diff --git a/crates/text/src/locator.rs b/crates/text/src/locator.rs
index 0a22ea58f9..249e79b6fd 100644
--- a/crates/text/src/locator.rs
+++ b/crates/text/src/locator.rs
@@ -2,23 +2,28 @@ use smallvec::{smallvec, SmallVec};
 use std::iter;
 
 #[derive(Clone, Debug, PartialEq, Eq, PartialOrd, Ord, Hash)]
-pub struct Locator(SmallVec<[u8; 4]>);
+pub struct Locator(SmallVec<[u64; 4]>);
 
 impl Locator {
     pub fn min() -> Self {
-        Self(smallvec![u8::MIN])
+        Self(smallvec![u64::MIN])
     }
 
     pub fn max() -> Self {
-        Self(smallvec![u8::MAX])
+        Self(smallvec![u64::MAX])
+    }
+
+    pub fn assign(&mut self, other: &Self) {
+        self.0.resize(other.0.len(), 0);
+        self.0.copy_from_slice(&other.0);
     }
 
     pub fn between(lhs: &Self, rhs: &Self) -> Self {
-        let lhs = lhs.0.iter().copied().chain(iter::repeat(u8::MIN));
-        let rhs = rhs.0.iter().copied().chain(iter::repeat(u8::MAX));
+        let lhs = lhs.0.iter().copied().chain(iter::repeat(u64::MIN));
+        let rhs = rhs.0.iter().copied().chain(iter::repeat(u64::MAX));
         let mut location = SmallVec::new();
         for (lhs, rhs) in lhs.zip(rhs) {
-            let mid = lhs + (rhs.saturating_sub(lhs)) / 2;
+            let mid = lhs + ((rhs.saturating_sub(lhs)) >> 48);
             location.push(mid);
             if mid > lhs {
                 break;
@@ -26,6 +31,10 @@ impl Locator {
         }
         Self(location)
     }
+
+    pub fn len(&self) -> usize {
+        self.0.len()
+    }
 }
 
 impl Default for Locator {
diff --git a/crates/text/src/text.rs b/crates/text/src/text.rs
index c2e0d8e4ef..3985501659 100644
--- a/crates/text/src/text.rs
+++ b/crates/text/src/text.rs
@@ -2002,7 +2002,7 @@ impl sum_tree::Summary for FragmentSummary {
     type Context = Option<clock::Global>;
 
     fn add_summary(&mut self, other: &Self, _: &Self::Context) {
-        self.max_id = other.max_id.clone();
+        self.max_id.assign(&other.max_id);
         self.text.visible += &other.text.visible;
         self.text.deleted += &other.text.deleted;
         self.max_version.join(&other.max_version);
@@ -2113,7 +2113,7 @@ impl<'a> sum_tree::Dimension<'a, FragmentSummary> for FullOffset {
 
 impl<'a> sum_tree::Dimension<'a, FragmentSummary> for Locator {
     fn add_summary(&mut self, summary: &FragmentSummary, _: &Option<clock::Global>) {
-        *self = summary.max_id.clone();
+        self.assign(&summary.max_id);
     }
 }