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use better hashing (#149)
<!-- This is an auto-generated comment: release notes by coderabbit.ai --> ## Summary by CodeRabbit * **Refactor** * Internal hash implementation has been reorganized for improved code maintainability and performance. <sub>✏️ Tip: You can customize this high-level summary in your review settings.</sub> <!-- end of auto-generated comment: release notes by coderabbit.ai --> Signed-off-by: Robert Landers <[email protected]>
1 parent 4edaf51 commit b5f1386

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4 files changed

+29
-32
lines changed

4 files changed

+29
-32
lines changed

atlas/cache/cloxcache.go

Lines changed: 0 additions & 19 deletions
Original file line numberDiff line numberDiff line change
@@ -131,21 +131,6 @@ func (c *CloxCache[K, V]) Close() {
131131
close(c.stopDecay)
132132
}
133133

134-
// hashKey computes FNV-1a hash for string or []byte keys
135-
func hashKey[K Key](key K) uint64 {
136-
const offset64 = 14695981039346656037
137-
const prime64 = 1099511628211
138-
139-
hash := uint64(offset64)
140-
// Works for both string and []byte due to Key constraint
141-
for i := 0; i < len(key); i++ {
142-
hash ^= uint64(key[i])
143-
hash *= prime64
144-
}
145-
return hash
146-
}
147-
148-
// keysEqual compares two keys for equality
149134
func keysEqual[K Key](a, b K) bool {
150135
if len(a) != len(b) {
151136
return false
@@ -158,17 +143,13 @@ func keysEqual[K Key](a, b K) bool {
158143
return true
159144
}
160145

161-
// copyKey creates a copy of the key to prevent caller mutations from affecting stored data.
162-
// For []byte keys, this allocates a new slice and copies the data.
163-
// For string keys, this is a no-op since strings are immutable.
164146
func copyKey[K Key](key K) K {
165147
switch k := any(key).(type) {
166148
case []byte:
167149
cp := make([]byte, len(k))
168150
copy(cp, k)
169151
return any(cp).(K)
170152
default:
171-
// string and other ~string types are immutable, no copy needed
172153
return key
173154
}
174155
}

atlas/cache/hash.go

Lines changed: 24 additions & 0 deletions
Original file line numberDiff line numberDiff line change
@@ -0,0 +1,24 @@
1+
package cache
2+
3+
import (
4+
"unsafe"
5+
6+
"github.com/zeebo/xxh3"
7+
)
8+
9+
func hashKey[K Key](key K) uint64 {
10+
return xxh3.Hash(keyToBytes(key))
11+
}
12+
13+
func keyToBytes[K Key](key K) []byte {
14+
switch k := any(key).(type) {
15+
case []byte:
16+
return k
17+
case string:
18+
return unsafe.Slice(unsafe.StringData(k), len(k))
19+
default:
20+
// For ~string types, convert via string
21+
s := string(key)
22+
return unsafe.Slice(unsafe.StringData(s), len(s))
23+
}
24+
}

go.mod

Lines changed: 1 addition & 0 deletions
Original file line numberDiff line numberDiff line change
@@ -8,6 +8,7 @@ require (
88
github.com/dgraph-io/badger/v4 v4.8.0
99
github.com/spf13/cobra v1.10.1
1010
github.com/stretchr/testify v1.11.1
11+
github.com/zeebo/xxh3 v1.0.2
1112
go.uber.org/zap v1.27.1
1213
google.golang.org/grpc v1.77.0
1314
google.golang.org/protobuf v1.36.10

