[ANN][XEL] Elastic Project - The Decentralized Supercomputer - page 250.

hagie

hero member

Activity: 792

Merit: 501

Quote from: HunterMinerCrafter on September 21, 2016, 12:05:46 PM

(Disclosure: I hold 0 XEL tokens on testnet or genesis roster.)

post your xel and I'll send some testnet tokens - or use the EK's public node to take some.

Regards

HunterMinerCrafter

sr. member

Activity: 434

Merit: 250

P.S.
Can you put grammar source file to github?

Also, something else that I noticed - the JAR files in the github are not bit-identical to those distributed for the libraries elsewhere. This could indicate malware or other tampering, and as such they should probably not be used by anyone at all. (Delete them and download each jar from maven or whatnot if you plan to test this stuff! Better yet rebuild them from source yourself ofc!!)

It would be great if a maven project file were made so that these binaries didn't have to be distributed with quite such a questionable chain of trust behind them? Wink

HunterMinerCrafter

sr. member

Activity: 434

Merit: 250

Is the bounty program officially started yet? What are the criteria?

I have a (growing) laundry list of problems that I see in the implementation...

Let's start with four "easy" bugs in the language parser and vm. I'd like to see these cleaned up to make other analysis easier.

Starting from most simple:

1) Conditionals must always have "else" statement.
The parser allows:

Code:

if(true) {};

but the worstWeight and interpreter will throw ArrayIndexOutOfBounds.
This works:

Code:

if(true) {} else {};

so you need to check the size of conditional statements' children nodes in the vm!

2) Expressions allow mixed bool/int in parser but fail to cast in vm.
For example:

Code:

if(m[0]) {} else {};

throws a "ClassCastException: java.lang.Integer cannot be cast to java.lang.Boolean" in interpreter and:

Code:

m[0] = (true || false);

fails similarly in trying to cast bool to int.
   Either you need to separate bool/int valued expressions in the grammar, or handle casting!
   I'm assuming the intent was to mimic C style int/bool implicit conversion, but this conflicts with the arguably silly Java semantics underlying the VM.

3) Expressions are not IDs...
   However they are treated as such by the parser, which confuses the interpreter.

Code:

(1==0) = 2;

is a nonsense statement allowed by the parser, but resulting (for good reason) in a "ClassCastException: ElasticPL.ASTEQNode cannot be cast to ElasticPL.ASTId" in the interpeter. This seems to be a general problem in the grammar, which does not correctly distinguish Expressions, PrimitiveExpressions, and IDs. Statements such as this should be rejected in parse.

4) Parser allows for arbitrarily large but "0 WCET" programs.
   There seem to be a few problems with the WCET, but this one is by far the "simplest" that I've seen so far. For example, the statement:

Code:

   input 8;
   if(true) {
     repeat(2147483647) {
       SHA256 3 3;
     };
   } else {};
   verify true;

is obviously a "very expensive" program, well above the statement limit constant, which implies that it should be rejected. However, the WCET is calculated as 0, and I doubt anyone will ever find the bounty. (Worse is what happens to the peer nodes if someone does "find" some work/bounty inputs and publishes a PoW/PoB, turning all peer nodes instantly into nothing more than hot/noisy sha mining rig running on a forked chain, hehe...)

(EDIT: Bug #4 is particularly problematic in that with "seemingly" no execution cost, all instances of the reference miner will immediately jump onto this work as the "most profitable." Once you've knocked out all competition like this, you can proceed to claim all legitimate work/bounties for yourself.)

These bugs can be trivially used to disable peer nodes and/or miners. I have more complete examples ready for each if you'd like to see a more detailed confirmation of any.

Let me know when you are ready for more...?

Also, I notice that you see now "some of" the problems with your PoW difficulty mechanism. One or two of our problems "for later" are related to this. One thing which I can say for sure is that the difficulty calculation will need to be made entirely per work order job, as some programs will execute at 200k evals/sec/cpu and some will be 2k evals/sec/cpu and (as things stand right now) some might be 0.0002 evals/sec/cpu. ;-) (I don't have a "workable solution" for how to fix this PoW calculation aspects of your design.)

