I'm afraid we have a fairly major problem with the blockchain atm, and in a way its a lovely example of the problem with PoS coins:

PoS staking was working fine until around the 9th Nov, with blocks being created around the target rate of 1 per minute, but then it got slower and slower until it was approaching 1 per day. This was caused by a combination of not enough SPARK actively staking on the network, and a relatively high minimum PoS difficulty. After waiting to see if the problem would sort itself out it appeared necessary to update the wallet code to address the problem - hence ver1.3 was released early on the 22nd.

Approx. 21:00 on the 22nd a large SPARK wallet (possibly as much as 300k) reconnected to the network - unfortunately before it resynced with the current blockchain it had already started generating its own PoS blocks and because its so much bigger than the rest of the wallets staking for the last two weeks that chain took precedence. Bittrex monitor things like this, I expect some alert went off and that's why we have the post from Richiela at 21:30 about the 55 block rollback.

Two problems now exist:

1) That big wallet wasnt updated to v1.3, so wallets which are updated to v1.3 are rejecting its blocks because they use the wrong difficulty calculation. Not really a major problem because the network weight (amount of staking SPARK) in 1.3 wallets is tiny compared to the 1.2 version, so we could downgrade again without much trouble.

2) The 55 block rollback means that transactions included in the lost blocks no longer exist, so exchange ledgers will no longer balance - deposits and withdrawals will have been cancelled. People have a habit of not resending coins to the exchange when that sort of thing happens, so they end up out of pocket.


The only solution I can think of currently is to enforce a rollback - if I can find a copy of the correct blockchain as close to block 24623 (where it was before that large wallet appeared) I can produce a v1.3.1 which includes checkpoints to enforce that blockchain as the correct one. Edschroedinger has sent me a copy which he thinks is pretty close to that, I havent had a chance to check it yet. Its definitely a hard fork update (again) though, so I can't guarantee that Bittrex or Bter will want to go through all the hassle of sorting it out.

Little bit of good news, my main node has staked block 24631 on the ver1.3 wallet, so the new diff calc is working.

I've had a look through the daemon log on my node and I think I can see what has happened, but I cant offer much of a solution atm.

Problem starts with this node appearing on the network, at around 21:00GMT:

trying connection 46.105.118.15:16665 lastseen=365747.2hrs
connected 46.105.118.15:16665
send version message: version 70000, blocks=24624, us=81.107.175.74:16665, them=46.105.118.15:16665, peer=46.105.118.15:16665
Added time data, samples 15, offset +1 (+0 minutes)
nTimeOffset = -7  (+0 minutes)
Moving 46.105.118.15:16665 to tried
receive version message: version 70000, blocks=24568, us=81.107.175.74:63435, them=46.105.118.15:16665, peer=46.105.118.15:16665


At that point it is 56 blocks behind the rest of the network, but rather than get back in sync it starts broadcasting its own chain, which has a far higher trust than the existing one so it gets accepted as valid and replaces the existing chain.

For that to happen the node in question, or nodes connected to it and not the rest of the network, must be staking a much larger number of SPARK than the rest of the network put together. I've had a look through a few of the blocks produced and each appears to generate a stake interest of around 9SPARK, with an output of 1038SPARK to a wallet - I believe this is because a large wallet will split the coins into smaller chunks for staking. The outputs I checked all went to the same address:

SUpCAdvbrsmm99EPxr7ob8DWuLK2fT9Zpk

One other thing I can say is that the node in question hadnt updated to v1.3, as my node started rejecting its blocks after 24630 as they were using the new diff calculation. My node then started blocking it and other nodes pre1.3 as it assumed they were "misbehaving", so I cant tell whether the "problem node" is still on the network or not. Only other info is that the problem node IP address traces back to OVH server hosting in France, so its probably not a domestic holder, more likely a pool or exchange.


There weren't a huge number of txes in the 55 blocks lost, but that doesnt really matter, unless Bittrex have another way of seeing their withdrawals/deposits they cant be sure of making their books balance, which isnt a good thing for an exchange. I'm now looking to see if I have have a copy of the "old" blockchain backed up anywhere, if so it might be possible to do something with checkpoints and another wallet update....

