Topic: Faster SHA-256, MSVC build (Read 15647 times)

The C7 version of bitcoin should work well on the Nano even if it is just a 32 bit mode, not 64. You might recompile it for 64 bit on a Nano and see if it still works right.

The code has improved since my previous post, and my machine now gets about 1800 khash/s at 50 W. Nevertheless, Via C7 remains more efficient. In fact, I am considering getting a Via Nano motherboard, there is even a Mini-ITX model with a full PCIe slot.

I measured my VIA-C7 at the plug at 27 watts including 2 hard drives. With the SHA256 instruction support (I added) in bitcoin it gets 1430 khash/s @1.8 GHz so it seems like a pretty good improvement in power efficiency.

Interestingly this build even gives my old Ubuntu Core Duo 32 bit a pretty hefty boost. In Wine no less !
Native client 0.3.3 = 602 kHash/s, MSVC build 0.3.3 (+ Wine) 771 kHash/s.

VIA declares they have the best performance/watt at the market. Having cryptoaccelerator it could be even better for applications like bitcoin

AMD also has something on their Geode processor. It's even slower then VIA, but the complete system on it consumes about 5 Watt energy. I used to have such router built on top of Alix PC hardware.

For a single point of comparison, my Core 2 Duo system consumes 50 watts while computing just a little over 1000 khash/s. VIA Mini-ITX systems may consume a little less than this (note, entire system, not just the mobo + CPU) so they would be somewhat better, but not hugely so.

Nice! I don't know if it would "pay off" the electricity it uses but it would be a great extra node on the network and low power at that. My next project aims to take this even a step further and lower, right into a chip to crunch and run the program.

Sounds cool I also have a VIA processor running my router/bittorrent stuff at 24/7 mode. Having your code I know how to make it busy while it idles Maybe it will be able to compensate the electricity it consumes :DDD

falkenberg,

I have a VIA C7 that I'm working to port code over to. Theoretically it won't be faster than multi-core i7/xeons but it will be a very fast hashing engine that require quite low power. From what I've calculated, it would be able to compute about 1500kh/s for < 100W. We won't know until I get it setup and running


sgtstein

Hi guys,
what about the cryptoengines, available on some architectures? Ie PADLock on a VIA processor (yeah, it's a very slow processor, but has padlock instructions)? As far as I know SHA-256 is backed upped by the hardware and must be fast.  Last versions of OpenSSL can benefit from hardware engine, so if it used instead of your own SHA-256 implementation you can accelerate the program without dealing with low-level details.

Regards,

is this the x86 asm? I dumped out the x64 asm and integrated it and performance has proved to be nothing short of blistering.

Is it easy for a newb to try this stuff?

Excellent work.

Can you provide patches against current SVN?

I was able to integrate the SHA256 functionality from Crypto++ 5.6.0 into Bitcoin.  This is the fastest SHA256 yet using the SSE2 assembly code.  Since Bitcoin was sending unaligned data to the block hash function, I had to change the MOVDQA instruction to MOVDQU.

I think using the SHA256 functionality from Crypto++ 5.6.0 is the way forward right now.

http://www.filedropper.com/bitcoin-033

Found the culprit. I had left in the  /Ob0 option from the original makefile, which obviously led to the abysmal performance I was getting. With proper settings, the VC++ build is really faster. This tinkering with makefiles is a major hassle, I'm going to suggest converting to CMake in another post.

Regarding the SHA-256 function, we can:

1) leave it as it is - requires no effort, but it seems other solutions provide significant performance benefits;

2) adopt the SHA-256 code from later releases of Crypto++; an asm version is currently available; we have the option to either extract the functionality from modules and integrate it into bitcoin source as currently done, which would not be trivial for all SHA module dependencies, or use the complete Crypto++ library as a dependency. No one has done either yet as far as I know, so it is not clear how much faster will it be. More interestingly, I've skimmed the change logs and there are various fixes in Crypto++'s sha module as well. I'm not certain if there are any serious problems with the code bitcoin is currently using though.

3) Integrate code from PolarSSL, like BlackEye did. He claims a 50% khash/s increase with that code.

If we choose either of the last two options, we need to take great care that the hashing functionality is preserved without change or breaking anything. Unit tests would greatly help here, but for that the sha-invoking code in bitcoin would need to be extracted to a separate unit which can be tested.

I could do that refactoring, create unit tests for the hashing and provide patches. Then we can more freely experiment with upgrading the sha implementation. Satoshi and/or anyone interested, post your thoughts.

Yes, my post clearly says I used the latest BDB which will update the database format, and you should backup your database beforehand.  I just used the latest production release from the Oracle website, and I didn't see any version requirement in the documentation about compiling Bitcoin.  If you look at the BDB release notes, there were plenty of bugs squashed since whatever 4.7.x release Bitcoin is currently using.  What was the rationale of using an outdated version for the official release?

edit
Here's a release statically linked against BDB 4.7.25, so there will be no issues with database versions.
http://www.filedropper.com/bitcoin-032_4

bit of a shame you linked it against BerkeleyDB5, that will break everyone's database if they should wish to go back to the stock build.

The project file is attached.  You'll need to remove the txt extension and change the paths to your libraries, and compile the Release build of course, not the Debug one.

If you are using the Express edition to compile, make sure to read this thread on msdn.

It's baffling. Do you mind posting the makefile/project you used to build the original source?

A 32 bit build running on a 32 bit system with the new algorithm is definitely faster than the base algorithm.  I've ran it on 3 different systems and all showed improvement.