Requesting Testnet4 tBTC - page 2. | Bitcointalksearch.org

BlackHatCoiner

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Activity: 1512

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Farewell, Leo

Quote from: LoyceV on August 31, 2024, 10:12:08 AM

Here, it tops off at 400.0% CPU (so 4 cores).

In Linux Mint, CPU usage goes up to 100%. If you have 12 cores, and the program uses 8.3% of the CPU, it means it uses 1 core. If it uses 33%, it means it uses 4 cores. So, it perhaps depends on the architecture of the OS. (I guess that the fact that it's using the same number of cores in both of us, is a good sign.)

Quote from: LoyceV on August 31, 2024, 10:12:08 AM

I'm not sure how useful it is though: sometimes different threads find the same block, and sometimes they find different blocks.

That's a problem, indeed. You can avoid it by using different Bitcoin address in each thread, but it makes everything more complicated for no reason. An extra nonce field in generatetoaddress would solve this problem.

Edit: Just solved the same block four times Cheesy

Code:

$ ./exec2
Num of available threads: 12
thread 0 is running...
thread 1 is running...
thread 2 is running...
thread 3 is running...
thread 4 is running...
thread 5 is running...
thread 6 is running...
thread 7 is running...
thread 8 is running...
thread 9 is running...
thread 10 is running...
thread 11 is running...
[
  "00000000f095255ea490763a99f02b2adfae1f2ca4df708db02fa5a1777b4217"
]
[
  "00000000f095255ea490763a99f02b2adfae1f2ca4df708db02fa5a1777b4217"
]
[
  "00000000f095255ea490763a99f02b2adfae1f2ca4df708db02fa5a1777b4217"
]
[
  "00000000f095255ea490763a99f02b2adfae1f2ca4df708db02fa5a1777b4217"
]

LoyceV

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Thick-Skinned Gang Leader and Golden Feather 2021

Quote from: BlackHatCoiner on August 31, 2024, 08:43:55 AM

Is it possible to run bitcoin-cli generatetoaddress in multiple threads? I wrote a C program which calls 12 forks, each having its own thread, but it doesn't get all the CPU power. It's strange; it only takes 33% of the CPU. (My total threads are 12.)

Here, it tops off at 400.0% CPU (so 4 cores). I'm not sure how useful it is though: sometimes different threads find the same block, and sometimes they find different blocks.

BlackHatCoiner

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Activity: 1512

Merit: 7340

Farewell, Leo

Is it possible to run bitcoin-cli generatetoaddress in multiple threads? I wrote a C program which calls 12 forks, each having its own thread, but it doesn't get all the CPU power. It's strange; it only takes 33% of the CPU. (My total threads are 12.)

Code:

#include
#include
#include
#include
#include
#include

void* runner(void* param);

int main(int argc, char** argv)
{
int i, num_threads = sysconf(_SC_NPROCESSORS_ONLN);
printf("Num of available threads: %d\n", num_threads);

pthread_t* threads = malloc(num_threads * sizeof(pthread_t));
int* thread_ids = malloc(num_threads * sizeof(int));

for(i = 0; i < num_threads; i++){
thread_ids[i] = i;
if(pthread_create(&threads[i], NULL, runner, &thread_ids[i]) != 0){
perror("pthread_create failed");
free(threads);
free(thread_ids);
}

}

for(i = 0; i < num_threads; i++){
pthread_join(threads[i], NULL);
}

free(threads);
free(thread_ids);

printf("All threads have finished execution\n");

return 0;
}

void* runner(void* param)
{

printf("thread %d is running...\n", *(int*)param);
pid_t pid = fork();
if (pid == 0) {
// In child process: execute the command
execl("./bitcoin-cli", "bitcoin-cli", "--testnet4", "generatetoaddress", "1", "

", "10000000", NULL);
// If execl fails
perror("execl failed");
exit(1);
} else if (pid > 0) {
// In parent process: wait for the child process to finish
int status;
waitpid(pid, &status, 0);
} else {
perror("fork failed");
}

return NULL;
}

Everything seems to be executing properly:

Code:

$ ./exec2
Num of available threads: 12
thread 0 is running...
thread 1 is running...
thread 2 is running...
thread 3 is running...
thread 4 is running...
thread 5 is running...
thread 6 is running...
thread 7 is running...
thread 9 is running...
thread 8 is running...
thread 11 is running...
thread 10 is running...
[
]
[
]
[
]
[
]
[
]
[
]
[
]
[
]
[
]
[
]
[
]
[
]
All threads have finished execution

I know that there is already some CPU mining software out there for multiple-thread mining, but I want to write my own. It's also made for testing purposes, since we're in testnet.

garlonicon

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Pawns are the soul of chess

Quote

I don't know why there's ] and | in front.

