http://pool-host:pool-port -u pool-username -p pool-password -t thread-count

With the mining proxy you’ll want to first run the proxy itself, connecting to the pool’s host and port:

mining_proxy.py -nm -o pool-host -p pool-port

If you are mining Litecoins, use the -pa parameter:

mining_proxy.py -nm -pa scrypt -o pool-host -p pool-port

Mining Proxy Output

Then run your miner, but specify your computer’s IP address and the port number reported by the mining proxy output:

minerd -o http://your-ip:port-from-output -u pool-username -p pool-password -t thread-count

Mining Proxy Output - Clients

Other Benefits

There are a couple of other benefits of the Stratum Mining Proxy that are worth noting:

  1. The mining proxy supports both Getwork and Stratum clients. This means you can use the proxy to consolidate network traffic regardless of the mining protocol.
  2. Using the mining proxy gives you a simple way to get a heads-up view of which machines are alive and which are submitting accepted work by referring to the Terminal output.

Resources

To learn more about mining Bitcoins and Litecoins on OS X, see my previous blog posts:

Bitcoin Mining – Part 1
Bitcoin Mining – Part 2
Bitcoin Mining – Part 3
Litecoin Mining – Part 1
Litecoin Mining – Part 2

Litecoin Mining on Mac OS X – GPU Mining

Litecoin Logo

My previous article on Litecoin mining I discussed how you can get started mining Litecoins, an alternative to the Bitcoin crypto-currency, using your spare CPU cycles. If you’re GPU is already mining Bitcoins, using your CPU to mine Litecoins may be an obvious choice. However, if you are “all in” on Litecoin then you can get a sizable performance increase by using your GPU to mine Litecoins. Whether that trade-off is worth-while is a decision you would need to make. Litecoin is not as mature as Bitcoin and is just as volatile. Some see it as a doomed clone, others as the next Bitcoin, poised to take off.

GPU Mining

In order to start using your GPU to mine Litecoins on OS X, you’ll need to first install cgminer or bfgminer. Please read my previous article on Bitcoin mining for step-by-step instructions and installation packages for cgminer and bfgminer. The Homebrew formulas I shared in my previous article include the configuration settings necessary to mine both Bitcoins and Litecoins. If you are compiling the applications yourself, make sure to use the –enable-scrypt parameter when running ./configure.

Armed with a copy of cgminer or bfgminer with scrypt enabled, you can now start mining Litecoins with your GPU. Now a fair warning: finding a nice set of parameters for mining Litecoins with cgminer or bfgminer is far more finicky and time consuming. With Bitcoins you can basically run either miner and just specify your pool. The miner will then tune itself and eventually reach a nice hash-rate.

This isn’t really the case with using either miner to mine Litecoins. For instance, if I use the following command line to mine Litecoins using my ATI 5770. Note that I am using the -d parameter to specify which GPU to use to simplify these examples.

cgminer --scrypt -o host:port -u username -p password -d 0

cgminer No Params

With no additional tuning my 5770 gets about 5Kh/s. My CPU alone gets around 29Kh/s. Using bfgminer with the basic command-line parameters yields similar results. As indicated in my previous article I use the –no-opencl-binaries to work around a crash in bfgminer with multiple GPU’s on OS X.

bfgminer --scrypt -o host:port -u username -p password -d 0 --no-opencl-binaries

bfgminer No Params

So how can we get better performance mining Litecoins on the GPU? The first parameter to focus on is the -I parameter, or the intensity. With Bitcoin this parameter does help, but honestly not a ton. If you aren’t using the PC, and you leave the intensity at “Desktop” (-I d), both cgminer and bfgminer will eventually reach around the same performance you’d get by specifying something like -I 9.

This is not the case with Litecoin mining. With scrypt (Litecoin’s hashing algorithm) you need to specify a high intensity, in fact higher than is suggested for Bitcoin. I’d start at around 10 and go up from there. On my system, 15-16 is about the best I can do.

So lets try cgminer with -I 13 to see what that does:

cgminer --scrypt -o host:port -u username -p password -d 0 -I 13

cgminer with I

That change alone triples the Kh/s, but from 5Kh/s to 15Kh/s honestly isn’t much to brag about. Let’s try with bfgminer:

bfgminer --scrypt -o host:port -u username -p password -d 0 --no-opencl-binaries -I 13

bfgminer with I

Similarly I get around 14Kh/s using the -I 13 parameter with bfgminer.

