diff --git a/linalg/Cargo.toml b/linalg/Cargo.toml
index 74964e12fb..a120d58bbd 100644
--- a/linalg/Cargo.toml
+++ b/linalg/Cargo.toml
@@ -25,6 +25,7 @@ num-traits = "0.2.14"
 tract-data = { path = "../data" }
 paste = "1.0.5"
 scan_fmt = "0.2.6"
+strength_reduce = "0.2"
 
 [build-dependencies]
 cc = "1.0.69"
diff --git a/linalg/src/frame/pack.rs b/linalg/src/frame/pack.rs
index 74bed74cae..086008b984 100644
--- a/linalg/src/frame/pack.rs
+++ b/linalg/src/frame/pack.rs
@@ -1,19 +1,23 @@
 use std::fmt::Debug;
 use std::marker::PhantomData;
 use std::ops::Range;
+use strength_reduce::StrengthReducedUsize;
 use tract_data::internal::*;
 
-#[derive(Clone, Debug, Eq, PartialEq, Educe)]
-#[educe(Hash)]
+#[derive(Clone, Debug, Educe)]
+#[educe(Hash, PartialEq, Eq)]
 pub struct Packer {
     pub r: usize,
     alignment: usize,
     end_padding_record: usize,
+    #[educe(PartialEq(ignore))]
+    #[educe(Hash(ignore))]
+    r_reduced: StrengthReducedUsize,
 }
 
 impl Packer {
     pub fn new(nr: usize, alignment: usize, end_padding_record: usize) -> Packer {
-        Packer { r: nr, alignment, end_padding_record }
+        Packer { r: nr, alignment, end_padding_record, r_reduced: StrengthReducedUsize::new(nr) }
     }
 
     pub fn alignment(&self) -> usize {
@@ -126,7 +130,7 @@ impl Packer {
         k: usize,
         mn: usize,
     ) -> KOutWriter<'p, T> {
-        KOutWriter::new(pb, self.r, mn, k)
+        KOutWriter::new(pb, self.r_reduced, mn, k)
     }
 
     pub fn write_single_panel_with_k_outer<'p, T: Copy + Debug>(
@@ -142,7 +146,7 @@ impl Packer {
         k: usize,
         mn: usize,
     ) -> KInWriter<'p, T> {
-        KInWriter::new(pb, self.r, mn, k)
+        KInWriter::new(pb, self.r_reduced, mn, k)
     }
 }
 
@@ -201,19 +205,25 @@ impl<'p, T> KOutWriter<'p, T>
 where
     T: Copy + std::fmt::Debug,
 {
-    pub fn new(ptr: *mut T, panel_width: usize, mn: usize, k: usize) -> KOutWriter<'p, T> {
-        let panels = (mn + panel_width - 1) / panel_width;
-        let last_panel_width = mn - (panels - 1) * panel_width;
+    pub fn new(
+        ptr: *mut T,
+        panel_width_reduced: StrengthReducedUsize,
+        mn: usize,
+        k: usize,
+    ) -> KOutWriter<'p, T> {
+        let (div, rem) = StrengthReducedUsize::div_rem(mn, panel_width_reduced);
+        let (panels, last_panel_width) =
+            if rem > 0 { (div + 1, rem) } else { (div, panel_width_reduced.get()) };
         KOutWriter {
             ptr,
             panels,
-            panel_width,
+            panel_width: panel_width_reduced.get(),
             last_panel_width,
-            remain: if panels > 1 { panel_width } else { last_panel_width },
+            remain: if panels > 1 { panel_width_reduced.get() } else { last_panel_width },
             current_panel: 0,
-            next_panel: ((k - 1) * panel_width) as isize,
-            next_lane: panel_width as isize
-                - ((last_panel_width + (panels - 1) * panel_width * k) as isize),
+            next_panel: ((k - 1) * panel_width_reduced.get()) as isize,
+            next_lane: panel_width_reduced.get() as isize
+                - ((last_panel_width + (panels - 1) * panel_width_reduced.get() * k) as isize),
             _phantom: PhantomData,
         }
     }
@@ -269,20 +279,26 @@ impl<'p, T> KInWriter<'p, T>
 where
     T: Copy + Debug,
 {
-    pub fn new(ptr: *mut T, panel_width: usize, mn: usize, k: usize) -> KInWriter<'p, T> {
-        let panels = (mn + panel_width - 1) / panel_width;
-        let last_panel_width = mn - (panels - 1) * panel_width;
+    pub fn new(
+        ptr: *mut T,
+        panel_width_reduced: StrengthReducedUsize,
+        mn: usize,
+        k: usize,
+    ) -> KInWriter<'p, T> {
+        let (div, rem) = StrengthReducedUsize::div_rem(mn, panel_width_reduced);
+        let (panels, last_panel_width) =
+            if rem > 0 { (div + 1, rem) } else { (div, panel_width_reduced.get()) };
         KInWriter {
             ptr,
             k,
             panels,
-            panel_width,
+            panel_width: panel_width_reduced.get(),
             last_panel_width,
             remain_on_k: k,
-            remain_on_mn: if panels == 1 { last_panel_width } else { panel_width },
+            remain_on_mn: if panels == 1 { last_panel_width } else { panel_width_reduced.get() },
             current_panel: 0,
-            next_mn_offset: 1 - (k * panel_width) as isize,
-            next_panel_offset: 1 - panel_width as isize,
+            next_mn_offset: 1 - (k * panel_width_reduced.get()) as isize,
+            next_panel_offset: 1 - panel_width_reduced.get() as isize,
             _phantom: PhantomData,
         }
     }
@@ -325,7 +341,7 @@ pub unsafe fn pack_mn_major<Chunk: Copy>(
     mn_range_bytes: Range<usize>,
     k_range: Range<usize>,
 ) {
-    let mnr = std::mem::size_of::<Chunk>();
+    let mnr:usize = std::mem::size_of::<Chunk>();
     let full_panes = mn_range_bytes.len() / mnr;
     let partial_pane = mn_range_bytes.len() % mnr;
     for k in 0..k_range.len() {