Because of block height, which is mandatory, since BIP-34. And because mempool.space decodes block height as ASCII, it is what it is.

Also note, that there are more mining pools, marked as "Unknown". The list of tags is probably centrally managed by mempool.space, so you can ask them about it. Or try to format it in the same way as "wiz" did.

LoyceV

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Quote from: garlonicon on August 30, 2024, 03:18:50 AM

Code:

coinbaseTx.vin[0].scriptSig = CScript() << nHeight << ParseHex("4c6f79636556207761732068657265");

After "nHeight", you can add any Script in "src/node/miner.cpp", recompile it, and then restart your node. But of course, if you don't want to touch the client, then there are other options. Usually, some mining client has something called "coinbaseaux" or similar. For "LoyceV was here", it would be "4c6f79636556207761732068657265" (sometimes you have to specify it in hex, sometimes not, probably you should try it in regtest first, to be sure).

Thanks, that (kinda) worked. It still shows the Miner as unknown, but it has a Coinbase tag:
Image loading...

I don't know why there's ] and | in front.

garlonicon

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Activity: 821

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Pawns are the soul of chess

Quote

how do I get one of those cute little Miner tags "LoyceV was here"

Do you want to get only some message, or something special? Usually, I just change the code, for example:

Code:

// Create coinbase transaction.
CMutableTransaction coinbaseTx;
coinbaseTx.vin.resize(1);
coinbaseTx.vin[0].prevout.SetNull();
CAmount nFeesWithSubsidy = nFees + GetBlockSubsidy(nHeight, chainparams.GetConsensus());
if(nFeesWithSubsidy<=10*1000*COIN)
{
   coinbaseTx.vout.resize(1);
   coinbaseTx.vout[0].scriptPubKey = scriptPubKeyIn;
   coinbaseTx.vout[0].nValue = nFeesWithSubsidy;
}
else
{
   coinbaseTx.vout.resize(1);
   coinbaseTx.vout[0].scriptPubKey = scriptPubKeyIn;
   coinbaseTx.vout[0].nValue = 10*1000*COIN;
}
coinbaseTx.vin[0].scriptSig = CScript() << nHeight << ParseHex("4c6f79636556207761732068657265");

After "nHeight", you can add any Script in "src/node/miner.cpp", recompile it, and then restart your node. But of course, if you don't want to touch the client, then there are other options. Usually, some mining client has something called "coinbaseaux" or similar. For "LoyceV was here", it would be "4c6f79636556207761732068657265" (sometimes you have to specify it in hex, sometimes not, probably you should try it in regtest first, to be sure).

Edit: Let's see: https://mempool.space/testnet/tx/5e739e2a69fe22f8b3f7536c35cbb710ddb725e5660f3996e902ee6eeb36c21a

LoyceV

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Quote from: vjudeu on August 30, 2024, 01:35:45 AM

Quote

Invalid parameter --testnet4

Which version? Both master and v28.0 should have it.

I'm not even sure anymore. I now used https://github.com/bitcoin/bitcoin/tree/28.x and that works. I have enough testnet4 coins to give them away until the end of days Cheesy

One more question: how do I get one of those cute little Miner tags "LoyceV was here" (just like Portland.HODL)? That would be a cool thing to have before I turn this off again

I tried Googling it, but couldn't find it.

vjudeu

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Activity: 813

Merit: 1944

Quote

Invalid parameter --testnet4

Which version? Both master and v28.0 should have it.

Code:

$ ./bitcoind --version
Bitcoin Core version v28.0.0rc1
Copyright (C) 2009-2024 The Bitcoin Core developers

Please contribute if you find Bitcoin Core useful. Visit
for further information about the software.
The source code is available from .

