Transaction

j"1LAnZuoQdcKCkpDBKQMCgziGMoPC4VQUckM<div class="post"><div class="quoteheader"><a href="https://bitcointalk.org/index.php?topic=1332.msg14966#msg14966">Quote from: theymos on October 02, 2010, 06:11:11 AM</a></div><div class="quote"><div class="quoteheader"><a href="https://bitcointalk.org/index.php?topic=1332.msg14960#msg14960">Quote from: lzsaver on October 02, 2010, 05:49:47 AM</a></div><div class="quote">Can you tell more about it:<br/>"they have to do weird things with extraNonce, which increases the size of the block header".<br/></div>When you generate, you calculate hashes of the block header. Hashing more data is slower than hashing less data, so the block header is critically of a fixed size for everyone, with one exception.</div>This is the point of confusion. &nbsp;extraNonce is not part of the block header, it is part of the first transaction. &nbsp;It does not slow down your hashing. &nbsp;It does not change the size of the header.<br/><br/>We need to be vigilant and nip in the bud any misconception that the contents of your block slows down your hash speed. &nbsp;It doesn't.<br/><br/>extraNonce never needs to be very big. &nbsp;We could reset it every second whenever the time changes if we wanted. &nbsp;Worst case, if you didn't want to keep track of incrementing it, extraNonce could be 4 random bytes and the chance of wasting time from collision would be negligible.<br/><br/>Separate machines are automatically collision proof because they have different generated public keys in the first transaction. &nbsp;That also goes for each thread too.<br/></div> text/html