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The Return of the Frame Pointers

Brendan Gregg

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. For a while I was promoting the use of Canonical's libc6-prof, which was libc6 with frame pointers. The actual overhead depends on your workload.

Java 145
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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. The computation of the remainder is nice, but I really like better the divisibility test. Can we do better?

C++ 279
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AWS EC2 Virtualization 2017: Introducing Nitro

Brendan Gregg

Hardware virtualization for cloud computing has come a long way, improving performance using technologies such as VT-x, SR-IOV, VT-d, NVMe, and APICv. The latest AWS hypervisor, Nitro, uses everything to provide a new hardware-assisted hypervisor that is easy to use and has near bare-metal performance. I'd expect between 0.1%

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SQL Server I/O Basics Chapter #2

SQL Server According to Bob

Copyright The information ​​ that is contained ​​ in this document represents the current view of Microsoft Corporation on the issues discussed as of the date of publication. The names of actual companies and products mentioned herein may be the trademarks of their respective owners.

Servers 40
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SQL Server On Linux: Forced Unit Access (Fua) Internals

SQL Server According to Bob

Testing shows that by using the Fua bit with the data, write request can reduce the I/O traffic by ~50% for a SQL Server, write-intensive workload. During my investigation, I traced, tested, reviewed, and instrumented the Linux kernel to understand the SQL Server I/O durability needs and associated impacts. Starting with the Linux 4.18

Servers 90
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AWS EC2 Virtualization 2017: Introducing Nitro

Brendan Gregg

Hardware virtualization for cloud computing has come a long way, improving performance using technologies such as VT-x, SR-IOV, VT-d, NVMe, and APICv. The latest AWS hypervisor, Nitro, uses everything to provide a new hardware-assisted hypervisor that is easy to use and has near bare-metal performance. I'd expect between 0.1%

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SQL 2016 – It Just Runs Faster Announcement

SQL Server According to Bob

My development collogues and I are starting a regular blog series, outlining the vast range of scalability improvements, allowing SQL Server 2016 to run across a wide array of hardware configurations, faster and better than previous releases of SQL Server. The following table is taken from an ASP.NET, session state cache, stress test.