The next parameter to focus on is the -w parameter, which specifies a worksize in multiples of 64 up to 256. This parameter is what really makes a difference on my OS X rig:

cgminer --scrypt -o host:port -u username -p password -d 0 -I 13 -w 64

cgminer with I w

Now we’re cooking with Crisco! Using -I 13 -w 64 on my 5770 gets me from the original 5Kh/s up to 83Kh/s with cgminer. And with bfgminer?

bfgminer --scrypt -o host:port -u username -p password -d 0 --no-opencl-binaries -I 13 -w 64

bfgminer with I w

This gets us up to around 80 Kh/s with bfgminer as well. By removing the -d parameter so that both GPU’s are used and cranking up the -I parameter to 16 I can get my GPU’s up to around 230 Kh/s:

cgminer --scrypt -o host:port -u username -p password -I 16 -w 64

cgminer Two GPUs

The last parameter I want to note is –thread-concurrency. If cgminer or bfgminer are reporting hardware errors (the HW number in the output) this indicates that you need to make use of the –thread-concurrency parameter. These are not hardware failures. You can find guidelines for the value to use here:

57xx cards: 2368-4096 (3200 is common)
58xx cards: 4096-8192 (5600, 7168, and 8000 are common)
5970 cards: 4096-8192 (5632 or 8000 are common)

67xx cards: 2368-4096 (3200 is common)
68xx cards: 3008-6720 (4800 is common)
69xx cards: 4096-8192 (5600, 7168, and 8000 are common)
6990 cards: 4096-8192 (5632 or 8000 are common)

7xxx cards: 64 * bus-width-of-card-in-bits. So, for a 7950, that would be 64 * 384 = 24576. Ideal values are 21712 or 24000. Find your bus width here.

I verified that 3200 works well with a 5770 and 4800 works well with a 6870.

Conclusion

And that about covers it for my series of articles on mining Bitcoins and Litecoins using Mac OS X and Apple hardware. The growing landscape of crypto-currency is fascinating from many perspectives. If your interest is piqued and you are running OS X, hopefully you now have the information you need in order to get started mining this new form of currency.

Litecoin Mining on Mac OS X – CPU Mining

Litecoin Logo

My previous series of articles on crypto-currency covered Bitcoin mining on OS X. This series will focus on mining Litecoins. While Bitcoin has been getting the lion’s share of media attention lately with its recent bubbles and crashes and growing adoption, Litecoin has been slowly growing in popularity among alternative crypto-currencies (known as altcoins).

What is Litecoin you may ask? Litecoin is a fork of the Bitcoin project with three important changes:

  1. The hashing algorithm uses is Scrypt rather than SHA-256
  2. Blocks are approved four times faster than Bitcoin blocks
  3. Litecoin is setup to produce 84 million Litecoins, versus Bitcoin’s 21 million target

Proponents of Litecoin argue that Litecoin should be regarded as silver to Bitcoin’s gold: easier and faster to transact smaller amounts. Proponents also argue that, by basing the proof-of-work on Scrypt rather than SHA-256, Litecoin mining will remain in the realm of consumer hardware, rather than limited to mining-specific hardware (like Bitcoin with FPGA’s and ASIC’s). While SHA-256 benefits from massive, parallel processing, Scrypt is built to be very memory-intensive. This means that, for the time being, mining Litecoins using your CPU (which is no longer profitable with Bitcoin) is still possible. You can also use your GPU to mine Litecoins, which gives me a 5x performance boost over CPU mining.

One popular setup seems to be using your GPU’s to mine Bitcoins and use spare CPU power to mine Litecoins. This article will cover how you can use Mac OS X to mine Litecoins using your CPU. If you’re interested in harnessing your GPU’s power to mine Litecoins rather than Bitcoins, a future article will cover that topic.

CPU Mining

To get started with Litecoin mining on OS X, download the official Litecoin wallet application – Litecoin-QT – from the Litecoin website. With the Litecoin wallet you can actually mine from within the UI. Download the DMG file and drag the Litecoin-QT app to your Applications folder.

