Bitcoin Forum

Hello,

Yeah I know it sounds a bit strange but I'm looking for a crypto/cpu based (i.e. scrypt/scrypt-jane (read:FTC/YAC)) Javascript miner. I'm in a situation where I have access to about a dozen pc's that I can't install anything on, but they have a browser and I want to put them to work over the weekends.

Google has various suggestions but I haven't found anything yet which is in a usable state.

-Michael

Almost all of the Bitcoin mining options of that kind are either extremely sketchy or have been accused of downloading trojan viruses onto your computer (read: BitcoinPlus).  In addition, the inherent security failures in that technology mean that you really should try mining some altcoin using Javascript, like Powercoin.

can't you just run cpuminer with a .bat script or something like that on start-up, using one thread less that the amount of cores (just to keep the pc responsive)

Yes, as I said I plan to mine a cryptocoin (scrypt/scrypt-jane) which in my case would be either FTC or YAC.

I'm not looking for a site like bitcoinplus, I'm looking for the js code to embed on my own server, which these dummy terminals can then crunch away at over the weekend.

-Michael

As I said I am not able to install software on these pc's. About the only way is something browser based (client side).

-Michael

This would be really cool

for cpuminer you don't need to install software.
just copy the zip, decompress and run a .bat like:
Still to minimize network usage, you'd need to run the stratum proxy pointing properly to where are you mining

C:\guiminer\cpuminer\minerd -a sha256d -o http://server:port -u user -p password -t number_of_threads

I foung something interesting:  "Mining Javascript with WebGL",  maybe it would help?

Thanks for the info.

I am not able to unzip anything. I can't run a .bat file.

Think of a pc running a browser, a la "kiosk mode". I have a web browser, that is all. No dos boxes, no command lines. Just good old internet explorer.

-Michael

I've actually ported the jminer code by pooler (https://github.com/pooler/JMiner) into javascript and managed to get it running. The results are horrible to say the least - i'm sure there could be lots of optimization but the best I could get it to run was about 120 hashes / second or abour 7200 hashes / minute - granted that's on a laptop from 2009. I used a WebWorker - a pseudo thread introduced in HTML5 - to simulate the threads and a basic php proxy to connect the javascript to the stratum proxy running on the server. Even with a single WebWorker the browsers seemed to consume most of my CPU cycles although the browser remained responsive.

At that rate an individual computer would take a very long time to solve even a share of difficulty 1. 5000 computers would have a combined hash rate matching that of a 7950 - i'm not sure if that's a big enough number for the probabilities to take over so that in effect it acts like a single worker - basically one computer would have to get lucky and solve the share very quickly. The more computers you had the better the approximation would be I suppose.

A better approach is outline here - http://bitcoin.biniok.net/gl.html - the developer uses WebGL from Javascript directly to expose the graphics cards. This approach should get much better hash rates but I don't think scrypt is implemented.

If anyone is interested in the javascript cpu miner i would be happy to post it on a git hub page - like i said I only adapted the jminer code by pooler.

See this post:

https://bitcointalk.org/index.php?topic=216966.msg2279073#msg2279073

hehe my pool has a built in web miner

There are several Javascript-based bitcoin miners and they generally get around 0.1MH/s when using multiple threads on an average CPU. But, I realized these javascript codes are not very well written. For this reason, I have started working on a javascript miner ( not java ) a few months ago which can take advantage of just-in-time compilation in the new browsers to achieve a high speedup compared to the existing javascript miners. I performed a lot of code optimization techniques and my preliminary results show more than 10X speed up compared to the best code that I found in internet. This will allow reaching a performance competitive with what can be achieved while running C/Java codes. Please message me if you think this is something that might interest you in any way or if you have any insights.

I run a small minecraft gaming network. Mainly out of curiosity I'm wondering I can create a page where members can donate their cpu to help pay for server expense.

Anyway if you were looking for a community of people to test this with, I have some web/programming skill and would be willing to help out.