go.sum

Lines changed: 4 additions & 13 deletions
Original file line numberDiff line numberDiff line change
@@ -361,12 +361,14 @@ github.com/yuin/goldmark v1.7.13 h1:GPddIs617DnBLFFVJFgpo1aBfe/4xcvMc3SB5t/D0pA=
361361
github.com/yuin/goldmark v1.7.13/go.mod h1:ip/1k0VRfGynBgxOz0yCqHrbZXhcjxyuS66Brc7iBKg=
362362
github.com/yuin/goldmark-highlighting/v2 v2.0.0-20230729083705-37449abec8cc h1:+IAOyRda+RLrxa1WC7umKOZRsGq4QrFFMYApOeHzQwQ=
363363
github.com/yuin/goldmark-highlighting/v2 v2.0.0-20230729083705-37449abec8cc/go.mod h1:ovIvrum6DQJA4QsJSovrkC4saKHQVs7TvcaeO8AIl5I=
364-
github.com/zeebo/assert v1.1.0 h1:hU1L1vLTHsnO8x8c9KAR5GmM5QscxHg5RNU5z5qbUWY=
365-
github.com/zeebo/assert v1.1.0/go.mod h1:Pq9JiuJQpG8JLJdtkwrJESF0Foym2/D9XMU5ciN/wJ0=
364+
github.com/zeebo/assert v1.3.0 h1:g7C04CbJuIDKNPFHmsk4hwZDO5O+kntRxzaUoNXj+IQ=
365+
github.com/zeebo/assert v1.3.0/go.mod h1:Pq9JiuJQpG8JLJdtkwrJESF0Foym2/D9XMU5ciN/wJ0=
366366
github.com/zeebo/blake3 v0.2.4 h1:KYQPkhpRtcqh0ssGYcKLG1JYvddkEA8QwCM/yBqhaZI=
367367
github.com/zeebo/blake3 v0.2.4/go.mod h1:7eeQ6d2iXWRGF6npfaxl2CU+xy2Fjo2gxeyZGCRUjcE=
368368
github.com/zeebo/pcg v1.0.1 h1:lyqfGeWiv4ahac6ttHs+I5hwtH/+1mrhlCtVNQM2kHo=
369369
github.com/zeebo/pcg v1.0.1/go.mod h1:09F0S9iiKrwn9rlI5yjLkmrug154/YRW6KnnXVDM/l4=
370+
github.com/zeebo/xxh3 v1.0.2 h1:xZmwmqxHZA8AI603jOQ0tMqmBr9lPeFwGg6d+xy9DC0=
371+
github.com/zeebo/xxh3 v1.0.2/go.mod h1:5NWz9Sef7zIDm2JHfFlcQvNekmcEl9ekUZQQKCYaDcA=
370372
go.etcd.io/bbolt v1.4.3 h1:dEadXpI6G79deX5prL3QRNP6JB8UxVkqo4UPnHaNXJo=
371373
go.etcd.io/bbolt v1.4.3/go.mod h1:tKQlpPaYCVFctUIgFKFnAlvbmB3tpy1vkTnDWohtc0E=
372374
go.opentelemetry.io/auto/sdk v1.2.1 h1:jXsnJ4Lmnqd11kwkBV2LgLoFMZKizbCi5fNZ/ipaZ64=
@@ -513,27 +515,16 @@ golang.org/x/tools v0.39.0/go.mod h1:JnefbkDPyD8UU2kI5fuf8ZX4/yUeh9W877ZeBONxUqQ
513515
golang.org/x/xerrors v0.0.0-20190717185122-a985d3407aa7/go.mod h1:I/5z698sn9Ka8TeJc9MKroUUfqBBauWjQqLJ2OPfmY0=
514516
gonum.org/v1/gonum v0.16.0 h1:5+ul4Swaf3ESvrOnidPp4GZbzf0mxVQpDCYUQE7OJfk=
515517
gonum.org/v1/gonum v0.16.0/go.mod h1:fef3am4MQ93R2HHpKnLk4/Tbh/s0+wqD5nfa6Pnwy4E=
516-
google.golang.org/api v0.254.0 h1:jl3XrGj7lRjnlUvZAbAdhINTLbsg5dbjmR90+pTQvt4=
517-
google.golang.org/api v0.254.0/go.mod h1:5BkSURm3D9kAqjGvBNgf0EcbX6Rnrf6UArKkwBzAyqQ=
518518
google.golang.org/api v0.256.0 h1:u6Khm8+F9sxbCTYNoBHg6/Hwv0N/i+V94MvkOSor6oI=
519519
google.golang.org/api v0.256.0/go.mod h1:KIgPhksXADEKJlnEoRa9qAII4rXcy40vfI8HRqcU964=
520520
