Time-to-fill for market orders by hour: how to measure it

[FXS London Scalper]

How long does a market order take from click to fill, and does it change by hour? For a 5-pip scalper it's worth knowing, and MT5 already records everything needed.

Method:

• The Journal tab logs a line when a request is sent and another when the deal executes, both with millisecond timestamps.
• Export a month of Journal logs (they live in the terminal's Logs folder as daily text files) and pair request and execution lines by order number.
• Group the delays by London hour and compute the median and the slowest 5%.

Also log your ping to the trade server. If ping stays at a couple of milliseconds while fill time rises, the extra delay is on the broker side.

What to expect, broadly: quiet hours fastest, the London open and the US data window slower, and news minutes with a long tail that can reach hundreds of milliseconds or more.

Why it matters: on ordinary minutes, tens of milliseconds change nothing for a 5-pip target. In the first 30 seconds after 08:00 London, a slow tail coincides with fast prices and wide spreads, which is a good argument for waiting a couple of minutes after the open.

If someone has a cleaner way to measure it than the Journal, I'd like to hear it.