SQL Performance

OCTOBER 14, 2020

I explained that when SQL Server optimizes a query involving derived tables, it applies transformation rules to the initial tree of logical operators produced by the parser, possibly shifting things around across what were originally table expression boundaries. Substitution/unnesting. ( SELECT TOP ( 9223372036854775807 ) *.

C++ 52

C++ Servers Code Efficiency 52

SQL Server According to Bob

DECEMBER 18, 2018

SQL Server relies on Forced-Unit-Access (Fua) I/O subsystem capabilities to provide data durability, detailed in the following documents: SQL Server 2000 I/O Basic and SQL Server I/O Basics, Chapter 2. Be sure to deploy SQL Server 2017 CU6 or newer for best data durability and performance results. “. The Back Story.

Servers 90

Servers Media Cache Storage 90

Percona

APRIL 12, 2023

Whereas many open source software offerings — like the community version of MySQL — use the GNU General Public License ( GPL ), MongoDB has been under the GNU Affero General Public License ( AGPL ) and more recently under the Server Side Public License ( SSPL ), introduced by MongoDB itself. looking out for MongoDB Inc.

Open Source 79

Open Source Programming Database Servers 79

SQL Performance

MARCH 20, 2020

We're mid-cycle between releases, where we're not yet hearing about any of the features planned for SQL Server vNext. In SQL Server 2016, STRING_SPLIT solved a long-missing gap in a language that, admittedly, was not intended for complicated string processing. And that is what I want to bring up today.

Database 109

Database Servers C++ AWS 109

SQL Performance

MAY 1, 2020

In a recent tip , I described a scenario where a SQL Server 2016 instance seemed to be struggling with checkpoint times. A SQL Server DBA myth a day: (15/30) checkpoint only writes pages from committed transactions. How It Works: When is the FlushCache message added to SQL Server Error Log? ADD EVENT sqlserver.

C++ 58

C++ Database Servers Storage 58

SQL Server According to Bob

JANUARY 26, 2017

My goal is to resolve mysteries about SQL Server I encounter but do this without going straight the source code first. The first case that helped me start this journey was asked by a MVP within the SQL Server community (his first name starts with Joey<g>). The question went something like this….

Servers 40

Servers Database Azure Cache 40

SQL Performance

JUNE 22, 2021

The FGCB_ADD_REMOVE latch protects a data structure called an FGCB, or File Group Control Block, and there will be one of these latches for each online filegroup of each online database in a SQL Server instance. DROP EVENT SESSION [ FGCB_ADDREMOVE ] ON SERVER ; END. CREATE EVENT SESSION [ FGCB_ADDREMOVE ] ON SERVER.

Servers 54

Servers Database Code Performance 54

SQL Performance

DECEMBER 9, 2020

Use the following code to run a test with base CTE cardinality of 2 (requires 5 additional levels of CTEs): DECLARE @low AS BIGINT = 1 , @high AS BIGINT = 100000000 ; WITH. I tested my solutions in SQL Server 2019 Enterprise edition. SQL Server chose row mode processing for all previously shown solutions by default.

C++ 114

C++ Servers Testing Processing 114

SQL Performance

MARCH 15, 2021

This time around, I want to talk about a feature included with SQL Server client tools that we should not be using these days – not just because it is deprecated but, more importantly, because it has the potential to completely take a server down: SQL Server Profiler. Not too long ago, something like this happened to us.

Servers 64

Servers Azure Best Practices Monitoring 64

Dynatrace

OCTOBER 28, 2021

As software performance degrades or fails, the chaos engineers’ findings enable developers to add resiliency into the code, so the application remains intact in an emergency. Chaos engineering matured at organizations such as Netflix, and gave rise to technologies such as Gremlin (2016) , becoming more targeted and knowledge-based.

Engineering 225

Engineering Entertainment Cloud Infrastructure 225

SQL Server According to Bob

JUNE 27, 2016

To some of you SQL Server On Linux is old news from various announcements made a couple of months ago. Yes, SQL Server runs on Linux! It was Jan 2015, in my previous supportability role, that I started looking at SQL Server on Linux. I proceeded to install an Ubuntu VM and the internal build of SQL Server on Linux.

Servers 40

Servers Games Azure Software Engineering 40

SQL Server According to Bob

JANUARY 5, 2017

Last March I moved from 22 years in SQL Server support to the SQL Server development team, working on SQL Server on Linux project and reporting to Slava Oks. As Slava highlights in his recent blog post , he also contacted me in early 2015 to assist with supportability of SQL Server on Linux. There are no burning secrets.

