diff --git a/equal-benchmark.scm b/equal-benchmark.scm
new file mode 100644
index 00000000..37e9fbea
--- /dev/null
+++ b/equal-benchmark.scm
@@ -0,0 +1,144 @@
+
+(import (scheme base)
+        (scheme read)
+        (scheme write)
+        (scheme time))
+
+; Returns a list with n elements, all equal to x.
+
+(define (make-test-list1 n x)
+  (if (zero? n)
+      '()
+      (cons x (make-test-list1 (- n 1) x))))
+
+; Returns a list of n lists, each consisting of n x's.
+; The n elements of the outer list are actually the same list.
+
+(define (make-test-tree1 n)
+  (if (zero? n)
+      '()
+      (make-test-list1 n (make-test-tree1 (- n 1)))))
+
+
+
+; Calls the thunk n times.
+
+(define (iterate n thunk)
+  (cond ((= n 1)
+         (thunk))
+        ((> n 1)
+         (thunk)
+         (iterate (- n 1) thunk))
+        (else #f)))      
+
+
+; DAG with much sharing.
+; 10 is a good parameter for n.
+
+(define (equality-benchmark1 n)
+  (let ((x (make-test-tree1 n))
+        (y (make-test-tree1 n)))
+
+(write 1) (newline)
+(write (make-test-tree1 1)) (newline)
+(write 2) (newline)
+(write (make-test-tree1 2)) (newline)
+(write 3) (newline)
+(write (make-test-tree1 3)) (newline)
+    (write x) 
+    (newline)
+    (equal? x y)))
+    ;(iterate n (hide n (lambda () (equal? x y))))))
+
+
+(define (equality-benchmarks n0 n1 n2 n3 n4 n5)
+  (and 
+       (equality-benchmark1 n1)
+       ))
+
+(define (main)
+  (let* ((input0 100)
+         (input1 1) ;100)
+         (input2 8)
+         (input3 1000)
+         (input4 2000)
+         (input5 5000)
+         (output #t)
+         (s5 (number->string input5))
+         (s4 (number->string input4))
+         (s3 (number->string input3))
+         (s2 (number->string input2))
+         (s1 (number->string input1))
+         (s0 (number->string input0))
+         (name "equal"))
+    (run-r7rs-benchmark
+     (string-append name ":" s0 ":" s1 ":" s2 ":" s3 ":" s4 ":" s5)
+     1
+     (lambda ()
+       (equality-benchmarks (hide input0 input0)
+                            (hide input0 input1)
+                            (hide input0 input2)
+                            (hide input0 input3)
+                            (hide input0 input4)
+                            (hide input0 input5)))
+     (lambda (result) (eq? result #t)))))
+
+;;; The following code is appended to all benchmarks.
+
+;;; Given an integer and an object, returns the object
+;;; without making it too easy for compilers to tell
+;;; the object will be returned.
+
+(define (hide r x)
+  (call-with-values
+   (lambda ()
+     (values (vector values (lambda (x) x))
+             (if (< r 100) 0 1)))
+   (lambda (v i)
+     ((vector-ref v i) x))))
+
+;;; Given the name of a benchmark,
+;;; the number of times it should be executed,
+;;; a thunk that runs the benchmark once,
+;;; and a unary predicate that is true of the
+;;; correct results the thunk may return,
+;;; runs the benchmark for the number of specified iterations.
+
+(define (run-r7rs-benchmark name count thunk ok?)
+
+  ;; Rounds to thousandths.
+  (define (rounded x)
+    (/ (round (* 1000 x)) 1000))
+
+  (display "Running ")
+  (display name)
+  (newline)
+  (flush-output-port)
+  (let* ((j/s (jiffies-per-second))
+         (t0 (current-second))
+         (j0 (current-jiffy)))
+    (let loop ((i 0)
+               (result (if #f #f)))
+      (cond ((< i count)
+             (loop (+ i 1) (thunk)))
+            ((ok? result)
+             (let* ((j1 (current-jiffy))
+                    (t1 (current-second))
+                    (jifs (- j1 j0))
+                    (secs (inexact (/ jifs j/s)))
+                    (secs2 (rounded (- t1 t0))))
+               (display "Elapsed time: ")
+               (write secs)
+               (display " seconds (")
+               (write secs2)
+               (display ") for ")
+               (display name)
+               (newline))
+             result)
+            (else
+             (display "ERROR: returned incorrect result: ")
+             (write result)
+             (newline)
+             result)))))
+
+(main)