Litecoin QT DMG

Now, I didn’t cover wallet setup in my Bitcoin series as it was outside the scope of mining. However, as Litecoin CPU mining is generally done within the wallet application (though it can be done at the command-line), I want to make two things clear. First, encrypt your wallet. Second, double-check that the encryption phrase you’ve recorded is correct and works before you start making deposits. The same thing goes for your Bitcoin wallet.

As stated above, the Litecoin wallet UI is capable of showing and controlling mining. While the Litecoin wallet has built in support for solo mining, pooled mining requires another download (see my first article for a brief overview of mining pools). The download is from a project called cpuminer. The cpuminer project was originally a CPU miner for both Bitcoin and then for Litecoin, when CPU mining for Bitcoin was still sensible. These days it’s been replaced in the Bitcoin world by cgminer and bfgminer, and is used in the Litecoin world for CPU mining. You can download the OS X binary for this cpuminer fork directly from the project’s GitHub downloads (32-bit, 64-bit).

Once you’ve downloaded and extracted the cpuminer binary, called minerd, place it alongside the Litecoin-QT app in your Applications folder. This makes it possible to use the pooled miner from within the Litecoin wallet.

UPDATE: The Mining tab has been removed from the Lightcoin-QT wallet. Skip down a couple of paragraphs for details on mining from the command-line.

Now you’re ready to start mining. Switch to the Mining tab in Litecoin-QT. Change the Type to Pool Mining. Set the Threads value to the number of cores you have (double that if you have Hyper-threading). You can leave the Scantime value. It is only used if the mining pool doesn’t support long-polling, which is rarely the case these days. For the Server, Port, Username and Password, enter your mining pool information. Using P2Pool mining pools is fairly popular with Litecoin. You can use p2pool.org or any number of alternatives.

Once you’ve got your mining pool information filled in, click Start Mining to get started.

Litecoin QT Mining

The Litecoin-QT UI will display the output from minerd and a running total of accepted and rejected shares, as well as average hashes-per-second.

Command-Line Mining

Now, if you’re the kind of gal (or guy) who prefers to do your work at the command-line, it’s not required that you use the Litecoin wallet app. While mining from within the app is nice as it gives you running totals, you can just as easily mine from the command-line with the following command:

./minerd -o http://host:port -u username -p password -t thread-count

Command Line LTC Mining

What’s Next?

In the follow-up to this article I’ll discuss the utilities, steps, and tweaks necessary to mine Litecoins on OS X using your GPU. While this doesn’t give the same magnitude of increased performance found when mining Bitcoins on the GPU versus CPU, the increase is still enough to make GPU’s the preferred way of Litecoin mining. However, that also means dedicating GPU cycles to Litecoins rather than Bitcoins, which is a decision you’ll have to make. Litecoins aren’t nearly as established as Bitcoins, so they could be poised to gain in value like Bitcoin has. At the time of this post they trade at around $4 versus Bitcoin hovering around $125). Others call into question Litecoin’s benefits over Bitcoin, seeing it as a doomed clone.

Only time will tell.

UPDATE: If you need to connect the CPU miner to a pool that doesn’t support Getwork, have a look at this post for a solution.

Bitcoin Mining on Mac OS X – cgminer & bfgminer

Bitcoin

In my previous two posts in this series I introduced two easy-to-use bitcoin miners for OS X: BitMinter and GUIMiner. However, while these miners are relatively easy to install and use, they do not offer the best performance when it comes to hash rates. For that you’ll want to look at cgminer and bfgminer. These are native C miners and, paired with the right kernels, their performance exceeds the other two miners by quite a wide margin.

cgminer & bfgminer

The bfgminer project is a fork of the cgminer project. Now, I have no dog in this fight, but my understanding is that the teams aren’t on great terms. However, I have had good luck with both tools and have worked with both authors in order to fix a crash (cgminer, bfgminer) related to multiple GPU’s on OS X and have no complaints whatsoever. Both miners offer similar performance in my experience.

Installation

1. Xcode
To get started, you will need to install the Xcode. Xcode is a free download from the Apple App Store.

Xcode on App Store

2. Command Line Tools
Next you’ll need the Xcode Command Line Tools. Launch Xcode and then click the Xcode>Preferences menu item. Click the Downloads tab and then click Install next to Command Line Tools.

