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0 pointsglobular-toast2y ago0 comments

It's a trade off. Immutability is a big enough win to pay the price of a few extra CPU cycles. In practice it's very quick anyway. Computers are very good at adding numbers together (it's almost like it's what they were made for!). I keep all my accounts for over 12 years in one file and I still don't notice any delay when calculating balances etc.

If it does become a problem then one solution is to take sums at some point in time and start the ledger again paying each account from a contra account containing the previous balance.

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BillyTheKing2y ago· 1 in thread

I mean, yes for personal accounts with a couple of thousand transactions - sure. But esp. in payments or in exchanges there can be accounts with millions of transactions a day. So you get a double-whammy - those are hot-accounts which also slow down the system, recalculating the balance for those accounts each time a transaction happens isn't an option

globular-toastOP2y ago

Another way to do it is to keep the balances online. This is how something like Bitcoin works which is essentially one giant public ledger. It's a classic time/memory trade off.

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