This is experimental software.
Distributed under the MIT software license, see the accompanying file COPYING
or

LoyceV

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Thick-Skinned Gang Leader and Golden Feather 2021

Quote from: garlonicon on August 29, 2024, 01:23:09 PM

Or: you can also use https://github.com/bitcoin/bitcoin/tree/28.x because this is what you can get, if you download release candidate for v28. But usually I just stick with the master.

I'll try this next, thanks.

Quote

Edit:

Quote

Code:

./bitcoind --testnet4 -prune=25000

A single dash in -testnet4, not --testnet4.

Both work. Bitcoin Core isn't so picky. That's why I got sloppy with the dashes.

garlonicon

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Pawns are the soul of chess

~~Maybe the author changed that branch in the meantime.~~ Now, you can just clone the official code from https://github.com/bitcoin/bitcoin/ from the master branch, because things are already merged.

Also:

Quote

This branch is 360 commits behind bitcoin/bitcoin:master.

So, I guess using official code is better now. At the time of writing, it was not yet merged, so there was no other way.

Or: you can also use https://github.com/bitcoin/bitcoin/tree/28.x because this is what you can get, if you download release candidate for v28. But usually I just stick with the master.

Edit:

Quote

Code:

./bitcoind --testnet4 -prune=25000

A single dash in -testnet4, not --testnet4.

LoyceV

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Quote from: vjudeu on August 29, 2024, 08:01:57 AM

Quote

If this is ELI5, I may need ELI4....

If you can get a single block, after the Genesis Block, then it means, that you have enough computing power, to mine on testnet4.

Quote

Edit "src/chain.h" and "src/node/miner.cpp" exactly as I presented on forum.

Those code changes are simple:

1. Go to "src/chain.h".
2. CTRL+F "static constexpr int64_t MAX_FUTURE_BLOCK_TIME = 2 * 60 * 60;"
3. Replace it with: "static constexpr int64_t MAX_FUTURE_BLOCK_TIME = 20 * 60 * 60;"
4. Save changes.

5. Go to "src/node/miner.cpp".
6. CTRL+F "int64_t nNewTime{std::max(pindexPrev->GetMedianTimePast() + 1, TicksSinceEpoch(NodeClock::now()))};"
7. Replace it with: "int64_t nNewTime{std::max(pindexPrev->GetMedianTimePast() + 1, pindexPrev->GetBlockTime() + consensusParams.nPowTargetSpacing*2 + 1)};".
8. Save changes.

Thanks, I got this far. But after compiling, it doesn't seem to know "testnet4":

Code:

./bitcoind --testnet4 -prune=25000
Error: Error parsing command line arguments: Invalid parameter --testnet4

This was after I used https://github.com/fjahr/bitcoin/tree/2024-04-testnet-4-fix so not what I expected.

vjudeu

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Activity: 813

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Quote

If this is ELI5, I may need ELI4....

If you can get a single block, after the Genesis Block, then it means, that you have enough computing power, to mine on testnet4.

Quote

Edit "src/chain.h" and "src/node/miner.cpp" exactly as I presented on forum.

Those code changes are simple:

1. Go to "src/chain.h".
2. CTRL+F "static constexpr int64_t MAX_FUTURE_BLOCK_TIME = 2 * 60 * 60;"
3. Replace it with: "static constexpr int64_t MAX_FUTURE_BLOCK_TIME = 20 * 60 * 60;"
4. Save changes.

5. Go to "src/node/miner.cpp".
6. CTRL+F "int64_t nNewTime{std::max(pindexPrev->GetMedianTimePast() + 1, TicksSinceEpoch(NodeClock::now()))};"
7. Replace it with: "int64_t nNewTime{std::max(pindexPrev->GetMedianTimePast() + 1, pindexPrev->GetBlockTime() + consensusParams.nPowTargetSpacing*2 + 1)};".
8. Save changes.

As I said: you can do that, and recompile Bitcoin Core, then all "generateXYZ" commands will give you easier blocks. The alternative is to not touch Bitcoin Core at all, but then, you have to extract the whole block, save it somewhere, replace time and difficulty, and then pass your 80-byte header to your mining software. But for me, recompiling Bitcoin Core is easier.

