SQL Performance

JUNE 14, 2019

However, a typical bug when converting the existing solution to one that applies the join is to leave the computation of the order count as COUNT(*), as shown in the following query (call it Query 1): SELECT C. Customers AS C LEFT OUTER JOIN Sales. Orders AS O ON C. GROUP BY C. ORDER BY C. Orders AS O ON C.

Best Practices 93

Best Practices C++ Database Processing 93

SQL Performance

APRIL 13, 2022

To test the performance of your solution, you’ll need to populate the table with larger volumes of sample data. L0 AS ( SELECT 1 AS c. numgroups AS INT = 1000 , @rowspergroup AS INT = 10000 , -- test with 1000 to 10000 here. My test machine has four logical CPUs, running SQL Server ® 2019 Enterprise.

C++ 136

C++ Strategy Testing Servers 136

The Netflix TechBlog

APRIL 17, 2019

Intel and Netflix announced their collaboration on a software video encoder implementation called SVT-AV1 on April 8, 2019. However, rav1e is written in Rust programming language, whereas an encoder written in C has a much broader base of potential developers. Added a unit tests framework based on Google Test.

Open Source 166

Open Source Scalability Speed Efficiency 166

The Morning Paper

SEPTEMBER 20, 2020

For example, think of the classic diamond pattern where A depends on B and C, and B and C both in turn depend on D, but there is no version of D that satisfies the constraints of both B and C. Of the 156 conflicts that Watchman predicted were likely to arise, 143 did so!

Monitoring 137

Monitoring Java C++ Strategy 137

Percona

MARCH 7, 2019

2019-02-22T18:26:25 Creating triggers. 2019-02-22T18:27:14 Created triggers OK. 2019-02-22T18:27:14 Copying approximately 4924071 rows. clients`: 94% 00:24 remain 2019-02-22T18:34:15 Copied rows OK. 2019-02-22T18:34:15 Analyzing new table. 2019-02-22T18:34:15 Swapping tables. Have realistic load tests.

C++ 98

C++ Traffic Servers Monitoring 98

Brendan Gregg

AUGUST 29, 2021

Hit Ctrl-C to end. ^C C msecs : count distribution 0 -> 1 : 83 | | 2 -> 3 : 20 | | 4 -> 7 : 0 | | 8 -> 15 : 41 | | 16 -> 31 : 1620 | * | 32 -> 63 : 8139 | *| 64 -> 127 : 176 | | 128 -> 255 : 95 | | 256 -> 511 : 61 | | 512 -> 1023 : 93 | |. Hit Ctrl-C to end. ^C 41 33681 ^C. Tracing block device I/O.

Cache 105

Cache C++ AWS Latency 105

SQL Performance

DECEMBER 9, 2020

In a comment to my article, Marcos Kirchner mentioned that he tested my solution with varying table value constructor cardinalities, and got different execution times for the different cardinalities. Testing different base table cardinalities is just one dimension to try. Let’s proceed to performance testing.

C++ 61

C++ Servers Testing Processing 61

The Morning Paper

JUNE 2, 2019

Developing machine learning models is no different from developing traditional software, in the sense that it is also a full life cycle involving design, implementation, tuning, testing, and deployment. So test sets used for CI have a ‘shelf-life’, after which they need to be refreshed. ci will raise an alarm (e.g.

C++ 60

C++ Strategy Testing Tuning 60

SQL Performance

MAY 11, 2022

I ran all the examples on SQL Server ® 2019 Developer, where batch-mode on rowstore is available. The following query, which I’ll refer to as Query 5, illustrates this technique: WITH C AS. ( Consider the following query, which I’ll refer to as Query 6: WITH C AS. ( I’ll remind you at the end. Figure 5: Plan for Query 5.

C++ 133

C++ Database Servers Code 133

HammerDB

JULY 17, 2019

From the previous post we now have source and binary copies of HammerDB for modification and test. The next step is to see if there is an Issue already created for the database we want to add or whether we should create one. > <mariadb> <connection> <maria_host>127.0.0.1</maria_host>

Database 40

Database C++ Testing Metrics 40

HammerDB

NOVEMBER 22, 2019

The HammerDB workload derived from TPC-C contains a feature to record the response times for the stored procedures that are run in the logfile. In testing with Excel 2013 we can simply give this file a.xls extension and open it. P50 866 1099 1455 1918.5 2318 2267 2271 2307 2315 2347 2299 2296 2301.5 We now have an option.

