Add dtrace + spall script

samples/pong/.gitignore

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+profile.dtrace
+profile.spall
+

samples/pong/trace.sh

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+#!/bin/bash
+
+# You will need dtrace2spall installed:
+#
+#   go install github.com/bvisness/dtrace2spall@latest
+#
+# You will also need `$(go env GOPATH)/bin` on your PATH.
+
+# Run DTrace and save to profile.dtrace
+sudo dtrace -n 'profile-997 /pid == $target/ { @[timestamp, pid, tid, ustack(100)] = count(); }' \
+    -x ustackframes=100 \
+    -o profile.dtrace \
+    -x aggsortkey -x aggsortkeypos=0 \
+    -c ./Pong.app/Contents/MacOS/orca
+# Convert to Spall and save to profile.spall
+cat profile.dtrace | dtrace2spall --freq 997 -o profile.spall --fields=_,pid,tid