Quote

Long time ago, when I started, I simply used "generatetoaddress" command manually, and modified my system clock, to set it 20 minutes after the last block.

This is another way, if you don't want to touch your source code. You can simply set your system clock 20 minutes into the future. But then:

1. You will get some warnings, that "your clock is different, than in other nodes".
2. It will work only for a single block. When you mine it, then you won't mine a second block on top of that, because you will need to move your time again, 20 more minutes forward, or you will be mining with the real difficulty.
3. If any other CPU miner will produce a block, then you will mine again with the real difficulty.
4. Your browser will tell you, that HTTPS connection is insecure, because your system time will be set differently.
5. Other programs, or even your Operating System, may try to update your time, and set it automatically, if you don't disable it.

So, by manually tweaking your system clock, and using unmodified Bitcoin Core, you can mine a block or two, but it quickly becomes tedious.

But of course, if you have nothing else, then you can start with that. If you change your system clock manually, and then restart Bitcoin Core, you should be able to mine a block on your CPU, if your block template will give you "1d00ffff".

LoyceV

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Quote from: vjudeu on August 05, 2024, 01:27:41 PM

If you can get it right, then you can mine blocks with the minimal difficulty, and we can go further. This simple exercise is what I started with, long time ago, when I was curious, how to mine blocks with Bitcoin Core.

This worked:

Code:

{
"hash": "0000000085550338d113b883f211c87c7aa3e045ba6e03bae855ea884d1a1be7",
"confirmations": 1,
"height": 1,
"version": 536870912,
"versionHex": "20000000",
"merkleroot": "20bb379fd28f090730ac2d207b92c6e95c69dfa48a8118577edb20e068c9a65d",
"time": 1724929784,
"mediantime": 1724929784,
"nonce": 157273468,
"bits": "1d00ffff",
"difficulty": 1,
"chainwork": "0000000000000000000000000000000000000000000000000000000200020002",
"nTx": 1,
"previousblockhash": "000000000933ea01ad0ee984209779baaec3ced90fa3f408719526f8d77f4943",
"strippedsize": 225,
"size": 225,
"weight": 900,
"tx": [
"20bb379fd28f090730ac2d207b92c6e95c69dfa48a8118577edb20e068c9a65d"
]
}

Quote from: garlonicon on August 05, 2024, 12:53:39 PM

3. Edit "src/chain.h" and "src/node/miner.cpp" exactly as I presented on forum.

If this is ELI5, I may need ELI4....

BlackHatCoiner

legendary

Activity: 1512

Merit: 7340

Farewell, Leo

I could swear that both these links sent me to the same transaction. SMF bug? ... Anyway, thanks, I'll try to mine a block and let you know.

vjudeu

hero member

Activity: 813

Merit: 1944

Quote from: garlonicon on June 13, 2024, 02:29:32 AM

Is it possible directly from Core with generatetoaddress?

Yes, if your Bitcoin Core implementation will always give you the block template, moved forward by 20 minutes.

Quote

And, is there mining software for testnet that is configurable with GPUs?

You have regular Bitcoin Core node. You can connect CPUs, GPUs, FPGAs, ASICs, whatever. The most difficult part is to get the block header, which has the minimal difficulty. For example, if you call "getblocktemplate", you should see this:

Code:

