Are you processing the files you found in any way you don't show us? I'm still looking for an explanation for the measly speedup you're experiencing. Time for a reality check. How long does it take to run this?

find /where/the/secret/files/are -name secret.file 1>secret-files.dat 
+2>/dev/null
[download]

Also, how stressed is the server? Please try to find out about the CPU-load and the IO-load.