I just noticed in the mempool there are 8000ish pending transactions, mostly with 48 outputs…
Is the spam attack back on? Interestingly the outputs are to transparent addresses
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Will it be people or companies starting purchases, taking advantage of the discounted value of Zcash?
No they’re just tx’s with lots of outputs splitting small amounts of ZEC to lots of different addresses
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Yes, the unpaid action attack as it existed a few months back has started again last week.
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Yes it’s the spam attack again. Note however that ZIP-317 is preventing those from flooding blocks themselves. I think both zcashd and zebrad will remove the “unpaid action limit” in the next release which will prevent these from being mined at all.
Fun fact: I noticed those addresses are the ones corresponding to the private keys with value 1, 2, 3 and so on. Theoretically anyone could spend them, but it wouldn’t be worth it since the fee would be larger than the amount.
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so they are basically burning ZEC?
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pretty much, yes
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I apologize if this has been addressed before, but why even allow spam transactions into the mempool? Can the protocol rules stop them from being broadcast in the first place?
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Yes, zip 317 will prevent that, and it’s been in the protocol for a long time.
This, going on now, is because of the unpaid action limit, which is in place to allow for wallets to upgrade to conform to the new transaction fee rules.
Once it’s removed, any transaction that pays a fee short of the minimum required, per its action consumption, will be rejected.
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At first we couldn’t simply block them, because that would also block legitimate transactions.
ZIP-317 was introduced which changed the fee to be proportional to the number of inputs/outputs of the transaction. However, we still needed to allow some transactions to go through even if they haven’t paid the proper fee, because it would take some time for wallets to implement the new fee. This prevented spam in the blocks, but still allows spam in the mempool.
Now they have, and in the next release of zcashd and zebrad they should all get blocked.
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What I don’t understand is why nearly all blocks being mined have only 2-5 txs in them. I’ve watched many, many txs with high-paying fees sit at the “top” of the mempool (when sorted by fee) without getting mined – often for so long that the txs just timeout and get dropped.
Anyone know why that might be? It makes the de facto throughput rate of zcash something silly like 0.05 txs/sec. For me, personally, it has made zcash maddeningly frustrating to use.
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The fee paid is relative to the actions that go into the transaction. It could be an extremely high fee but still not pay enough if it has many, many inputs or outputs. 
I just made a test transaction to myself in Ywallet with autofee and it was mined within 2 blocks (I recorded it if you really gotta see, txs that pay the proper fee nowadays are almost always commited, faiap, instantly). The mempool goes FIFO and technically only Ywallet and zashi (and zcashd internal wallet I suppose) support proper fee payment so if these transactions are being made with any other wallet, then it’s possible/likely that they will not get mined in the current mempool state or going forward after the unpaid action limit is removed.
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ZIP-317 specifies what the proper fee should be for a transaction, and it’s proportional to the number of inputs and outputs. These spam transactions don’t pay the proper fee. They are still allowed but a small number of them get to be mined (currently one per block). Txs with proper fees will have higher priority so they won’t take long to get mined. 2-5 txs is the “regular” flow of transactions without the spam, so that should not be the issue.
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i officialy propose to create a backdoor in the Zcash code to find the spammer
Oh, that makes a lot of sense, thank you. I wasn’t using Ywallet or Zashi. I’ll try switching to one of them.
UPDATE: I installed Zashi and it looks like it only supports Unified addresses without the ability to control – or even see – what the unified address is encoding ( e.g., whether or not it includes a transparent address) and transparent addresses. So that wallet is a non-starter for me. I’m genuinely surprised to see that from an ECC product, but I suppose they just leaned a little too heavily towards simplifying the experience for the user as much as possible.
I also installed Ywallet and am blown away! It’s amazing. I have all the control I need over what addresses I share, which means I can finally feel safe using the Orchard pool <3. Total game changer. Ty for the recc.
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