zkSync NonceHolder | Is it a smart contract that essentially holds a mapping of all addresses -> all nonces?

Question

According to the zkSync documentation

[The] NonceHolder serves as storage for nonces for our accounts.

Does this mean it literally has every single address/account and a mapping of all their nonces?

Answer 1

According to the zkSync AI Bot:

Yes, the NonceHolder in zkSync is a system contract that serves as a centralized storage for account nonces. It efficiently manages both transaction nonces and deployment nonces in a single storage location. This design not only simplifies the process for the operator to manage and order transactions but also ensures that each pair of address and nonce remains unique, enhancing the security and integrity of the system.

The NonceHolder system contract is crucial for maintaining the order and validity of transactions within the zkSync network, and it plays a significant role in preventing replay attacks by ensuring that each transaction nonce is used only once.