$ ./bitcoin-cli -testnet4 getblocktemplate '{"rules": ["segwit"]}'
{
"capabilities": [
"proposal"
],
"version": 536870912,
"rules": [
"csv",
"!segwit",
"taproot"
],
"vbavailable": {
},
"vbrequired": 0,
"previousblockhash": "00000000000000308df706a8736dfe78eee7cea416adc1dc5bfcf4bc11202f6c",
"transactions": [
{
"data": "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",
"txid": "ff162dc6fcf24922a43662e445f7a0ddaec61dece249f4e01364696802bd9aee",
"hash": "ecaba0fa0b919a167fbeee188ae394822e8e2e26d779df4c4132093fc7642797",
"depends": [
],
"fee": 605,
"sigops": 8,
"weight": 1390
},
{
"data": "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",
"txid": "fb743188fee53fb54e4a839a176e37d74209a5eaf0df20513e16005147a7c5a3",
"hash": "80e7071bac1b5ac08a8ddfe4c13dc29e0c1d7063a884de9703e51b28fb71ad9f",
"depends": [
],
"fee": 255,
"sigops": 6,
"weight": 848
},
{
"data": "02000000000101d4c733a3d78574af8a5f8242f036f0529b8cdf049504f532f3cb4376a53876950100000000fdffffff03f70100000000000022512010397b2d4a2d4a67d55ccaee88c0e8e92c7f38aeebf4ca0e40499962586309a9ec030000000000002251205ae432a8aa5e7aa98d47c74a28390db89edec262d4e2ca1f6b41704495c01d4bb28a070000000000225120d2912b91d0802aa584f4c8ff364f9bb2d5af103368fef4c61584b34f1f081f8b01407848bd0612823ee11f6153ac354f91238cf9c9db66a60a234fbf1f43d3749228e1a1475eae46f66cf5606f262be605383268fe608ab25cb7c0458684cba6149c00000000",
"txid": "9e5fd8b8a6d206db9117852e9fecb54a1792be229c09c004912e9f2d455d49b1",
"hash": "464504217e5bcd3ddce9d6db8adc1ac3f65af434cfc6e1094ae03e6420b9ced5",
"depends": [
],
"fee": 197,
"sigops": 0,
"weight": 788
},
{
"data": "02000000000101b1495d452d9f2e9104c0099c22be92174ab5ec9f2e851791db06d2a6b8d85f9e0000000000fdffffff014a01000000000000225120d2912b91d0802aa584f4c8ff364f9bb2d5af103368fef4c61584b34f1f081f8b03406bbe431da4a0931ee616f95c5f00d4ac4ed3828abd2b46c029a11ea5b2cc0ab1eae3bab0ee977409deaa1b598f5fdb5e4a4ec740b7cacc7960cf77fe139d6e0bab206a11672055d3ad2b612dc3372a7101f402816920842ce10c1aeeff3de093c72fac0063036f7264010118746578742f706c61696e3b636861727365743d7574662d38004c647b2270223a22736e73222c226f70223a22757064617465222c226e616d65223a2268657265222c22706572736f6e616c5f6e616d65223a2279697a68656e66656e67222c22706572736f6e616c5f64657363223a2231323334203837363520313638227d6821c16a11672055d3ad2b612dc3372a7101f402816920842ce10c1aeeff3de093c72f00000000",
"txid": "7f551414f35e270415de3199396c93a097fd65264e805b2d0213c08c6bcfaa85",
"hash": "bb8c41b018f6c4539102be484c5ad1326adf1ab152a58e6d123c78f0f896943d",
"depends": [
3
],
"fee": 173,
"sigops": 0,
"weight": 650
},
{
"data": "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",
"txid": "1a739e3ece13dd70b9e2d7184e31609e158ba0f8962a5eea76bf6c1d5579ae7b",
"hash": "1a739e3ece13dd70b9e2d7184e31609e158ba0f8962a5eea76bf6c1d5579ae7b",
"depends": [
],
"fee": 398,
"sigops": 0,
"weight": 1592
}
],
"coinbaseaux": {
},
"coinbasevalue": 5000001628,
"longpollid": "00000000000000308df706a8736dfe78eee7cea416adc1dc5bfcf4bc11202f6c324",
"target": "00000000ffff0000000000000000000000000000000000000000000000000000",
"mintime": 1724919762,
"mutable": [
"time",
"transactions",
"prevblock"
],
"noncerange": "00000000ffffffff",
"sigoplimit": 80000,
"sizelimit": 4000000,
"weightlimit": 4000000,
"curtime": 1724920984,
"bits": "1d00ffff",
"height": 41642,
"default_witness_commitment": "6a24aa21a9ed9392f1fe90c4f596eda2d286bba00dc8e2d66c0ec049783f9893f11043575063"
}

As you can see, "bits" field is set into "1d00ffff", and the time of the block is pushed forward. If you can see the real difficulty instead, then your CPU miner will try to mine a block with that difficulty, and will probably fail to do that on time.

