The protocol can only ensure that such an attack would be very costly to pull off.
Hi, @mrsmkl , sorry for bother you again... Recently I found that
libpbc didn't meet my needs because the curves it supports are not used by ETH. Thus, I have to use another library published in https://github.com/herumi/ate-pairing. In the beginning, the emmake make command reports error: unknown FP unit 'sse', and I found a flag in the Makefile causes this. So, I delete the flag, and rebuild the code. And it reports following error. I personally think it not caused by the deleted flag. it looks like the compiler cannot find 64-bit version head file, and, instead, using 32-bit head file.
@mrsmkl I download the libff, find that it also depends on ate-pairing. And I check the script
libff.sh in https://github.com/TrueBitFoundation/wasm-ports/blob/master/libff.sh, however, the script doesn't download the dependents... like running git submodule init && git submodule update. So the script ignore this command....
And I replace the flag
-m64 by -m32 in ate-pairing, the error is following.
libff has also another implementation for bn128, see https://github.com/scipr-lab/libff#elliptic-curve-choices
Hi @mrsmkl , I test
libff installed in docker by the code provided in https://github.com/scipr-lab/libff/blob/f2067162520f91438b44e71a2cab2362f1c3cab4/libff/algebra/curves/tests/test_bilinearity.cpp, with the command: em++ test.cpp -s WASM=1 -lgmp -lff -I $EMSCRIPTEN/sysytem/include -std=c++11 -o test.js. When I use node run the test.js, it returns following result...
What does this error mean?
but the problem is that profiling code calls some weird functions, if they are disabled, it works
We must to establish a market price for TRU, relative to the true cost of electricity per CPU cycle, in order to price a task. I believe that the Task Giver sets the price in the current implementation, but we'll need to enforce a lower bound on mainnet because underpricing a task eliminates the incentive for verification. In the long run, the task pricing mechanism must be decentralized.
@teutsch Thank you for your explanation! Let me repeat it again. If there is a problem with my understanding, please point it out. In general, it is similar to "the market" in the economics which determines the price of commodity. Ideally, all participants, including Task Givers and Solvers in Truebit, will agree on the price of per CPU cycle, which is somewhat similar to gasPrice in Ethemum which floats around 8 Gwei. However, it seems the computational capacity still is bounded, since the total TRU consumption is related to the total CPU cycle used. is it somewhat similar to the gas in Ethereum?
And one more question, is there any tools can tell me how much CPU cycle a task will take?
The payment does come from the jackpot, but the jackpot is funded by the Task Giver. The Task Giver pays the Verifiers' expected reward so that the expected capital in the Jackpot Repository tends toward a constant over time. If tasks would be free to the Task Giver, this would probably induce spam. Then Verifiers could issue tasks that they already knew the answers to and get rich from solving them without doing any work. In this scenario, there is then little incentive to instead perform "real" tasks that involve actual work.
In my understanding, what a Task Giver have to pay are 1) the reward for solving task, 2) the tax to be added into jackport repository. The reward must higher than the indeed cost of a task which is metered by CPU cycle of the task. The tax is for 1) maintaining the jackport repository in a constant value, 2) preventing some attacker from spamming. We believe that the price of per CPU cycle will be a reasonable price, compared with gasPrice in Ethereum, thus we can say the execution of complex task in Truebit is much more cheaper than in Ethereum.
In my paper, I want to convince the reviewers that the cost of computation can be indeed reduced through Truebit, but I have no ideas to prove it... Could you give me some advice? Is it feasible to measure the task execution time and estimate the amount of money that this task might cost with the unit price of cloud computing, like Amazon EC2?
@mrsmkl may be able to give you some benchmarks on the overhead for the new JIT compiler vs. native code. Truebit JIT might be less expensive than EC2, however EC2 probably has better performance. Do you have any specific tasks you'd like to run on EC2, and can you estimate their dollar costs?
Sorry for my bad expression. What I mean is I want to prove the gas consumption in Ehtereum can be reduced through Truebit. Currently, the execution of my smart contract costs about 30 million gas, which is very infeasible. I want to give a proof that the money for executing a task is cheaper. So I wander can I use the unit price of EC2 to measure how much a Truebit task might cost, since we don't know the price of a CPU cycle currently, and the price of EC2 looks like a acceptable standard.
sometimes it's possible to collect several tasks into a batch, then the transaction costs will not increase
Hi Team,
Could you please enable github issue for below repository. I wanted to initiate a discussion on the repository.
https://github.com/TrueBitFoundation/eth-patricia
Thanks
please test the latest docker image: https://github.com/TrueBitFoundation/truebit-os#running-on-docker ... trying to have a stable version now that can be used for developing Truebit tasks