How long are logs kept when using elmah in-memory logging?

How long are error log entries kept in memory when using Elmah In-Memory Logging? I have Elmah setup for a web service that uses that logger type.

There are no time limit - log entries will be kept until the application restarts. But there is a limit for number of stored entries: MemoryErrorLog from ELMAH 1.2 can remember up to 500 errors (15 by default).