Implement Nibbles to reduce memory allocations #207
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This commit implements Nibbles and implements them for insert and proofs only. See the docs inline for details of what Nibbles are and how they are used.
| self.split( | ||
| node, | ||
| &mut parents, | ||
| &chunked_key[key_nib_offset..], | ||
| &rem_path, |
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There's a more efficient way to do this, but it requires changes in split. Maybe you can add a todo and we can get rid of the allocation for rem_path.
In any case, it is better since you aren't allocating key_nib_offet bytes.
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I think there are a LOT of improvements possible here, not sure that this one is worse than some of the others I already know about.
firewood/src/merkle.rs
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| || !remaining_path | ||
| .iter() | ||
| .take(n_path.len()) | ||
| .eq(n_path.iter().cloned()) |
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I find these multi-line-if clauses super cumbersome to read; think we could pop this out into a variable (with a name that explains why we are going this too)?
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I split it into two if statements; I think it's a bit easier to read now.
firewood/src/nibbles.rs
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| static NIBBLES: [u8; 16] = [0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15]; | ||
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| /// Nibbles is a newtype that contains only a pointer to a u8, and produces |
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| /// Nibbles is a newtype that contains only a pointer to a u8, and produces | |
| /// Nibbles is a newtype that contains only a reference to a `[u8]`, and produces |
firewood/src/nibbles.rs
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| pub struct Nibbles<'a, const LEADING_ZEROES: usize>(pub &'a [u8]); | ||
| impl<'a, const LEADING_ZEROES: usize> Index<usize> for Nibbles<'a, LEADING_ZEROES> { |
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| pub struct Nibbles<'a, const LEADING_ZEROES: usize>(pub &'a [u8]); | |
| impl<'a, const LEADING_ZEROES: usize> Index<usize> for Nibbles<'a, LEADING_ZEROES> { | |
| pub struct Nibbles<'a, const LEADING_ZEROES: usize>(pub &'a [u8]); | |
| impl<'a, const LEADING_ZEROES: usize> Index<usize> for Nibbles<'a, LEADING_ZEROES> { |
| #[must_use] | ||
| pub fn len(&self) -> usize { | ||
| LEADING_ZEROES + 2 * self.0.len() | ||
| } |
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This might be useful for improving that split function and taking in Nibbles instead of &[u8]
- Added additional comments to complex if statement - doc: pointer -> reference - and more whitespace
This commit implements Nibbles and implements them for insert and proofs only.
See the docs inline for details of what Nibbles are and how they are used.