You need a bunch of QT dlls - download the spark-qt1.2 release first, that has the core QT files you need with it, then replace the spark-qt.exe with the v1.3 download.

I have sent messages to BITTREX and BTER asking them to update their wallets - if you are waiting for a deposit or withdrawal to confirm with them then once they are updated things should get back to normal.

Currently I am taking the generous view that the slow network is the reason why the "donation wallet" is still empty, no doubt plenty of you SPARK owners have sent donations but the txes are still waiting to be confirmed ;0

I honestly have less than 2k SPARK, I do this mainly because I find it interesting but updating and compiling a new wallet release is a time consuming process so motivation is important! Moral support is most appreciated but financial rewards are also very encouraging so feel free to show your support by sending some SPARK to Sg2dujC3jMa9j1ff41sjAZRV4mZkjwgN6G

Thanks!

Greetings SPARKers! I have just completed the upload of SPARK v1.3 - this is a MANDATORY upgrade!!

I have made several changes to address the slow block production problem that is delaying txes and making the coin nearly unusable:

• Reduced the minimum PoS difficulty level allowed
• Reduced the number of blocks required before moved SPARK can start staking again
• Changed the difficulty retargeting algorithm to respond more efficiently
• Also replaced the DNS seed node so new users should find it easier to connect their wallet

The algo change is set to take effect at block 24630, if you have not updated by then your wallet will start rejecting new blocks.

The new source code and compiled Windows release are available at https://github.com/RentaMouse/Spark/releases/tag/v1.3.0

Rather than package the complete install again this is just the updated Spark-qt.exe - download it and replace the existing exe file in your Spark folder. To be on the safe side this is a good opportunity to make a backup of your SPARK wallet.dat file.

I have also updated my Windows QT compiler so hopefully this release will be more stable than the original version. I'm afraid there are still a lot of (mainly cosmetic) features in the GUI wallet which do not function, Most of them, e.g. the market data, are coded to use the getspark.com web server which the original dev took offline when he quit and I dont see them as a priority to fix. Once we get the network stable I have some ideas for making SPARK useful, more on that to come.

Noone is being scammed, block production is just too slow currently so transactions take too long to confirm. I will release an updated client with fix as soon as I can, in the meantime the more people with SPARK staking on the network the more blocks will be produced.

Ok, I've been keeping an eye on the blockchain and the min PoS difficulty will have to be reduced so we can have a reasonable block production rate for staking, transactions etc. Its not a difficult change to make so new wallet version should be ready soon.

Shouldnt have been anything extra, as long as your wallet is getting peer connections and receiving new blocks it should be able to send transactions on the network. If you are using the Windows wallet you should be able to go to the "transactions" page and right click on your sending tx, then copy the tx id. The tx lookup on the Block Explorer page isnt great but it should come back with some info if the tx is on the blockchain, if it says "fail" then for some reason the tx wasnt broadcast.

If it did fail then one possibility is that it spent too long in the mempool without being included in a block, the default is usually 24hrs (I havent checked if that has been modified in SPARK but I doubt it), after which it would be flushed. However if that did happen the coins should be returned to your wallet so you can try sending again...

Something must have gone wrong with your transaction I'm afraid, we've had about 40 blocks in the last 48hrs - still a lot lower than it should be, but txes only need 10 blocks to confirm so your SPARK should have reached BTER. If you find your tx id you can use the "Block Explorer" in the Windows wallet to check whether it is in the blockchain. Otherwise it may be that your wallet is out of sync - at the time of writing we are on block 24614

There was a post from Supernova pool a couple of days ago saying they were going to close their wallet.

Problem with the staking is still apparent - the difficulty cannot drop any more than the current 0.000244 - if you have a small number of coins staking then it may take several days for them to build up enough stake weight to get a block. You dont lose out on any interest but its causing a problem still because the low block count means it takes a long time for transactions to completely confirm (needs 10 blocks).

If block production isnt back to normal in the next day or two I will look at releasing another wallet update to address the problem.

