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

Daniel Lemire

The division by a power of two ( / (2 N )) can be implemented as a right shift if we are working with unsigned integers, which compiles to single instruction: that is possible because the underlying hardware uses a base 2. uint64_t c = UINT64_C ( 0xFFFFFFFFFFFFFFFF ) / d + 1 ; // fastmod computes (n mod d) given precomputed c.

C++ 279
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Back-to-Basics Weekend Reading - A Decomposition Storage Model

All Things Distributed

Not everybody agreed that the "N-ary Storage Model" (NSM) was the best approach for all workloads but it stayed dominant until hardware constraints, especially on caches, forced the community to revisit some of the alternatives. The first practical modern implementation is probably C-Store by Stonebraker, et al.

Storage 72
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Linux Load Averages: Solving the Mystery

Brendan Gregg

TABLE OF EXP(-T/C) FOR T = 5 SEC. EXPFF: EXP 0.920043902 ;C = 1 MIN EXP 0.983471344 ;C = 5 MIN EXP 0.994459811 ;C = 15 MIN. The oldest change in the entire Linux repo dates back to 2005, when Linus imported Linux 2.6.12-rc2, This, too, was a dead end. rc2, and this change predates that. Yes, I'd say so.

Latency 111
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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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SQL Server On Linux: Forced Unit Access (Fua) Internals

SQL Server According to Bob

CSA ISO/IEC 9945-1:2005 (R2009) 3.375 Synchronized I/O Data Integrity Completion. Refer to the ISO documentation on file integrity for complete details: CSA ISO/IEC 9945-1:2005 (R2009) 3.376 Synchronized I/O File Integrity Completion. Linux may need similar utilities to control various hardware cache installations. Device Flush.

Servers 90