Mining Hardware – Why does my program crash after 30,000 iterations while performing a mining function on a blockchain?

I’ve been trying to build my own blockchain from scratch in Golang.

I coded the execution layer and recently completed implementing the consensus layer for my chain.

But there is one persistent problem. There is the following function used to mine a specific block:

func (bc *Blockchain) MineBlock(b *Block) error 
    bc.logger.Log(
        "msg", "mining block..",
    )
    var targetForBlock *big.Int
    var err error
    if (bc.Height() % HEIGHT_DIVISOR) == 0 
        targetForBlock, err = bc.calcTargetValue(b)
        bc.Target = targetForBlock
        if err != nil 
            return err
        
     else 
        targetForBlock = bc.Target
        fmt.Printf("target is %x\n", targetForBlock)
    
    fmt.Printf("target for block %x\n", targetForBlock)
    bHash := b.HashWithoutCache(BlockHasher)
    hashBigInt, _ := new(big.Int).SetString(bHash.String(), 16)
    for isLowerThanTarget(hashBigInt, targetForBlock) != -1 
        nonce := b.Header.Nonce
        b.Header.Nonce++
        bHash = b.HashWithoutCache(BlockHasher)
        hashBigInt.SetString(bHash.String(), 16)
        fmt.Printf("trying new combo with nonce %v block hash %s and target %x \n", nonce, bHash.String(), targetForBlock)
    

    // updating timestamp
    b.Header.Timestamp = uint64(time.Now().UnixNano())
    b.Header.Target = targetForBlock
    b.Header.NBits = targetToCompact(targetForBlock)

    fmt.Printf("block mined with hash %s and target %x \n", bHash.String(), targetForBlock)

    return nil

• First, the block’s target is calculated. The goal is adjusted every 5 blocks.
• Once complete, start mining. Hash the block and compare it to the target. If not, increase NONCE until the condition is resolved.

Here’s what tends to happen: After about 30,000 repetitions; My program simply crashes. I would like to know what I am doing wrong in my software architecture. The initial goals of the chain are: "0x00ffff0000000000000000000000000000000000000000000000000000"

Should I use a GPU for mining? How do I properly debug the problem?