Servers 40

Servers Operating System C++ Software Engineering 40

SQL Server According to Bob

FEBRUARY 10, 2019

. · Failures occur from remote clients or sqlcmd executed directory on the server (/opt/mssql-tools/bin). SQL Server 2017 CU10 does not show behavior. · SQL Server 2017 CU12 exhibits the behavior. Server is a Superdome with lots of CPUs and RAM. Here is an example of a valid SQL Server login. – sqlclr.

Servers 40

Servers Network Database Systems 40

Percona

JANUARY 24, 2023

Some of the built-in features ( wal_compression ) have been there since 2016, and almost all backup tools do the WAL compression before taking it to the backup repository. Zstd can be chosen if the server load is not CPU bound because it can give us better compression at the expense of more CPU utilization.

Database 115

Database Benchmarking Open Source Latency 115

Percona

JUNE 4, 2023

In this blog, we’ll provide a comparison between MariaDB vs. MySQL (including Percona Server for MySQL ). Introduction: MariaDB vs. MySQL The goal of this blog post is to evaluate, at a higher level, MariaDB vs. MySQL vs. Percona Server for MySQL side-by-side to better inform the decision making process.

Open Source 52

Open Source Servers Storage Scalability 52

SQL Server According to Bob

APRIL 25, 2017

I recently visited a customer onsite and presented to them topics on SQL Server 2016. One question I got went like this “I’ve tried to restore a database on SQL Server using the WITH STATS option. That is a number in decimal which is the actual function pointer to the code to run the task. OK, this is very cool.

Servers 40

Servers Database Processing Virtualization 40

SQL Server According to Bob

APRIL 21, 2017

I recently visited a customer onsite and presented to them topics on SQL Server 2016. One question I got went like this “I’ve tried to restore a database on SQL Server using the WITH STATS option. That is a number in decimal which is the actual function pointer to the code to run the task. OK, this is very cool.

Servers 40

Servers Database Processing Virtualization 40

SQL Performance

MAY 29, 2019

It can be activated from SQL Server 2008 to 2014 inclusive using documented trace flag 610. From SQL Server 2016 onward, FastLoadContext is enabled by default ; the trace flag is not required. For more background, see the Data Performance Loading Guide and the Tiger Team notes on the behaviour changes for SQL Server 2016.

Cache 64

Cache Testing Servers Code 64

SQL Performance

AUGUST 11, 2021

Another is using a custom calculation that emulates the DATE_BUCKET function, which you can use in any version, edition, and flavor of SQL Server and Azure SQL Database. SQL Server Management Studio already has IntelliSense support, as shown in Figure 1: Figure 1: Intellisence support for DATE_BUCKET in SSMS. DATE_BUCKET.

Azure 139

Azure Code Database Servers 139

SQL Server According to Bob

JANUARY 28, 2018

Note: SQL Server can be a client using a linked server, allowing SQL Server to become an APP and/or an RM ). The application then uses the SQL Server client (SQL Server ODBC for this example) to establish a TDS based connection to the target SQL Server (local or remote.). Local Host Name. The olehlp!

Servers 40

Servers Azure Engineering Java 40

SQL Performance

JUNE 9, 2021

Note that the CREATE OR ALTER part was introduced in SQL Server 2016 SP1, so if you’re using an earlier version, you will need to work with separate CREATE VIEW and ALTER VIEW statements depending on whether the object already exists or not. You already saw the code with derived tables and CTEs earlier in the series. OrderYears.

Database 140

Database Code Design Development 140

Brendan Gregg

OCTOBER 8, 2018

bpftrace has most of DTrace's capabilities and more. ## bpftrace The prior work that led to [bpftrace] (aka BPFtrace) is discussed my earlier [DTrace for Linux 2016] post, which explains how the Linux kernel gained [eBPF]: the virtual machine that we're using to run tracing programs. bcc is powerful but laborious to program.

C++ 110

C++ Virtualization Programming Latency 110

Alex Podelko

OCTOBER 28, 2016

I am looking forward to share my thoughts on ‘Reinventing Performance Testing’ at the imPACt performance and capacity conference by CMG held on November 7-10, 2016 in La Jolla, CA. To do this, the tool should have the ability to add code to (or invoke code from) your script. – Cloud. – Agile.

Performance Testing 100

Performance Testing Technology Technology Testing 100

SQL Performance

AUGUST 14, 2019

Run the following code to create the Transactions table and populate it with sample data: SET NOCOUNT ON ; USE TSQLV5 ; -- [link]. SQL Server 2019 introduces batch mode on rowstore support, so you can get batch-mode processing even if there's no columnstore indexes present on the data. DROP TABLE IF EXISTS dbo. Transactions. (

Best Practices 108

Best Practices Servers Database Azure 108

SQL Performance

DECEMBER 9, 2020

Use the following code to run a test with base CTE cardinality of 2 (requires 5 additional levels of CTEs): DECLARE @low AS BIGINT = 1 , @high AS BIGINT = 100000000 ; WITH. I tested my solutions in SQL Server 2019 Enterprise edition. SQL Server chose row mode processing for all previously shown solutions by default.

