What is the test for a reasonable person to ask the court about a petition?

In my view, a "reasonable person," knowing that the court will send notice when a decision has been made, might refrain from asking the court about a petition until the petition has remained pending for an unusually long time. How long is unusually long depends, of course, "on the particulars ... of the measurer." In light of the "particulars" of a pro se prisoner, and perhaps thinking of our own docket, we have charitably allowed that even 21 months is "not an unusually long time to wait for a court's decision." Huizar v. Carey, 273 F.3d 1220, 1224 (9th Cir.2001).