Virtualization 52

Virtualization C++ Testing 52

Randon ASCII

MARCH 30, 2020

My test builds took up to 6.2 I did my tests on an October 2019 version of Chromium’s code because that gave me the most flexibility about which build options to use. Wouldn’t it be nice if there was some way to test this? What of our jumbo build with up to five C++ files per compilation: python. count_costs.py

C++ 87

C++ Code Open Source Programming 87

HammerDB

JULY 8, 2019

HammerDB already has 2 interfaces with which to interface with the commands to build and test databases using the GUI interface or CLI. The following test script shows how this interaction can be done also including deliberate errors to demonstrate error handling. From HammerDB version 3.2 hammerdbws HammerDB Web Service v3.2

Benchmarking 40

Benchmarking Virtualization C++ Database 40

Brendan Gregg

AUGUST 29, 2021

100.00 ^C I'm looking at the r_await column in particular: the average wait time for reads in milliseconds. Hit Ctrl-C to end. ^C Hit Ctrl-C to end. ^C Smaller File Test For further confirmation, I collected the same outputs for a 32 Gbyte file upload. avg-cpu: %user %nice %system %iowait %steal %idle 14.81

Cache 40

Cache C++ AWS Systems 40

The Netflix TechBlog

OCTOBER 18, 2019

theme of the ML Platform meetup hosted at Netflix, Los Gatos on Sep 12, 2019. Contextual and Multi-armed Bandits enable faster and adaptive alternatives to traditional A/B Testing. Faisal Siddiqi Infrastructure for Contextual Bandits and Reinforcement Learning?—? Elliot talked about the three key components?—?a)

Infrastructure 126

Infrastructure Metrics Architecture Efficiency 126

The Netflix TechBlog

OCTOBER 18, 2019

theme of the ML Platform meetup hosted at Netflix, Los Gatos on Sep 12, 2019. Contextual and Multi-armed Bandits enable faster and adaptive alternatives to traditional A/B Testing. Faisal Siddiqi Infrastructure for Contextual Bandits and Reinforcement Learning?—? Elliot talked about the three key components?—?a)

Infrastructure 100

Infrastructure Metrics Architecture Efficiency 100

KeyCDN

OCTOBER 17, 2019

was released and approved in February of 2019 and is therefore ready to be used in production. While you can choose between liabom, rav1e, SVT-AV1 only the liabom seems to pass both the technical requirements and the “eye” test. The Future of AVIF AVIF is still in the early and experimental stages of existence in 2019.

Media 43

Media Internet Internet Speed 43

SQL Performance

OCTOBER 14, 2020

Then, you will probably want to continue reading this section and test the code that I use as I revisit key unnesting examples that I previously demonstrated with derived tables and convert them to use CTEs. Here’s the attempted solution using a CTE: WITH C AS. ( You won’t miss anything important that you haven’t read before.

C++ 140

C++ Servers Code Efficiency 140

The Symphonia

DECEMBER 7, 2018

We spent most of our time chatting to various folk about what they are doing with AWS now, and where they hope to proceed in 2019. Ruby, C++, and Rust are now Lambda languages directly supported by AWS. It was, as expected, another fascinating and stimulating week. Lambda, alone, had a treasure trove of updates: Python 3.7,

Lambda 40

Lambda Serverless AWS Blockchain 40

SQL Performance

FEBRUARY 10, 2021

I’ll do my testing in tempdb, enabling IO and TIME statistics: SET NOCOUNT ON ; USE tempdb ; SET STATISTICS IO , TIME ON ; The fastest solution from last month applies a join with a dummy table that has a columnstore index to get batch processing. Fastest solution so far. BatchMe ON 1 = 0. ORDER BY rownum ; GO.

C++ 124

C++ Servers Testing Code 124

Smashing Magazine

JULY 16, 2019

2019-07-16T14:30:59+02:00. 2019-07-16T14:35:52+00:00. Note: Windows users will also need Microsoft Visual C++ 14.0, which you can grab from “Microsoft Visual C++ Build Tools” over here. First you’ll need to make sure you have a c-compiler on your system. First of all, to start off, let’s install Scrapy.

Scalability 87

Scalability Website C++ Servers 87

HammerDB

JUNE 27, 2022

Also, when testing a database with a De-Witt clause, it was then possible to produce your own results without having to rely on a particular vendor to publish results of interest. Given the increasing importance of open source and the widespread use of HammerDB, the TPC adopted HammerDB in 2019 and now hosts the project on GitHub.

Benchmarking 62

Benchmarking Open Source C++ Cache 62

SQL Performance

OCTOBER 14, 2020

Then, you will probably want to continue reading this section and test the code that I use as I revisit key unnesting examples that I previously demonstrated with derived tables and convert them to use CTEs. Here’s the attempted solution using a CTE: WITH C AS. ( You won’t miss anything important that you haven’t read before.

C++ 52

C++ Servers Code Efficiency 52

Tasktop

OCTOBER 16, 2019

He casually mentioned that he found a really confusing test failure the other day that we should pair up on. An interesting aspect of our internal test infrastructure is that we do capture all trace logs during test runs (including HTTP requests, headers, generated test data, etc.) but only for the lifetime of a test run.

