diff --git a/Cargo.lock b/Cargo.lock
index 290d715f2c..beb94384d0 100644
--- a/Cargo.lock
+++ b/Cargo.lock
@@ -61,6 +61,18 @@ dependencies = [
  "backtrace",
 ]
 
+[[package]]
+name = "as-slice"
+version = "0.1.5"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "45403b49e3954a4b8428a0ac21a4b7afadccf92bfd96273f1a58cd4812496ae0"
+dependencies = [
+ "generic-array 0.12.4",
+ "generic-array 0.13.3",
+ "generic-array 0.14.5",
+ "stable_deref_trait",
+]
+
 [[package]]
 name = "async-compression"
 version = "0.3.12"
@@ -240,7 +252,7 @@ version = "0.9.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "4152116fd6e9dadb291ae18fc1ec3575ed6d84c29642d97890f4b4a3417297e4"
 dependencies = [
- "generic-array",
+ "generic-array 0.14.5",
 ]
 
 [[package]]
@@ -555,7 +567,7 @@ version = "0.10.1"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "bff07008ec701e8028e2ceb8f83f0e4274ee62bd2dbdc4fefff2e9a91824081a"
 dependencies = [
- "generic-array",
+ "generic-array 0.14.5",
  "subtle",
 ]
 
@@ -565,7 +577,7 @@ version = "0.11.1"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "b1d1a86f49236c215f271d40892d5fc950490551400b02ef360692c29815c714"
 dependencies = [
- "generic-array",
+ "generic-array 0.14.5",
  "subtle",
 ]
 
@@ -642,7 +654,7 @@ version = "0.9.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "d3dd60d1080a57a05ab032377049e0591415d2b31afd7028356dbf3cc6dcb066"
 dependencies = [
- "generic-array",
+ "generic-array 0.14.5",
 ]
 
 [[package]]
@@ -855,6 +867,24 @@ dependencies = [
  "slab",
 ]
 
+[[package]]
+name = "generic-array"
+version = "0.12.4"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "ffdf9f34f1447443d37393cc6c2b8313aebddcd96906caf34e54c68d8e57d7bd"
+dependencies = [
+ "typenum",
+]
+
+[[package]]
+name = "generic-array"
+version = "0.13.3"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "f797e67af32588215eaaab8327027ee8e71b9dd0b2b26996aedf20c030fce309"
+dependencies = [
+ "typenum",
+]
+
 [[package]]
 name = "generic-array"
 version = "0.14.5"
@@ -935,6 +965,15 @@ version = "1.8.2"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "eabb4a44450da02c90444cf74558da904edde8fb4e9035a9a6a4e15445af0bd7"
 
+[[package]]
+name = "hash32"
+version = "0.1.1"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "d4041af86e63ac4298ce40e5cca669066e75b6f1aa3390fe2561ffa5e1d9f4cc"
+dependencies = [
+ "byteorder",
+]
+
 [[package]]
 name = "hashbrown"
 version = "0.9.1"
@@ -953,6 +992,18 @@ dependencies = [
  "ahash 0.7.6",
 ]
 
+[[package]]
+name = "heapless"
+version = "0.6.1"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "634bd4d29cbf24424d0a4bfcbf80c6960129dc24424752a7d1d1390607023422"
+dependencies = [
+ "as-slice",
+ "generic-array 0.14.5",
+ "hash32",
+ "stable_deref_trait",
+]
+
 [[package]]
 name = "hermit-abi"
 version = "0.1.19"
@@ -1478,6 +1529,7 @@ dependencies = [
  "postgres_ffi",
  "rand",
  "regex",
+ "rstar",
  "rust-s3",
  "scopeguard",
  "serde",
@@ -1524,6 +1576,12 @@ dependencies = [
  "winapi",
 ]
 
+[[package]]
+name = "pdqselect"
+version = "0.1.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "4ec91767ecc0a0bbe558ce8c9da33c068066c57ecc8bb8477ef8c1ad3ef77c27"
+
 [[package]]
 name = "peeking_take_while"
 version = "0.1.2"
@@ -2014,6 +2072,18 @@ dependencies = [
  "regex",
 ]
 