Xcode Downloads

If the text next to Xcode Command Line Tools says Installed, carry on to the next step.

3. Homebrew
Next you’ll need to install Homebrew. Homebrew is a package manager for OS X that provides a sane way of installing *nix tools, libraries, and their dependencies. It is similar to MacPorts for OS X or apt for Linux. Installing Homebrew is super-easy. Open up Terminal.app and run the following command (from the Homebrew homepage):

ruby -e "$(curl -fsSL https://raw.github.com/mxcl/homebrew/go)"

After you install Homebrew, make sure you run the following command (as the installer should instruct you):

brew doctor

Make sure you address any errors or warnings before proceeding as they may prevent the miners from installing.

4. Miners
In my previous post I indicated that it was necessary to compile cgminer and bfgminer from their source code in order to install them on OS X. While that was necessary at the time, after some reading and experimenting with Homebrew I was able to create packages (called formulas with Homebrew) for installing cgminer and bfgminer on OS X 10.8. Once Homebrew is successfully installed, you can run the following commands to install cgminer and bfgminer:

brew tap nwoolls/xgminer
brew install cgminer

or:
brew tap nwoolls/xgminer
brew install bfgminer

If you specify the –HEAD (two dashes) parameter for brew install then the latest source-code will be pulled for the miner from Github rather than using the latest official release.

You can visit the Github repository to view the package contents.

If you run into errors installing the above formulas you can try running brew install with the –debug –verbose parameters to find where things went wrong. I’d also recommend using brew doctor to diagnose any issues.

Usage

Both cgminer and bfgminer are command-line utilities. You can either run them without any command line parameters and fill in the prompts for mining pool URL and credentials or you can use the following format to specify your pool:

cgminer -o http://pool.url:port -u username -p password

or:
bfgminer -o http://pool.url:port -u password -p password

If you have multiple graphics cards you’ll want to use the –no-opencl-binaries parameter with bfgminer to avoid a crash on startup. This is not necessary with cgminer as it detects OS X and applies the same workaround automatically.

Other notable command line parameters are -I (for intensity) and -k (for kernel). If you pass in -I d then the miner will use less resources so you can use your PC (think D for Desktop). Passing in -I 9 is a safe value for having the miner use as much of your graphics resources as possible to mine. Your PC will be much less responsive. Finally, -k lets you specify a kernel. I find on OS X that using -k diablo gives the best performance. So, my command-line using cgminer with the BitMinter pool would look something like this:

cgminer -k diablo -o http://mint.bitminter.com:8332 -u username_workername -p password -I 9

cgminer Hashing

And for bfgminer:

bfgminer -k diablo -o http://mint.bitminter.com:8332 -u username_workername -p password -I 9 --no-opencl-binaries

bfgminer Hashing

Refer to the projects on Github for full documentation of the available command-line parameters.

As you can see from the average in the upper-left of each miner’s output, with cgminer and bfgminer I average 460 Mh/s. Compare that to 400 Mh/s with GUIMiner and 370 Mh/s with BitMinter and you can see why these command-line miners are preferred over their GUI counterparts.

Conclusion

These are exciting times for crypto currency, whether you’re a geek or a speculator or merely a bystander. And, while OS X is pulling up the rear when it comes to supported OS’s for bitcoin mining, hopefully I’ve demonstrated some viable options for getting your feet wet with mining on OS X. BitMinter is a great option for getting started, as it gives you both a bitcoin mining pool with low fees and ready-to-use mining software. GUIMiner is a nice option for improved performance and flexibility in mining pool choice. And, if you’ve decided mining is your thing and you want the absolute best performance out of your rig, you can’t go wrong with cgminer or bfgminer.

UPDATE: Since my original post I’ve had some great help from Bitcoin community member and blogger Kerry on how to get binaries such as cgminer and bfgminer packaged in a self-contained way. If you are interested in the shell scripts that make this possible you can check them out on Github here. I have submitted these scripts to the authors of both cgminer and bfgminer so, in the future, we may see official OS X binary distributions.

In the meantime, if you’d like to try these out instead of following the instructions above, you can download them from the Releases page here.