Ok, instead of doing the stuff I'd planned to do for the last 2-3 hours I've ended up investigating this slow blocks issue and have come to some conclusions:

First of all the problem is that there aren't enough coins staking over the last 24hrs - prior to that it was ok so I assume there are sufficient coins in circulation, its just a lot of them have either staked or been moved, so they are stuck in "limbo" currently. Until a few more blocks are confirmed (txes need 10 blocks to confirm) they will remain in limbo.

The problem is made worse because SPARK has a hard coded minimum PoS difficulty that is relatively high, making it harder for stakes with a low coin age (number of coins * their age) to hit an acceptable block. This can be adjusted but it will require a hard fork.

I suspect this problem is linked to Bittrex re-enabling their wallet so a lot of coins which were staking are now being moved around, if that is the case the problem should fix itself as blocks are slowly found and more txes confirm so the coins start staking again.

Unfortunately neither Ed or I have many SPARK which doesnt help, of course donations are most helpful at motivating us to do more work - even if they will take a while to arrive currently feel free to send to Sg2dujC3jMa9j1ff41sjAZRV4mZkjwgN6G - thanks!

I'm investigating why block production is slow currently, so far I'm not seeing any errors, just the network saying that there arent many coins staking.

Has anyone had trouble with their coins not staking (stake rewards not appearing, it will take a while for them to be fully confirmed at current block rate)?

Give us a clue - have you downloaded the v1.2 release from https://github.com/RentaMouse/Spark/releases ?

If you have that, did you follow the bit about using the Spark.conf file to make sure you have the new nodes added?

If your wallet gets to block 14,400 and then stops syncing, close it and reopen it a few minutes later, it should then sync the rest of the blocks.

Sounds like its loading but not liking your config file - you may find that disabling your network connection (unplug the cable if you prefer) whilst the wallet starts, and then re-enabling the network afterwards will be enough.

From my testing it seems to be something with IPv6 it doesn't like, another thing to try is enabling/disabling IPv6 in your network settings.

Brief update for you all:

The v1.2 release of the Linux and Windows wallets seems to be working reliably for those who have upgraded, the network is stable and PoS staking is working.

We have a good idea now of how to implement the "superblock" to raise funds to clear the shortfall on the exchanges, but its going to take a bit of time to code and more importantly test - we dont want to cause another fork!

Website and block explorer will be reinstated too, dont forget that the Windows wallet does have its own block explorer built in!

If I'm online I will try and remain logged in at the #sparkcoin IRC channel, will try and answer technical questions etc   

We are talking to the exchanges about how to get deposits/withdrawals working again; Bittrex, Bter and C-Cex have all said they are willing to work with us but because of the fork their books are unbalanced by around 50K SPARK in total. Ideally we might raise that amount from donations but we are also investigating the possibility of a one off "reboot block" with a 50k reward to fund it.

This coin appeared to get off to a good start, would be a shame to waste that and see everyone who invested hashpower/BTC lose out - hopefully the SPARK community will continue to support this effort. Support doesnt just have to be financial, time and skills are valuable too if anyone has some they can contribute!

Ah, I love the effort that goes into posting comments like this, surely if you had bothered to read much of the last few pages you might have come up with something more accurate like "waiting to see if this coin can recover from the network fork and exchange trading suspension before I buy"......

For those are interested, will see what the feedback is like now people have a Windows wallet to get back on the blockchain with, and will do something about setting up a new thread since we have no control over this one. I'm not a fan of moderated threads, but I know what the trolling can be like on BTCtalk (usually a sign that a coin is making progress!), so if anyone has a strong opinion pls state.

And of course, any volunteers to join this project are most welcome!

For anyone with some SPARK I've managed to release a Windows version of the fixed wallet now, you can download it from Github at https://github.com/RentaMouse/Spark/releases/tag/v1.2.0

IPOminer can confirm but I believe the pool was on the "correct" fork all along so no miners should have lost out, it seems that some of the exchanges and maybe one pool who joined after launch received a different version of the wallet to the launch release and that contributed to the network fork.