Issue:
You would like to know if AutoCAD takes advantage of multithreading, hyperthreading (Intel Xeon Processors), and multiple processors.
Solution:
Some components in AutoCAD since release 14 do handle multithreading (for example, the AutoLISP interpreter is a thread). AutoCAD Release 14 itself is not a thread-safe application and not really a multithreaded application. For AutoCAD 2000 and later, releases do have some support for dual processors and hyperthreading, but no more than two cores will be utilized. On dual-core processor systems, you will see significant increases in AutoCAD application performance, particularly for graphics and file I/O operations (see the WHIPTHREAD in the AutoCAD Help).
If you are using AutoCAD on a multi-processor system (i.e., more than two cores), you may see a slight performance improvement, but only as much as the operating system is taking advantage of the multiple processors.
An ARX application can make full use of multithreading as long as it is the only thread that communicates with AutoCAD . Again, this is because AutoCAD is not thread safe. Falling to do so will cause synchronization problems.
Note: Hyperthreading in Intel Xeon Processors enables a single processor to run two separate threads of software simultaneously. A single-core Xeon processor system with hyperthreading turned on will appear to the operating system as a dual processor system.
If you are using AutoCAD on a multi-processor system (i.e., more than two cores), you may see a slight performance improvement, but only as much as the operating system is taking advantage of the multiple processors.
An ARX application can make full use of multithreading as long as it is the only thread that communicates with AutoCAD . Again, this is because AutoCAD is not thread safe. Falling to do so will cause synchronization problems.
Note: Hyperthreading in Intel Xeon Processors enables a single processor to run two separate threads of software simultaneously. A single-core Xeon processor system with hyperthreading turned on will appear to the operating system as a dual processor system.

