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Faster remainders when the divisor is a constant: beating compilers and libdivide

Daniel Lemire

In some instances, libdivide can even be more efficient than compilers because it uses an approach introduced by Robison (2005) where we not only use multiplications and shifts, but also an addition to avoid arithmetic overflows. We also published our benchmarks for research purposes. I make my benchmarking code available.

C++ 279
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The Surprising Effectiveness of Non-Overlapping, Sensitivity-Based Performance Models

John McCalpin

The presentation discusses a family of simple performance models that I developed over the last 20 years — originally in support of processor and system design at SGI (1996-1999), IBM (1999-2005), and AMD (2006-2008), but more recently in support of system procurements at The Texas Advanced Computing Center (TACC) (2009-present).

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The Return of the Frame Pointers

Brendan Gregg

This technique saves two instructions in the prologue and epilogue and makes one additional general-purpose register (%rbp) available." 2005-2023: The winter of broken profilers However, the change was then applied to x86-64 (64-bit) as well, which had sixteen registers and didn't benefit so much from a seventeenth.

Java 145
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SQL Server I/O Basics Chapter #2

SQL Server According to Bob

As ​​ the ​​ administrator of a SQL Server 2005 installation, ​​ you will find that ​​ visibility into ​​ the ​​ SQL Server ​​ I/O ​​ subsystem ​​ has been ​​ significantly increased.

Servers 40
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Data Mining Problems in Retail

Highly Scalable

This approach can be expressed in more formal way by the following equation: where is the data available for analysis, is the space of a retailer’s actions and decisions, is an econometric model defined as a function of actions and data, and is the optimal strategy. This framework resembles the approach suggested in [JK98].

Retail 152