These are all the least "interesting" (and least fun) of the problems. There seem to be several more, which I'll present in increasing order of "interestingness" assuming that they stick around, but let's see how handling these few easy issues goes first...

(Hey, at least it's not quite as badly broken as when your plan was "Python or Lua" eh?)

(Disclosure: I hold 0 XEL tokens on testnet or genesis roster.)

Evil-Knievel

legendary

Activity: 1260

Merit: 1168

Quote from: provenceday on September 21, 2016, 06:59:51 AM

Quote from: Evil-Knievel on September 18, 2016, 01:47:28 PM

But we really need to think about the POW difficulty scaling.

Maybe we should organize a contest or so! The current scheme (inspired by the Dark Gravity Wave) obviously "sucks".
When you look at the past blocks, we are *faaaaar* from having a steady #10 tx per block, its more kind of oscillating, even though a miner is working constantly without much fluctuation in its computation power.

pls refer to AntiGravityWave (every block), that may inspire you.
https://github.com/viacoin/viacoin/tree/master/src

The biggest problem is that we may have many many miners but no POW for several blocks when there is no work online. When then a new work package is submitted, the difficulty is low again causing many POW submissions to be broadcasted in bursts until the difficulty adapts again.

provenceday

legendary

Activity: 1148

Merit: 1000

Nice to see some great progress.

provenceday

legendary

Activity: 1148

Merit: 1000

Quote from: Evil-Knievel on September 18, 2016, 01:47:28 PM

But we really need to think about the POW difficulty scaling.

Maybe we should organize a contest or so! The current scheme (inspired by the Dark Gravity Wave) obviously "sucks".
When you look at the past blocks, we are *faaaaar* from having a steady #10 tx per block, its more kind of oscillating, even though a miner is working constantly without much fluctuation in its computation power.

pls refer to AntiGravityWave (every block), that may inspire you.
https://github.com/viacoin/viacoin/tree/master/src

tomkat

hero member

Activity: 1022

Merit: 507

Quote from: Evil-Knievel on September 20, 2016, 10:25:04 AM

Quote from: yusyus on September 20, 2016, 10:04:45 AM

Evil-Knievel,
have your team Twitter account for Elastic? to track news about XEL development. tnx

Actually, I think everyone is doing his own stuff here!

One is doing the client, one is doing the website, another one is making a block explorer. We all ("we all is elastic itself, as people come and people go") have the idea behind elastic in mind, and transform our own interpretation of it into code Wink

This means that there is no central authority telling us what to do, and there is also no central authority which gathers weekly status reports to post them on a PR platform.

But this is the fun thing, about Elastic! You can do whatever you want as long as the community accepts it (because if the community does not accept it, it would just ignore it and substitute the specific part with something else)!
So if you feel the need of a twitter page, you can always make one and start collecting updates which you publish there Wink

There is nothing that would stop you from that!

Would be good to see Lannister in action.
I mean a webpage, update of this thread, a promo campaign with signatures, etc.

Redawn

member

Activity: 122

Merit: 10

Quote from: yusyus on September 20, 2016, 10:04:45 AM

Evil-Knievel,
have your team Twitter account for Elastic? to track news about XEL development. tnx

there is a reddit page r/XEL

Evil-Knievel

legendary

Activity: 1260

Merit: 1168

Quote from: yusyus on September 20, 2016, 10:04:45 AM

Evil-Knievel,
have your team Twitter account for Elastic? to track news about XEL development. tnx

Actually, I think everyone is doing his own stuff here!

One is doing the client, one is doing the website, another one is making a block explorer. We all ("we all is elastic itself, as people come and people go") have the idea behind elastic in mind, and transform our own interpretation of it into code Wink

This means that there is no central authority telling us what to do, and there is also no central authority which gathers weekly status reports to post them on a PR platform.