google.golang.org/genproto v0.0.0-20250603155806-513f23925822 h1:rHWScKit0gvAPuOnu87KpaYtjK5zBMLcULh7gxkCXu4=
521521
google.golang.org/genproto v0.0.0-20250603155806-513f23925822/go.mod h1:HubltRL7rMh0LfnQPkMH4NPDFEWp0jw3vixw7jEM53s=
522-
google.golang.org/genproto/googleapis/api v0.0.0-20251022142026-3a174f9686a8 h1:mepRgnBZa07I4TRuomDE4sTIYieg/osKmzIf4USdWS4=
523-
google.golang.org/genproto/googleapis/api v0.0.0-20251022142026-3a174f9686a8/go.mod h1:fDMmzKV90WSg1NbozdqrE64fkuTv6mlq2zxo9ad+3yo=
524522
google.golang.org/genproto/googleapis/api v0.0.0-20251124214823-79d6a2a48846 h1:ZdyUkS9po3H7G0tuh955QVyyotWvOD4W0aEapeGeUYk=
525523
google.golang.org/genproto/googleapis/api v0.0.0-20251124214823-79d6a2a48846/go.mod h1:Fk4kyraUvqD7i5H6S43sj2W98fbZa75lpZz/eUyhfO0=
526-
google.golang.org/genproto/googleapis/rpc v0.0.0-20251022142026-3a174f9686a8 h1:M1rk8KBnUsBDg1oPGHNCxG4vc1f49epmTO7xscSajMk=
527-
google.golang.org/genproto/googleapis/rpc v0.0.0-20251022142026-3a174f9686a8/go.mod h1:7i2o+ce6H/6BluujYR+kqX3GKH+dChPTQU19wjRPiGk=
528-
google.golang.org/genproto/googleapis/rpc v0.0.0-20251103181224-f26f9409b101 h1:tRPGkdGHuewF4UisLzzHHr1spKw92qLM98nIzxbC0wY=
529-
google.golang.org/genproto/googleapis/rpc v0.0.0-20251103181224-f26f9409b101/go.mod h1:7i2o+ce6H/6BluujYR+kqX3GKH+dChPTQU19wjRPiGk=
530-
google.golang.org/genproto/googleapis/rpc v0.0.0-20251111163417-95abcf5c77ba/go.mod h1:7i2o+ce6H/6BluujYR+kqX3GKH+dChPTQU19wjRPiGk=
531524
google.golang.org/genproto/googleapis/rpc v0.0.0-20251124214823-79d6a2a48846 h1:Wgl1rcDNThT+Zn47YyCXOXyX/COgMTIdhJ717F0l4xk=
532525
google.golang.org/genproto/googleapis/rpc v0.0.0-20251124214823-79d6a2a48846/go.mod h1:7i2o+ce6H/6BluujYR+kqX3GKH+dChPTQU19wjRPiGk=
533526
google.golang.org/grpc v1.77.0 h1:wVVY6/8cGA6vvffn+wWK5ToddbgdU3d8MNENr4evgXM=
534527
google.golang.org/grpc v1.77.0/go.mod h1:z0BY1iVj0q8E1uSQCjL9cppRj+gnZjzDnzV0dHhrNig=
535-
google.golang.org/grpc/cmd/protoc-gen-go-grpc v1.5.1 h1:F29+wU6Ee6qgu9TddPgooOdaqsxTMunOoj8KA5yuS5A=
536-
google.golang.org/grpc/cmd/protoc-gen-go-grpc v1.5.1/go.mod h1:5KF+wpkbTSbGcR9zteSqZV6fqFOWBl4Yde8En8MryZA=
537528
google.golang.org/grpc/cmd/protoc-gen-go-grpc v1.6.0 h1:6Al3kEFFP9VJhRz3DID6quisgPnTeZVr4lep9kkxdPA=
538529
google.golang.org/grpc/cmd/protoc-gen-go-grpc v1.6.0/go.mod h1:QLvsjh0OIR0TYBeiu2bkWGTJBUNQ64st52iWj/yA93I=
539530
google.golang.org/protobuf v1.36.10 h1:AYd7cD/uASjIL6Q9LiTjz8JLcrh/88q5UObnmY3aOOE=

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