From eea5f896780e07f7ca76685061d01e7be5a7abaa Mon Sep 17 00:00:00 2001 From: Lukas Larsson Date: Thu, 11 Sep 2014 18:26:26 +0200 Subject: erts, kernel: Add os:perf_counter function The perf_counter is a very very cheap and high resolution timer that can be used to timestamp system events. It does not have monoticity guarantees, but should on most OS's expose a monotonous time. A special instruction has been created for this counter to further speed up fetching it. OTP-12908 --- erts/preloaded/src/erts_internal.erl | 7 ++++++- 1 file changed, 6 insertions(+), 1 deletion(-) (limited to 'erts/preloaded/src/erts_internal.erl') diff --git a/erts/preloaded/src/erts_internal.erl b/erts/preloaded/src/erts_internal.erl index 84dedab930..c3a14d272d 100644 --- a/erts/preloaded/src/erts_internal.erl +++ b/erts/preloaded/src/erts_internal.erl @@ -45,7 +45,7 @@ -export([await_result/1, gather_io_bytes/2]). --export([time_unit/0]). +-export([time_unit/0, perf_counter_unit/0]). -export([is_system_process/1]). @@ -345,6 +345,11 @@ flush_monitor_messages(Ref, Multi, Res) when is_reference(Ref) -> time_unit() -> erlang:nif_error(undefined). +-spec erts_internal:perf_counter_unit() -> pos_integer(). + +perf_counter_unit() -> + erlang:nif_error(undefined). + -spec erts_internal:is_system_process(Pid) -> boolean() when Pid :: pid(). -- cgit v1.2.3