Originally, these metrics were added to track the largest storage wiping.
Since account self-destruction was deprecated with the Cancun fork,
these metrics have become meaningless.
As SELF-DESTRUCT opcode is disabled in the cancun fork(unless the
account is created within the same transaction, nothing to delete
in this case). The account will only be deleted in the following
cases:
- The account is created within the same transaction. In this case
the original storage was empty.
- The account is empty(zero nonce, zero balance, zero code) and
is touched within the transaction. Fortunately this kind of accounts
are not-existent on ethereum-mainnet.
All in all, after cancun, we are pretty sure there is no large contract
deletion and we don't need this mechanism for oom protection.
This change makes the StateDB track the state key value diff of a block transition.
We already tracked current account and storage values for the purpose of updating
the state snapshot. With this PR, we now also track the original (pre-transition) values
of accounts and storage slots.
This PR contains a small portion of the full pbss PR, namely
Remove the tracer from trie (and comitter), and instead using an accessList.
Related changes to the Nodeset.
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Co-authored-by: Gary Rong <garyrong0905@gmail.com>