In general, I can see two options:

1. Modifying Bitcoin Core.
2. Having unmodified Bitcoin Core, getting original block template, and modifying it in your mining software, or just before passing it to your mining software.

I think it is easier to recompile Bitcoin Core, but it is possible to get for example some 80-byte block header, and then write some code, to replace block time and difficulty, and then pass it into some mining software. Also, mining with Bitcoin Core is easier, because then you don't have to worry about dumping the whole block, making a proper Segwit commitment, and so on.

LoyceV

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Activity: 3290

Merit: 16489

Thick-Skinned Gang Leader and Golden Feather 2021

Quote from: BlackHatCoiner on August 29, 2024, 04:14:59 AM

Quote from: ercewubam on June 09, 2024, 10:53:36 AM

Test coins are weird: some of them are free, some of them are burned.

Both the "free" and the "burned" link to the same transaction.

They have different txids:
"free": 8f4cf55da2abc21ac4f5d176bd5aefcfdc91852343dbfe91215d7c8afa966baf
"burned": c3750456a633ddc6493b26fd5ef288b339e84f231f31128fd6d84276b8871abf

BlackHatCoiner

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Activity: 1512

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Farewell, Leo

Quote from: ercewubam on June 09, 2024, 10:53:36 AM

Test coins are weird: some of them are free, some of them are burned.

Both the "free" and the "burned" link to the same transaction. I get that the coinbase reward is burned, because it is sent to OP_RETURN, but where are the free coins?

Quote from: garlonicon on August 29, 2024, 03:12:03 AM

Of course, for CPU-based mining, some modifications are needed, but I think grinding coins with bitcoin-util should still be possible. I will think about some kind of such implementation.

What's the recommended way to mine testnet4 with CPU? Is it possible directly from Core with generatetoaddress? And, is there mining software for testnet that is configurable with GPUs?

LoyceV

legendary

Activity: 3290

Merit: 16489

Thick-Skinned Gang Leader and Golden Feather 2021

Quote from: ercewubam on June 09, 2024, 10:53:36 AM

Test coins are weird: some of them are free

Can you explain this one?

garlonicon

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Activity: 821

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Pawns are the soul of chess

Quote

but it's easier to just wait for testnet3 to be shredded and replaced by the new version by default

New version released: https://groups.google.com/g/bitcoindev/c/EmAOO-Nbmzw

It is release candidate, but it contains fully working testnet4 implementation.

Of course, for CPU-based mining, some modifications are needed, but I think grinding coins with bitcoin-util should still be possible. I will think about some kind of such implementation.

vjudeu

hero member

Activity: 813

Merit: 1944

Quote

This means you don't want to waste time waiting for your computer to compute millions of hashes to find the next block at difficulty one.

But that's the whole point! You want to do that, to make sure, that you are ready for testnet3 or testnet4 mining. For example, you want to abandon the idea of using unoptimized Python code for testnet mining. Or: a similar idea of using "sha256sum", running in a bash loop (and creating and destroying the whole ELF stack for computing every single hash).

1. If you mine with regtest difficulty, then you don't know, if you hit correct blocks by accident or not. Then, you can even manually increase nonce, and use "submitblock", to mine anything there.
2. In regtest, you have no difficulty adjustments, so you don't know, how many testnet blocks you could mine, with your current setup. You have to soft-fork that feature, or switch to signet, to learn it.
3. If your tests require more than 15k coins, then you won't do that on regtest. All other networks have 21 million coins. You need to cycle 15k coins, 1400 times, to reach similar outcome.
4. You cannot measure the actual effort of mining blocks with regtest. You can mine with maximum speed of 43,200 blocks per two hours, and increasing your computing power won't change it.

Also, I wonder, if I should create a pull request, which will bring CPU-only mining into Bitcoin Core, as a feature. Then, it could be similar to grinding blocks from bitcoin-util: it will always give you a block, matching the minimal difficulty, on all networks, including mainnet. Because in general, that's how testnet should probably work: you have a mainnet chain, up to the block 789,012, and then you say "I want to mine a block 789,013, with those transactions, and test that scenario". Because if testnet blocks are not stale, then they always have a chance to get some value, and be traded on centralized exchanges.

Topic: Requesting Testnet4 tBTC - page 2. (Read 874 times)