btcd/blockchain/blockindex_test.go
Calvin Kim f396b3d3d9 blockchain: better Ancestor with skiplists
On startup, Ancestor call was taking a lot of time when the node was
loading the blockindex onto memory. This change speeds up the Ancestor
function significantly and speeds up the node during startup.

On testnet3 at blockheight ~2,500,000, the startup was around 30seconds
on current main and was 5 seconds with this change. Below is a benchstat
result showing the significant speedup.

goos: darwin
goarch: arm64
pkg: github.com/utreexo/utreexod/blockchain
           │     old.txt      │               new.txt                │
           │      sec/op      │    sec/op     vs base                │
Ancestor-8   120819.301µ ± 5%   7.013µ ± 19%  -99.99% (p=0.000 n=10)

           │  old.txt   │            new.txt             │
           │    B/op    │    B/op     vs base            │
Ancestor-8   0.000 ± 0%   0.000 ± 0%  ~ (p=1.000 n=10) ¹
¹ all samples are equal

           │  old.txt   │            new.txt             │
           │ allocs/op  │ allocs/op   vs base            │
Ancestor-8   0.000 ± 0%   0.000 ± 0%  ~ (p=1.000 n=10) ¹
¹ all samples are equal
2023-11-17 16:55:58 +09:00

43 lines
1.1 KiB
Go

// Copyright (c) 2023 The utreexo developers
// Use of this source code is governed by an ISC
// license that can be found in the LICENSE file.
package blockchain
import (
"math/rand"
"testing"
)
func TestAncestor(t *testing.T) {
height := 500_000
blockNodes := chainedNodes(nil, height)
for i, blockNode := range blockNodes {
// Grab a random node that's a child of this node
// and try to fetch the current blockNode with Ancestor.
randNode := blockNodes[rand.Intn(height-i)+i]
got := randNode.Ancestor(blockNode.height)
// See if we got the right one.
if got.hash != blockNode.hash {
t.Fatalf("expected ancestor at height %d "+
"but got a node at height %d",
blockNode.height, got.height)
}
// Gensis doesn't have ancestors so skip the check below.
if blockNode.height == 0 {
continue
}
// The ancestors are deterministic so check that this node's
// ancestor is the correct one.
if blockNode.ancestor.height != getAncestorHeight(blockNode.height) {
t.Fatalf("expected anestor at height %d, but it was at %d",
getAncestorHeight(blockNode.height),
blockNode.ancestor.height)
}
}
}