C++ 61

C++ Servers Testing Processing 61

MachMetrics

JUNE 30, 2021

from wpostats, 2016 ). The factors that impact on LCP: Slow origin server response times Render-blocking JavaScript and CSS on page load Page Resource load times User side page rendering. Role of web servers in page load time –. You must have been suggested to choose a fast web server for better performance and reliable uptime.

Cache 78

Cache Speed Google Website 78

SQL Performance

SEPTEMBER 2, 2021

SQL Server 2016 brought us STRING_SPLIT , a native function that eliminates the need for many of the custom solutions we’ve needed before. I’ve written several articles about this function (and STRING_AGG, which arrived in SQL Server 2017) since this post was written: Performance Surprises and Assumptions : STRING_SPLIT().

C++ 59

C++ Servers Testing Database 59

The Morning Paper

SEPTEMBER 29, 2019

As the primary source of third-party JavaScript packages for the client-side, server-side, and other platforms, npm is the centrerpiece of a large and important software ecosystem. The change in the slope of the transitive dependencies line around 2016 is speculated to be due to the fallout from the left-pad incident. Threat models.

Code 76

Code Strategy Website Network 76

Brendan Gregg

SEPTEMBER 5, 2017

LTS (April 2016). It uses a Solaris Porting Layer (SPL) to provide a Solaris-kernel interface on Linux, so that unmodified ZFS code can execute. There's also a ZFS send/recv code path that should try to use the TASK_INTERRUPTIBLE flag (as suggested by a coworker), to avoid a kernel hang (can't kill -9 the process). amazon").

Virtualization 76

Virtualization AWS Engineering Hardware 76

CSS - Tricks

APRIL 1, 2021

The code for the site is available on GitHub for reference. It begins with retrieving the HTML from the server and converting this into the Document Object Model (DOM). I found a lot of value in the Coverage panel in DevTools because it will show just how much code is being used after everything’s downloaded.

Cache 92

Cache Social Media Media Website 92

SQL Performance

APRIL 20, 2021

This is the third in a five-part series taking a deep dive into the way SQL Server row mode parallel plans start executing. A reminder of the plan ( click to enlarge ): This is the first point in the process so far that an in-flight execution plan is available (SQL Server 2016 SP1 onward) in sys.dm_exec_query_statistics_xml.

C++ 98

C++ Processing Servers Cache 98

Enprowess

SEPTEMBER 28, 2021

React developers introduced Inferno in 2016 as an experiment to examine whether or not a library can improve the battery, performance, and UX of mobile apps. Inferno JS would be your best option, if you would like to build client and server-side interfaces with faster speeds, better performance, and isomorphic rendering. .

Open Source 52

Open Source Mobile Entertainment Virtualization 52

Rigor

JULY 2, 2019

As an example, we see that the preferred address to access the online edition of the New York Times is [link] (we received an HTTP response code of 200 when requesting the site). Rigor’s waterfall chart indicates that this address has been permanently moved (given that we received an HTTP response code of 301 ). Notes and Caveats.

Mobile 60

Mobile Traffic Google Latency 60

SQL Performance

MAY 7, 2019

I’m going to introduce you to wait statistics and explain how critical they are for troubleshooting workload performance in SQL Server. The execution of SQL Server’s internal code is done using a mechanism called threads. A scheduler has three basic ‘parts’: The processor , which has exactly one thread currently executing code.

Servers 40

Servers Azure Metrics Tuning 40

SQL Performance

APRIL 23, 2019

In SQL Server 2012, grouped (vector) aggregation was able to use parallel batch-mode execution, but only for the partial (per-thread) aggregate. SQL Server 2014 added the ability to perform parallel batch-mode grouped aggregation within a single Hash Match Aggregate operator. Introduction. instructions are available.

Servers 67

Servers Testing Metrics Storage 67

SQL Performance

SEPTEMBER 25, 2019

For modern versions of SQL Server, this essentially means that all key columns in an index spool must be of a comparable type, no more than 900 bytes* in total, with 64 key columns or fewer. Non-performance spools are used for many purposes within SQL Server, including: Halloween Protection. Optimizer Rules. Trace Flags and Hints.

Performance 104

Performance Cache Servers Education 104

Rigor

JANUARY 13, 2020

These are the bestsellers in the web performance field, including the good old Speed Up Your Site (2003) by Andy King; Steve Souders’ Even Faster Web Sites (2009) ; Ilya Grigorik’s High Performance Browser Networking (2013) ; Tammy Everts’ Time is Money (2016) ; and a handful of more recent publications. Using Webpagetest.

Performance 75

Performance Social Media Website Website Performance 75