diff --git a/CHANGELOG.md b/CHANGELOG.md
index b6ece53..ed4f567 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -8,6 +8,8 @@ Performance improvements:
   Don't resolve helper binaries on Windows when `-z/--search-zip` isn't used.
 * [PERF #2865](https://github.com/BurntSushi/ripgrep/pull/2865):
   Avoid using path canonicalization on Windows when emitting hyperlinks.
+* [PERF #3184](https://github.com/BurntSushi/ripgrep/pull/3184):
+  Improve performance of large values with `-A/--after-context`.
 
 Bug fixes:
 
diff --git a/crates/searcher/src/line_buffer.rs b/crates/searcher/src/line_buffer.rs
index 2a7ff09..5bc49db 100644
--- a/crates/searcher/src/line_buffer.rs
+++ b/crates/searcher/src/line_buffer.rs
@@ -415,21 +415,26 @@ impl LineBuffer {
         assert_eq!(self.pos, 0);
         loop {
             self.ensure_capacity()?;
-            let readlen = rdr.read(self.free_buffer().as_bytes_mut())?;
-            if readlen == 0 {
-                // We're only done reading for good once the caller has
-                // consumed everything.
-                self.last_lineterm = self.end;
-                return Ok(!self.buffer().is_empty());
+            let oldend = self.end;
+            while !self.free_buffer().is_empty() {
+                let readlen = rdr.read(self.free_buffer())?;
+                if readlen == 0 {
+                    break;
+                }
+                self.end += readlen;
             }
 
             // Get a mutable view into the bytes we've just read. These are
             // the bytes that we do binary detection on, and also the bytes we
             // search to find the last line terminator. We need a mutable slice
             // in the case of binary conversion.
-            let oldend = self.end;
-            self.end += readlen;
             let newbytes = &mut self.buf[oldend..self.end];
+            if newbytes.is_empty() {
+                self.last_lineterm = self.end;
+                // We're only done reading for good once the caller has
+                // consumed everything.
+                return Ok(!self.buffer().is_empty());
+            }
 
             // Binary detection.
             match self.config.binary {
diff --git a/crates/searcher/src/searcher/glue.rs b/crates/searcher/src/searcher/glue.rs
index defb9c4..7c94307 100644
--- a/crates/searcher/src/searcher/glue.rs
+++ b/crates/searcher/src/searcher/glue.rs
@@ -737,7 +737,7 @@ d
         // Namely, it will *always* detect binary data in the current buffer
         // before searching it. Thus, the total number of bytes searched is
         // smaller than below.
-        let exp = "0:a\n\nbyte count:262146\nbinary offset:262153\n";
+        let exp = "0:a\n\nbyte count:262142\nbinary offset:262153\n";
         // In contrast, the slice readers (for multi line as well) will only
         // look for binary data in the initial chunk of bytes. After that
         // point, it only looks for binary data in matches. Note though that
@@ -771,7 +771,7 @@ d
         haystack.push_str("a\x00a\n");
         haystack.push_str("a\n");
 
-        let exp = "0:a\n\nbyte count:262146\nbinary offset:262149\n";
+        let exp = "0:a\n\nbyte count:262142\nbinary offset:262149\n";
         // The binary offset for the Slice readers corresponds to the binary
         // data in `a\x00a\n` since the first line with binary data
         // (`b\x00b\n`) isn't part of a match, and is therefore undetected.