New Intel tool to help debug apps for hyperthreading

Intel Corp. released a new software tool aimed at helping developers check for bugs in multithreaded software applications for use on processors with Intel’s hyperthreading technology.

A single user license for Intel Thread Checker costs US$1,198, and is available for download on Intel’s Web site as of Tuesday, the company said in a press release. It is designed to be used when bug-checking a multithreaded application, or a software program that throws multiple instruction streams at a processor simultaneously.

Normal processors execute streams of instructions sequentially, but hyperthreading allows a processor to execute different instruction streams simultaneously, according to Intel.

It takes advantage of unused execution units in the processor, said Dean McCarron, principal analyst at market research firm Mercury Research Inc. in Cave Creek, Ariz. Execution units are part of the hardware of the processor, and complete the operations specified in the instruction stream.

Some instruction streams are dependent on the stream preceding it, while some streams can be processed independently, he said. A processor equipped with hyperthreading can detect when an execution unit is not being used because the processor is waiting for a series of dependent streams to finish executing through another unit. It then assigns an independent thread to the unused unit, speeding up the overall process.

Multithreaded applications benefit from this technology, which fools the operating system into thinking the system has two processors and ordering the application to send more instruction streams to the processor, McCarron said. An example of a multithreaded application is Adobe Systems Inc.’s Photoshop, which requires an instruction stream to run the overall application, and another to handle the graphics manipulation, he said.

Users who wish to take advantage of Intel’s processors with hyperthreading technology, such as the 3.06GHz Pentium 4 processor and several Xeon server processors, need to purchase multithreaded software or recode single-threaded applications into multiple threads, McCarron said.

Developers using Intel Thread Checker will be able to identify specific lines of code that contain errors, allowing them to more quickly repair software bugs that are causing threading errors, Intel said. It automatically classifies bugs as serious errors or issues warnings for suspect code, and shows variable, source line, and call stack information, the Santa Clara, Calif., company said.

The tool can be downloaded at, and will be available through resellers sometime in the second quarter, Intel said. Users must be running Microsoft Corp.’s Windows XP or Windows 2000 operating system to use the tool, the company said.