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SQL Server I/O Basics Chapter #2

SQL Server According to Bob

KB sectors run on smaller sectors   14 System and sample databases   15 Determining the formatted sector size of database   15 What sector sizes does SQL Server support?

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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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How Parallel Plans Start Up – Part 1

SQL Performance

The fundamentals of row mode parallel execution haven’t changed since SQL Server 2005, so the following discussion is broadly applicable. The reservation guarantees SQL Server will remain around its configured maximum number of threads at all times, but the physical thread may not be immediately available from the thread pool.

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

SQL Server According to Bob

The operating system signals completion when the I/O stack finishes the request. Linux provides different system calls (syscall)/commands for asynchronous behavior. CSA ISO/IEC 9945-1:2005 (R2009) 3.375 Synchronized I/O Data Integrity Completion. Filesystem Type 1K-blocks Used Available Use% Mounted on. O_NONBLOCK.

Servers 90
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Linux Load Averages: Solving the Mystery

Brendan Gregg

Nowadays, the source code to old operating systems can also be found online. For everyone familiar with other operating systems and their CPU load averages, including this state is at first deeply confusing. **Why?** The oldest change in the entire Linux repo dates back to 2005, when Linus imported Linux 2.6.12-rc2,

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