diff --git a/test/app/fiber.result b/test/app/fiber.result
index 4a094939f9c6..8eb506bd5e90 100644
--- a/test/app/fiber.result
+++ b/test/app/fiber.result
@@ -1469,6 +1469,16 @@ sum = 0
 fiber.top_enable()
 ---
 ...
+function isnan(num)\
+    return num ~= num\
+end
+---
+...
+-- Wait till a full event loop iteration passes, so that
+-- top() contains meaningful results.
+while isnan(fiber.top().cpu["1/sched"].instant) do fiber.yield() end
+---
+...
 a = fiber.top()
 ---
 ...
@@ -1504,9 +1514,9 @@ for k, v in pairs(a) do\
 end
 ---
 ...
-sum_inst
+sum_inst > 99 and sum_inst < 101 or sum_inst
 ---
-- 100
+- true
 ...
 -- not exact due to accumulated integer division errors
 sum_avg > 99 and sum_avg < 101 or sum_avg
@@ -1517,24 +1527,28 @@ tbl = nil
 ---
 ...
 f = fiber.new(function()\
-    for i = 1,1000 do end\
-    fiber.yield()\
-    tbl = fiber.top().cpu[fiber.self().id()..'/'..fiber.self().name()]\
+    local fiber_key = fiber.self().id()..'/'..fiber.self().name()\
+    tbl = fiber.top().cpu[fiber_key]\
+    while tbl.time == 0 do\
+        for i = 1,1000 do end\
+        fiber.yield()\
+        tbl = fiber.top().cpu[fiber_key]\
+    end\
 end)
 ---
 ...
-while f:status() ~= 'dead' do fiber.sleep(0.01) end
+while f:status() ~= 'dead' do fiber.yield() end
 ---
 ...
-tbl["average"] > 0
+tbl.average > 0
 ---
 - true
 ...
-tbl["instant"] > 0
+tbl.instant > 0
 ---
 - true
 ...
-tbl["time"] > 0
+tbl.time > 0
 ---
 - true
 ...
diff --git a/test/app/fiber.test.lua b/test/app/fiber.test.lua
index 38b85d554036..24cb8b4924a3 100644
--- a/test/app/fiber.test.lua
+++ b/test/app/fiber.test.lua
@@ -634,6 +634,14 @@ sum = 0
 -- gh-2694 fiber.top()
 fiber.top_enable()
 
+function isnan(num)\
+    return num ~= num\
+end
+
+-- Wait till a full event loop iteration passes, so that
+-- top() contains meaningful results.
+while isnan(fiber.top().cpu["1/sched"].instant) do fiber.yield() end
+
 a = fiber.top()
 type(a)
 -- scheduler is present in fiber.top()
@@ -652,19 +660,23 @@ for k, v in pairs(a) do\
     sum_avg = sum_avg + v["average"]\
 end
 
-sum_inst
+sum_inst > 99 and sum_inst < 101 or sum_inst
 -- not exact due to accumulated integer division errors
 sum_avg > 99 and sum_avg < 101 or sum_avg
 tbl = nil
 f = fiber.new(function()\
-    for i = 1,1000 do end\
-    fiber.yield()\
-    tbl = fiber.top().cpu[fiber.self().id()..'/'..fiber.self().name()]\
+    local fiber_key = fiber.self().id()..'/'..fiber.self().name()\
+    tbl = fiber.top().cpu[fiber_key]\
+    while tbl.time == 0 do\
+        for i = 1,1000 do end\
+        fiber.yield()\
+        tbl = fiber.top().cpu[fiber_key]\
+    end\
 end)
-while f:status() ~= 'dead' do fiber.sleep(0.01) end
-tbl["average"] > 0
-tbl["instant"] > 0
-tbl["time"] > 0
+while f:status() ~= 'dead' do fiber.yield() end
+tbl.average > 0
+tbl.instant > 0
+tbl.time > 0
 
 fiber.top_disable()
 fiber.top()