Table of Contents
Advertisement
the white paper "Developing Multi-threaded Applications: A
Platform Consistent Approach" (referenced in the Introduction
chapter).
•
When choosing between different primitives to implement a
synchronization construct, using Intel Thread Checker and Thread
Profiler can be very useful in dealing with multi-threading
functional correctness issue and performance impact under
multi-threaded execution. Additional information on the capabilities
of Intel Thread Checker and Thread Profiler are described in
Appendix A.
Table 7-1 is useful for comparing the properties of three categories of
synchronization objects available to multi-threaded applications.
Table 7-1
Properties of Synchronization Objects
Operating System
Synchronization
Characteristics
Objects
Cycles to
Thousands or Tens
acquire and
of thousands cycles
release (if there
is a contention)
Power
Saves power by
consumption
halting the core or
logical processor if
idle
Scheduling and
Returns to the OS
context
scheduler if
switching
contention exists
(can be tuned with
earlier spin loop
count)
Ring level
Ring 0
Multi-Core and Hyper-Threading Technology
Light Weight User Syn-
chronization
Hundreds of cycles
Some power saving if
using PAUSE
Does not return to the
OS scheduler
voluntarily
Ring 3
7
Synchronization
Object based on MON-
ITOR/MWAIT
Hundreds of cycles
Saves more power
than PAUSE
Does not return to the
OS scheduler
voluntarily
Ring 0
7-21
Advertisement
Table of Contents
