diff --git a/scripts/profile-cool b/scripts/profile-cool
index d9f0bc3a8..52f8f4663 100755
--- a/scripts/profile-cool
+++ b/scripts/profile-cool
@@ -49,6 +49,6 @@ trap ' ' INT
 # note a) perf version 6.4.4 doesn't unmangle c++ names correctly for me, while 6.2.6 does
 perf record -F50 --call-graph dwarf,65528 --pid $kitpid
 # note b) perf version 5.14.21 is agonizingly slow without --no-inline, while 6.2.6 seems ok
-perf script --no-inline | stackcollapse-perf.pl > perf-$kitpid.log
-flamegraph.pl perf-$kitpid.log > perf-$kitpid.svg
+# merge all the background saves together as kitdbgsv
+perf script --no-inline | stackcollapse-perf.pl | sed -E -s "s/^kitbgsv[^;]+/kitbgsv/" | flamegraph.pl > perf-$kitpid.svg
 echo generated flamegraph output svg: perf-$kitpid.svg