But this is the fun thing, about Elastic! You can do whatever you want as long as the community accepts it (because if the community does not accept it, it would just ignore it and substitute the specific part with something else)!
So if you feel the need of a twitter page, you can always make one and start collecting updates which you publish there Wink

There is nothing that would stop you from that!

yusyus

hero member

Activity: 495

Merit: 500

Evil-Knievel,
have your team Twitter account for Elastic? to track news about XEL development. tnx

Evil-Knievel

legendary

Activity: 1260

Merit: 1168

hagie, this feature is not yet developed. ~~Doing~~ Starting that today, but yes ... you will see your own miner there.

hagie

hero member

Activity: 792

Merit: 501

Quote from: Evil-Knievel on September 20, 2016, 05:59:00 AM

Fed up with the infinitely long list of work?
Then use the new pagination feature Grin

Should I see my own miner in the "minign overview" ? In my case it's empty.

Regards

Evil-Knievel

legendary

Activity: 1260

Merit: 1168

In the difficulty plot above, by the way, you see the problem of the current difficulty retargeting approach -> it's oscillating!
We have to fix that!

Evil-Knievel

legendary

Activity: 1260

Merit: 1168

Fed up with the infinitely long list of work?
Then use the new pagination feature Grin

Evil-Knievel

legendary

Activity: 1260

Merit: 1168

Quote from: unvoid on September 19, 2016, 01:42:20 PM

Stopping at 3319 block.

Fixed by blacklisting a number of hard coded tx's on the testnet.

Code:

boolean isDuplicate(Transaction transaction, Map> duplicates) {
				
				// Whitelist few specific, broken TX on the testnet (TODO, FIXME, TOREMOVE)
				List valid = new ArrayList();
				valid.add(Convert.parseUnsignedLong("7598634667181063828"));
				valid.add(Convert.parseUnsignedLong("2649304177138953307"));
				valid.add(Convert.parseUnsignedLong("10947343728076427070"));
				valid.add(Convert.parseUnsignedLong("16510862602090746736"));
				valid.add(Convert.parseUnsignedLong("12295851544522530488"));
				valid.add(Convert.parseUnsignedLong("4910487200763544778"));
				if(valid.contains(transaction.getId()))
					return false;
}

They are a relict from the time when there was no semantic "duplicate tx" check in place (a check that finds duplicate work cancellations with different tx ids for example).
The hard coded fix should avoid the crash ... we have to take this whitelist out when we restart the net some time in the future.

unvoid

hero member

Activity: 535

Merit: 500

After update (wait >10min) and del nxt_test_db can't download full blockchain.

Code:

2016-09-19 18:39:16 FINE: Got 1 confirmations
2016-09-19 18:39:16 INFO: Downloaded 443 blocks in 7 s, 187 per s, 0 min left
2016-09-19 18:39:16 INFO: Finished blockchain download
2016-09-19 18:39:16 FINE: Cannot find any archive peers
2016-09-19 18:39:16 FINE: Remaining 12 pruned transactions
2016-09-19 18:39:19 INFO: Blockchain download in progress
2016-09-19 18:39:20 FINE: Blacklisting 52.28.123.208 because of: nxt.BlockchainProcessor$TransactionNotAcceptedException: Transaction is a duplicate, transaction 7598634667181063828 {"senderPublicKey":"964be53db0cc61dd465fa765b03651c1bb06c7ce6b738be739ee1f143ea1910f","attachment":{"version.WorkIdentifierCancellationRequest":1,"id":"190164203855439272"},"subtype":5,"amountNQT":0,"signature":"ac9f26ac4832382c25bec0605683220b1852d0ff423018eb36a3e23daa30f30c8f407cafc0075d5579242358c8e044376d094db715699feb5d4fd6d4044bed49","feeNQT":100000000,"ecBlockHeight":0,"type":3,"deadline":1440,"version":1,"timestamp":88850158,"ecBlockId":"445516706271790606"}
nxt.BlockchainProcessor$TransactionNotAcceptedException: Transaction is a duplicate, transaction 7598634667181063828 {"senderPublicKey":"964be53db0cc61dd465fa765b03651c1bb06c7ce6b738be739ee1f143ea1910f","attachment":{"version.WorkIdentifierCancellationRequest":1,"id":"190164203855439272"},"subtype":5,"amountNQT":0,"signature":"ac9f26ac4832382c25bec0605683220b1852d0ff423018eb36a3e23daa30f30c8f407cafc0075d5579242358c8e044376d094db715699feb5d4fd6d4044bed49","feeNQT":100000000,"ecBlockHeight":0,"type":3,"deadline":1440,"version":1,"timestamp":88850158,"ecBlockId":"445516706271790606"}
        at nxt.BlockchainProcessorImpl.validateTransactions(BlockchainProcessorImpl.java:1443)
        at nxt.BlockchainProcessorImpl.pushBlock(BlockchainProcessorImpl.java:1329)
        at nxt.BlockchainProcessorImpl.access$1200(BlockchainProcessorImpl.java:38)
        at nxt.BlockchainProcessorImpl$1.downloadBlockchain(BlockchainProcessorImpl.java:550)
        at nxt.BlockchainProcessorImpl$1.downloadPeer(BlockchainProcessorImpl.java:270)
        at nxt.BlockchainProcessorImpl$1.run(BlockchainProcessorImpl.java:175)
        at java.util.concurrent.Executors$RunnableAdapter.call(Executors.java:511)
        at java.util.concurrent.FutureTask.runAndReset(FutureTask.java:308)
        at java.util.concurrent.ScheduledThreadPoolExecutor$ScheduledFutureTask.access$301(ScheduledThreadPoolExecutor.java:180)
        at java.util.concurrent.ScheduledThreadPoolExecutor$ScheduledFutureTask.run(ScheduledThreadPoolExecutor.java:294)
        at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1142)
        at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:617)
        at java.lang.Thread.run(Thread.java:745)
2016-09-19 18:39:20 FINE: Will process a fork of 718 blocks, mine is 0
2016-09-19 18:39:20 FINE: Rollback from block 7694898814333207672 at height 3319 to 7694898814333207672 at 3319
2016-09-19 18:39:20 FINE: Didn't accept any blocks, pushing back my previous blocks
2016-09-19 18:39:20 INFO: Finished blockchain download
2016-09-19 18:39:42 FINE: 6 block generators found
2016-09-19 18:39:48 INFO: Blockchain download in progress
2016-09-19 18:39:49 FINE: Blacklisting 108.61.177.169 because of: nxt.BlockchainProcessor$TransactionNotAcceptedException: Transaction is a duplicate, transaction 7598634667181063828 {"senderPublicKey":"964be53db0cc61dd465fa765b03651c1bb06c7ce6b738be739ee1f143ea1910f","attachment":{"version.WorkIdentifierCancellationRequest":1,"id":"190164203855439272"},"subtype":5,"amountNQT":0,"signature":"ac9f26ac4832382c25bec0605683220b1852d0ff423018eb36a3e23daa30f30c8f407cafc0075d5579242358c8e044376d094db715699feb5d4fd6d4044bed49","feeNQT":100000000,"ecBlockHeight":0,"type":3,"deadline":1440,"version":1,"timestamp":88850158,"ecBlockId":"445516706271790606"}
nxt.BlockchainProcessor$TransactionNotAcceptedException: Transaction is a duplicate, transaction 7598634667181063828 {"senderPublicKey":"964be53db0cc61dd465fa765b03651c1bb06c7ce6b738be739ee1f143ea1910f","attachment":{"version.WorkIdentifierCancellationRequest":1,"id":"190164203855439272"},"subtype":5,"amountNQT":0,"signature":"ac9f26ac4832382c25bec0605683220b1852d0ff423018eb36a3e23daa30f30c8f407cafc0075d5579242358c8e044376d094db715699feb5d4fd6d4044bed49","feeNQT":100000000,"ecBlockHeight":0,"type":3,"deadline":1440,"version":1,"timestamp":88850158,"ecBlockId":"445516706271790606"}
        at nxt.BlockchainProcessorImpl.validateTransactions(BlockchainProcessorImpl.java:1443)
        at nxt.BlockchainProcessorImpl.pushBlock(BlockchainProcessorImpl.java:1329)
        at nxt.BlockchainProcessorImpl.access$1200(BlockchainProcessorImpl.java:38)
        at nxt.BlockchainProcessorImpl$1.downloadBlockchain(BlockchainProcessorImpl.java:550)
        at nxt.BlockchainProcessorImpl$1.downloadPeer(BlockchainProcessorImpl.java:270)
        at nxt.BlockchainProcessorImpl$1.run(BlockchainProcessorImpl.java:175)
        at java.util.concurrent.Executors$RunnableAdapter.call(Executors.java:511)
        at java.util.concurrent.FutureTask.runAndReset(FutureTask.java:308)
        at java.util.concurrent.ScheduledThreadPoolExecutor$ScheduledFutureTask.access$301(ScheduledThreadPoolExecutor.java:180)
        at java.util.concurrent.ScheduledThreadPoolExecutor$ScheduledFutureTask.run(ScheduledThreadPoolExecutor.java:294)
        at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1142)
        at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:617)
        at java.lang.Thread.run(Thread.java:745)
2016-09-19 18:39:49 FINE: Will process a fork of 718 blocks, mine is 0
2016-09-19 18:39:49 FINE: Rollback from block 7694898814333207672 at height 3319 to 7694898814333207672 at 3319
2016-09-19 18:39:49 FINE: Didn't accept any blocks, pushing back my previous blocks
2016-09-19 18:39:49 INFO: Finished blockchain download
2016-09-19 18:39:57 FINE: Unblacklisting 108.61.177.169
2016-09-19 18:39:57 FINE: Unblacklisting 52.28.123.208
2016-09-19 18:39:57 FINE: Unblacklisting 52.57.31.137
2016-09-19 18:40:01 FINE: Accepted new transaction 16121508601869408022