+[[package]]
+name = "rstar"
+version = "0.9.2"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "1fc6fc513b8c3853e43a0c3f909ded14ffa82e5170c9c5f6fb175f9c85c8a433"
+dependencies = [
+ "heapless",
+ "num-traits",
+ "pdqselect",
+ "smallvec",
+]
+
 [[package]]
 name = "rust-ini"
 version = "0.17.0"
@@ -2351,6 +2421,12 @@ version = "0.5.2"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "6e63cff320ae2c57904679ba7cb63280a3dc4613885beafb148ee7bf9aa9042d"
 
+[[package]]
+name = "stable_deref_trait"
+version = "1.2.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "a8f112729512f8e442d81f95a8a7ddf2b7c6b8a1a6f509a95864142b30cab2d3"
+
 [[package]]
 name = "stringprep"
 version = "0.1.2"
diff --git a/pageserver/src/layered_repository.rs b/pageserver/src/layered_repository.rs
index 0be556ec28..4723a4f649 100644
--- a/pageserver/src/layered_repository.rs
+++ b/pageserver/src/layered_repository.rs
@@ -2140,7 +2140,7 @@ pub mod tests {
         let tline = repo.create_empty_timeline(TIMELINE_ID, Lsn(0))?;
 
         #[allow(non_snake_case)]
-        let TEST_KEY: Key = Key::from_hex("112222222233333333444444445500000001").unwrap();
+        let TEST_KEY: Key = Key::from_hex("110000222233333333444444445500000001").unwrap();
 
         let writer = tline.writer();
         writer.put(TEST_KEY, Lsn(0x10), Value::Image(TEST_IMG("foo at 0x10")))?;
@@ -2196,7 +2196,7 @@ pub mod tests {
 
         let mut keyspace = KeySpaceAccum::new();
 
-        let mut test_key = Key::from_hex("012222222233333333444444445500000000").unwrap();
+        let mut test_key = Key::from_hex("010000222233333333444444445500000000").unwrap();
         let mut blknum = 0;
         for _ in 0..50 {
             for _ in 0..1000 {
@@ -2239,7 +2239,7 @@ pub mod tests {
 
         const NUM_KEYS: usize = 1000;
 
-        let mut test_key = Key::from_hex("012222222233333333444444445500000000").unwrap();
+        let mut test_key = Key::from_hex("010000222233333333444444445500000000").unwrap();
 
         let mut keyspace = KeySpaceAccum::new();
 
@@ -2313,7 +2313,7 @@ pub mod tests {
 
         const NUM_KEYS: usize = 1000;
 
-        let mut test_key = Key::from_hex("012222222233333333444444445500000000").unwrap();
+        let mut test_key = Key::from_hex("010000222233333333444444445500000000").unwrap();
 
         let mut keyspace = KeySpaceAccum::new();
 
diff --git a/pageserver/src/repository.rs b/pageserver/src/repository.rs
index e2808e23bd..c21751a39b 100644
--- a/pageserver/src/repository.rs
+++ b/pageserver/src/repository.rs
@@ -596,7 +596,7 @@ mod tests {
     use lazy_static::lazy_static;
 
     lazy_static! {
-        static ref TEST_KEY: Key = Key::from_array(hex!("112222222233333333444444445500000001"));
+        static ref TEST_KEY: Key = Key::from_array(hex!("110000222233333333444444445500000001"));
     }
 
     #[test]
@@ -639,9 +639,9 @@ mod tests {
         use std::str::from_utf8;
 
         #[allow(non_snake_case)]
-        let TEST_KEY_A: Key = Key::from_hex("112222222233333333444444445500000001").unwrap();
+        let TEST_KEY_A: Key = Key::from_hex("110000222233333333444444445500000001").unwrap();
         #[allow(non_snake_case)]
-        let TEST_KEY_B: Key = Key::from_hex("112222222233333333444444445500000002").unwrap();
+        let TEST_KEY_B: Key = Key::from_hex("110000222233333333444444445500000002").unwrap();
 
         // Insert a value on the timeline
         writer.put(TEST_KEY_A, Lsn(0x20), test_value("foo at 0x20"))?;