C++ 9

C++ Servers Testing Infrastructure 9

Brendan Gregg

SEPTEMBER 25, 2021

As (C) looked like a kernel rebuild, I started with (D) and (E). ## 5. There's also a test and println() in the loop to, hopefully, convince the compiler not to optimize-out an otherwise empty loop. This will slow this test a little.) I also rewrote this in C and called gettimeofday(2) directly: $ cat gettimeofdaybench.c.

Speed 126

Speed Java AWS Virtualization 126

Scalegrid

AUGUST 15, 2019

Read on to find out which is the best MongoDB GUI for you, updated for 2019, that contain these key features: A good visual editor to write and edit queries faster. Query Code for converting queries to five target language: Java, Python, C#, PHP, and JavaScript (Node.js). Autocompletion of queries. MongoDB Compass.

Database 40

Database Servers Monitoring Availability 40

Dynatrace

JULY 13, 2020

At the start, Docker was mainly use d by developers for testing purpose s , but the main challenge was to manage containers at scale in real-world production environments. . ? C ontainers cannot be used at their full potential when only on their own. Why are containers so hot?? . ? But how will you set up the communication?

Google 132

Google Ecommerce DevOps Cloud 132

Dynatrace

JULY 13, 2020

At the start, Docker was mainly use d by developers for testing purpose s , but the main challenge was to manage containers at scale in real-world production environments. . ? C ontainers cannot be used at their full potential when only on their own. Why are containers so hot?? . ? But how will you set up the communication?

Google 130

Google Ecommerce DevOps Cloud 130

Sutter's Mill

FEBRUARY 8, 2021

Otherwise, it’s “just an assertion”: As with an assertion, if a postcondition is false then it means there is a bug, likely right there inside the function on which the postcondition is written (or in the postcondition itself), because if prior contracts were well tested then likely this function created the first unexpected state. [2]

C++ 45

C++ Lambda Efficiency Code 45

Brendan Gregg

SEPTEMBER 25, 2021

As (C) looked like a kernel rebuild, I started with (D) and (E). There's also a test and println() in the loop to, hopefully, convince the compiler not to optimize-out an otherwise empty loop. This will slow this test a little.) I also rewrote this in C and called gettimeofday(2) directly: $ cat gettimeofdaybench.c

Speed 52

Speed Java AWS Virtualization 52

Brendan Gregg

SEPTEMBER 25, 2021

As (C) looked like a kernel rebuild, I started with (D) and (E). ## 6. There's also a test and println() in the loop to, hopefully, convince the compiler not to optimize-out an otherwise empty loop. This will slow this test a little.) I also rewrote this in C and called gettimeofday(2) directly: $ cat gettimeofdaybench.c

Speed 40

Speed Java AWS Virtualization 40

SQL Server According to Bob

DECEMBER 18, 2018

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

Servers Media Cache Storage 90

HammerDB

OCTOBER 12, 2018

This post complements the previous best practice guides this time with the focus on MySQL and MariaDB and achieving top levels of performance with the HammerDB MySQL TPC-C test. InnoDB is the storage engine that will deliver the best OLTP throughput and should be chosen for this test. . order by c.

Best Practices 40

Best Practices Scalability Performance C++ 40

Smashing Magazine

AUGUST 9, 2019

2019-08-09T12:30:59+02:00. 2019-08-09T12:36:17+00:00. You can also view this here , where real network conditions will be applied, so you can run your own tests. We’ll use this expander UI component as our test subject when developing the SASS-oriented solution for handling unused CSS. Luke Harrison. Large preview ).

Performance 94

Performance C++ Media Website 94

HammerDB

OCTOBER 18, 2019

Well its difficult to be entirely sure however the tests have all the characteristics of tests observed previously where the CPUs are running in powersave mode. So lets take an Ubuntu system with Platinum 8280 CPUs with the following Ubuntu OS, reboot and check the CPU configuration before running any tests. The answer is no.

Benchmarking 63

Benchmarking Performance Hardware C++ 63

SQL Server According to Bob

MAY 19, 2019

There are a bunch of folks with compiler, linker, SQL Server code, testing and other disciplines who provided input. Testing shows that locking mechanisms, such as spin locks, start to become saturated when shared across 8 to 12 CPUs and where the physics become a direct contributor to partitioned design. SQL Server 2019.

IoT 61

IoT Servers Development Cache 61

Smashing Magazine

APRIL 9, 2019

2019-04-09T12:30:59+02:00. 2019-04-29T18:34:58+00:00. I can test this out by putting that tag in a page, and then flipping to the Network tab in my browser tools to see that the file has been loaded. If A is in place, and you can make B happen, then a bug in C makes D possible. Understanding Subresource Integrity.

Website 57

Website Servers Code Best Practices 57