I’ve taken several attempts at parallelizing the LSD Radix Sort algorithm. This is a conceptual description of the latest attempt, which hopefully will work out well. My latest implementation of partially parallel version of LSD Radix Sort is performing very well, running at around 150 MegaInt32/sec implemented in C++ and nearly the same speed in […]

Read more "Parallel LSD Radix Sort"

C++ has included wonderful implementations of sorting algorithms over the years. Recently, with C++17 support for parallelism, sorting performance has skyrocketed by running on all of the available cores. The number of cores is predicted to grow in double-digit percentage per year, as competition between Intel and AMD heats up, giving these parallel algorithms wil […]

Read more "Faster C++ Sorting"

In graduate school one of my favorite topics to work on, with one of my graduate advisors (Dr. Robbins) at North Carolina State University (NCSU), was rendering stereoscopic (3-D) images. Several of these rendered images are posted below. The sample data comes from a scanning tunneling microscope and atomic force microscope, provided by the Material […]

Read more "Stereoscopic Imaging of Scanning Tunneling Microscope"

C# has several fundamental abstractions that make parallel programming possible. By splitting work across multiple processor cores, gains in performance can be quite significant. And, with AMD and Intel shipping processors with more and more cores, using all of these compute resources is critical. Some of C# parallel facilities are: Parallel.Invoke() which runs several functions […]

Read more "Parallel Divide-and-Conquer in C#"

In the initial blog I developed a faster checked summation of ulong arrays. By using integer operations when no arithmetic overflow is detected, helped propel performance 15X higher to 682 MegaUlongAdditions/second, for a typical case. However, the worst case was still as slow as summation of Decimal arrays – 48 MegaUlongAdditions/second. In this blog I’ll develop […]

Read more "Faster Checked Addition in C# (Part 2)"

Signed Integer Overflow Detection A similar method can be developed for summation of signed long arrays. When adding singed integers, arithmetic overflow is possible. In fact, arithmetic underflow is also possible – where adding two negatives results in a positive value. When adding two signed integers, four cases are possible: both positive both negative first […]

Read more "Faster Checked Signed Addition in C#"

In the blog “Faster Checked Addition in C#” we saw how to add numbers safely in C# without using the checked key work and without exceptions. This raised performance, since exceptions have quite a bit of overhead. In this blog, I’ll extend this idea to the data parallel SIMD/SSE instructions of Intel and AMD processors, […]

Read more "Checked SIMD/SSE Addition in C#"