oloflarsson/CraftBukkit — comment on commit 6a7e0be681801102c44740c3b4094627100a5a43
File:  line 0
By oloflarsson:

I am however commenting out :
// MethodProfiler.b("checkLight"); // CraftBukkit - not in production code
this.s(k1 + this.random.nextInt(16), this.random.nextInt(this.height), j + this.random.nextInt(16));

So I don't know how well this will aggregation trick will run with that line non-disabled.
Perhaps the server will hickup a bit every second.
The real solution is comment out that line ^^ it is also a major CPU thief.