New demonstration CPU miner available

[jgarzik]

A new CPU miner is now available, making use of the new 'getwork' RPC command.

In the beginning, this is intended largely to demonstrate a 'getwork' miner.  It is written in straight C, with minimal dependencies (libcurl, jansson).

It has successfully generated blocks on testnet, mainnet and almost all pools.

Linux/BSD release tarball: http://yyz.us/bitcoin/cpuminer-1.0.2.tar.gz
Windows installer: http://yyz.us/bitcoin/cpuminer-installer-1.0.2.zip
git repository: git://github.com/jgarzik/cpuminer.git

Contributions welcomed!  (GPL v2 license)

UPDATE:  This has largely been superceded by Con Kolivas's cgminer fork.  See cgminer's official forum thread for updates and details.

[slush]

In the beginning, this is intended largely to demonstrate a 'getwork' miner.  It is written in straight C, with minimal dependencies (libcurl, libcrypto, jansson).

Cool, I like simplicity of your code. I want to try similar implementation in javascript. Partially because of curiosity and partialy because (inspired by hashcash) it can generate few hashes by fighting comments spam :-).

I just made few tests. In four javascript threads I get ~4khash/s, which is EXTREMELY slow. Probably because javascript is interpreted and without any JIT yet. Would be great if javascript supports GPU. Flash will support GPU soon, so we will see .

[sturle]

In the beginning, this is intended largely to demonstrate a 'getwork' miner.  It is written in straight C, with minimal dependencies (libcurl, libcrypto, jansson).

Cool, I like simplicity of your code. I want to try similar implementation in javascript. Partially because of curiosity and partialy because (inspired by hashcash) it can generate few hashes by fighting comments spam :-).

I just made few tests. In four javascript threads I get ~4khash/s, which is EXTREMELY slow. Probably because javascript is interpreted and without any JIT yet. Would be great if javascript supports GPU. Flash will support GPU soon, so we will see .

Is your JavaScript code available?

I wish the getwork RPC command could be allowed for non-authenticated users from other hosts.  It isn't revealing any secret information, is it?

[wumpus]

Nice idea on the independent C miner.

On the JS one: Oh no, soon all kinds of websites will be sneakily generating bitcons on the background while you browse them, hogging your CPU even more

[slush]

Is your JavaScript code available?

I wish the getwork RPC command could be allowed for non-authenticated users from other hosts.  It isn't revealing any secret information, is it?

Will be available if I finish that. It is just for curiosity because it will be slow as hell. Also network overhead will be significant.

I expect simple PHP proxy will do good work for hiding credentials to client. something like yourdomain.com/getwork.php which call rpc to localhost and return json encoded data.

[wumpus]

Will be available if I finish that. It is just for curiosity because it will be slow as hell. Also network overhead will be significant.

I believe that IE has cryptographic extensions that you can use from javascript. Maybe that will speed it up?

[slush]

I believe that IE has cryptographic extensions that you can use from javascript. Maybe that will speed it up?

 Do you have any link or reference? I found only 3rd party ActiveX component here http://www.chilkatsoft.com/js-sha512-hash.asp.

[teknohog]

Should I use a particular version of jansson? I installed it from git, and get the following compile error:

Code:

util.c: In function ‘json_rpc_call’:
util.c:133:2: warning: passing argument 2 of ‘json_loads’ makes integer from pointer without a cast
/usr/local/include/jansson.h:188:9: note: expected ‘size_t’ but argument is of type ‘struct json_error_t *’
util.c:133:2: error: too few arguments to function ‘json_loads’
/usr/local/include/jansson.h:188:9: note: declared here

[jgarzik]

Nice work.

But :

DBG: found zeroes in hash:
6c1e0d9af9b06eab5aae7fbe058760708c1c7869870142b91b9c0ae300000000
PROOF OF WORK FOUND?  submitting...
PROOF OF WORK RESULT: false (booooo)
[...]
DBG: found zeroes in hash:
c155613cbd70edad88bf56b06cbd788329a2a741b27ee78f25abdb2e00000000
PROOF OF WORK FOUND?  submitting...
PROOF OF WORK RESULT: false (booooo)

I don't know if this is a bug or not.
The miner has been compiled with cygwin, I don't know if it matters.

Not a bug.  The miner finds a hash with "several" zeroes in it, but then relies on bitcoin to do the full 256-bit hash < target value comparison.  It's normal that some hashes will be found by the CPU miner, then rejected by bitcoin.  We call those almost-solutions

[jgarzik]

FWIW, the default bitcoin miner also does this -- it just doesn't print out when it "finds some zeroes", only when a real proof of work is found.

