Event loop block

What happens#

Password hashing cost went from 10 to 12 rounds: 4× CPU per login.

How to prevent it#

The libuv thread pool, an Auth Provider, or a runtime without one event loop.

The postmortem opens the first of these that you do not own yet:

1. libuv thread pool
2. Managed identity

Engineering terms#

• Bcrypt
• Event loop
• Thread pool