Stopping at 3319 block.

hagie

hero member

Activity: 792

Merit: 501

Quote from: Evil-Knievel on September 19, 2016, 10:11:43 AM

Bump to Version 0.3.5

A thread safety issue was fixed, where the VM got crippled when two work packages were verified at the same time.
This occasionally caused to become blacklisted by others.

Fix: https://github.com/OrdinaryDude/elastic-core/commit/3a2e2e02c14c85fdae5e0486301f6e12fdef22cf

Updated my public accessible node https://elastic.cryptnodes.site/

regards

Evil-Knievel

legendary

Activity: 1260

Merit: 1168

Bump to Version 0.3.5

A thread safety issue was fixed, where the VM got crippled when two work packages were verified at the same time.
This occasionally caused to become blacklisted by others.

Fix: https://github.com/OrdinaryDude/elastic-core/commit/3a2e2e02c14c85fdae5e0486301f6e12fdef22cf

tomkat

hero member

Activity: 1022

Merit: 507

Quote from: hagie on September 19, 2016, 05:31:07 AM

Quote from: tomkat on September 19, 2016, 04:57:46 AM

What is actually "Regular Bitcoin Signature" in redeem function?

This will be the way you can redeem your XEL tokens from your donation by using the private key of the address you send the donation from.

With this private key you could sign something.

This is as far I understand it ..

regards

Yes, it could be private key, but why is it called "Regular Bitcoin Signature" and not just "BTC Private Key" or something similar?

hagie

hero member

Activity: 792

Merit: 501

Quote from: tomkat on September 19, 2016, 04:57:46 AM

What is actually "Regular Bitcoin Signature" in redeem function?

This will be the way you can redeem your XEL tokens from your donation by using the private key of the address you send the donation from.

With this private key you could sign something.

This is as far I understand it ..

regards

Topic: [ANN][XEL] Elastic Project - The Decentralized Supercomputer - page 250. (Read 450524 times)