Thus, my CPU miner always shows when it stops working on a solution, and starts working on a new solution.  Just giving you a bit more information on the whole process.

[jgarzik]

Attached is a Windows executable build with mingw32.  I'd be interested to know if it works.

run "minerd.exe --help" or "minerd.exe -h" to show command line options.

minerd.exe SHA-1 sum: 722fa3b956de3ed3438ed3294fe191f0d55c1514
minerd.exe MD5 sum: 9f75f8da7a5d02da1d45d46d4a032489

[jgarzik]

Should I use a particular version of jansson? I installed it from git, and get the following compile error:

Code:

util.c: In function ‘json_rpc_call’:
util.c:133:2: warning: passing argument 2 of ‘json_loads’ makes integer from pointer without a cast
/usr/local/include/jansson.h:188:9: note: expected ‘size_t’ but argument is of type ‘struct json_error_t *’
util.c:133:2: error: too few arguments to function ‘json_loads’
/usr/local/include/jansson.h:188:9: note: declared here

It's been tested with jansson 1.2 and 1.3 release versions.

EDIT:  If you lack jansson, current cpuminer.git will build an in-tree version.  Thus, you may opt to fix the problem by... removing jansson from your system.

[satoshi]

You should try it with tcatm's 4-way SSE2 SHA in sha256.cpp.  It compiles fine as a C file, just rename sha256.cpp to sha256.c.  I was able to get it to work in simple tests on Windows, but not when linked in with Bitcoin.  It may have a better chance of working as part of a C program instead of C++.

Currently it's only enabled in the Linux build, so if you get it to work you could make it available to Windows users.  It's about 100% speedup on AMD CPUs.

[jgarzik]

You should try it with tcatm's 4-way SSE2 SHA in sha256.cpp.  It compiles fine as a C file, just rename sha256.cpp to sha256.c.  I was able to get it to work in simple tests on Windows, but not when linked in with Bitcoin.  It may have a better chance of working as part of a C program instead of C++.

I'll take a look.  VIA Padlock support may also be similarly easy to integrate.

[BitLex]

I'd be interested to see how well this works on Vista, XP, 7, ...

complaining about "libcurl-4.dll missing" (although it's there at c:\CPU-miner\usr\i686-pc-mingw32\sys-root\mingw\bin\) it won't even start on 64bit XP&7, 32bit XP,
am i missing something?

[jgarzik]

I'd be interested to see how well this works on Vista, XP, 7, ...

complaining about "libcurl-4.dll missing" (although it's there at c:\CPU-miner\usr\i686-pc-mingw32\sys-root\mingw\bin\) it won't even start on 64bit XP&7, 32bit XP,
am i missing something?

Try adding c:\CPU-miner\usr\i686-pc-mingw32\sys-root\mingw\bin\ to your PATH, then run minerd.exe?

[slush]

complaining about "libcurl-4.dll missing" (although it's there at c:\CPU-miner\usr\i686-pc-mingw32\sys-root\mingw\bin\) it won't even start on 64bit XP&7, 32bit XP,
am i missing something?

Same here (WinXP)

[jgarzik]

You should try it with tcatm's 4-way SSE2 SHA in sha256.cpp.

Added.  Users may select this by enabling SSE2 instructions in their compiler during build, and then

Code:

$ minerd --algo=4way

will select the 4way implementation, rather than the default 'c' implementation.  Run "minerd --help" to make sure 4way is listed as an available option first; if not, you did not build with SSE2 enabled (-msse2, or many values of -march=xxx).

[jgarzik]

complaining about "libcurl-4.dll missing" (although it's there at c:\CPU-miner\usr\i686-pc-mingw32\sys-root\mingw\bin\) it won't even start on 64bit XP&7, 32bit XP,
am i missing something?

Same here (WinXP)

Clearly my installer-maker is having a problem     Will investigate (though probably tomorrow).

[jgarzik]

I'd be interested to see how well this works on Vista, XP, 7, ...

complaining about "libcurl-4.dll missing" (although it's there at c:\CPU-miner\usr\i686-pc-mingw32\sys-root\mingw\bin\) it won't even start on 64bit XP&7, 32bit XP,
am i missing something?

Updated the installer at http://yyz.us/bitcoin/cpuminer-installer.zip

Does the problem still exist?

EDIT:  Here are the checksums for the latest Windows installer zipfile...
     Size: 1978933 bytes
     SHA1: fdea8a045db5e09b7441a4059fbdba186490e742  
     MD5: e60dbfb7c3b458c2a98e71cb295f9b7d