As of Solaris 11.3(SRU6) low-resolution in-memory timestamps are available through a new API. This is essentially a set of timestamps in memory that are updated once per millisecond. Access to these timestamps should be very quick and so may be a good replacement for the low-resolution time API's in the VM that currently use gettimeofday.

Need to investigate how these new calls perform and if they are suitable replacements.