SQL Performance

FEBRUARY 12, 2020

Here's the complete solution code: WITH C AS. ( ) SELECT id , col1 , MAX ( col1 ) OVER ( PARTITION BY grp ORDER BY id ROWS UNBOUNDED PRECEDING ) AS lastval FROM C ; Clearly, that's a lot more code and work compared to just saying IGNORE_NULLS. 10249 2017-07-10 10252 2017-07-11 10250 2017-07-12.

C++ 120

C++ Code Servers Database 120

Brendan Gregg

SEPTEMBER 5, 2017

Hit Ctrl-C to end. ^C C operation = 'read' usecs : count distribution 0 -> 1 : 0 | | 2 -> 3 : 0 | | 4 -> 7 : 4479 | *| 8 -> 15 : 1028 | | 16 -> 31 : 14 | | 32 -> 63 : 1 | | [.]. Many new tools can now be written, and the main toolkit we're working on is [bcc]. Tracing ZFS operation latency.

Virtualization 75

Virtualization AWS Engineering Hardware 75

SQL Performance

DECEMBER 11, 2019

WHERE NOT ( shippeddate = '20190102' ) ; This query returns the following output: orderid shippeddate -- -- 10249 2017-07-10 10252 2017-07-11 10250 2017-07-12. WHERE shippeddate IS NOT NULL ; This query generates the following output: orderid shippeddate -- -- 10249 2017-07-10 10252 2017-07-11 10250 2017-07-12.

Best Practices 117

Best Practices C++ Database Code 117

Dynatrace

SEPTEMBER 22, 2020

In 2017 we introduced the Dynatrace Partner Program , a three-tier program with sales and technical enablement. Earning c ompetencies . But b efore we get into the program details, I want to briefly share with you the insights , context , and drivers behind the introduction of the Competency P rogram. .

Programming 130

Programming Social Media Government Media 130

J. Paul Reed

JANUARY 24, 2017

I mentioned last week I’d have 2017 predictions for you… well, last week. So, what do I think 2017 will have in store for us? STABLE This prediction was originally published in a larger T echBeacon piece on 2017 DevOps predictions. But we’ll see this mechanism happen in 2017. Prediction #1: DevOps Will Be Declared 1.0-STABLE

DevOps 40

DevOps Engineering IoT C++ 40

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.

Monitoring 137

Monitoring Java C++ Strategy 137

Sutter's Mill

FEBRUARY 13, 2017

I don’t get to Europe very often apart from ISO C++ standards meetings, but this spring I’ve been able to accept invitations for two English-language European events in the last week of April. Tue-Thu Apr 25-27: High-Performance and Low-Latency C++ (Stockholm). Will C++ continue growing forever? Description.

Latency 48

Latency C++ Hardware Performance 48

The Netflix TechBlog

JULY 1, 2019

In a previous post , we described how our TV application consists of a C++ SDK installed natively on the device, an updatable JavaScript user interface (UI) layer, and a custom rendering layer known as Gibbon. those running the 2017 SDK?—?also The SNG files have a relatively large download size at ~1.5MB each.

Cache 166

Cache Design Testing Development 166

Percona

JANUARY 17, 2019

Here is a summary of the queries: Simple queries: select count(*) from ontime where flightdate > '2017-01-01'. sec) mysql> select count(*) from ontime where flightdate > '2017-01-01'; + -+ | count(*) | + -+ | 5660651 | + -+ 1 row in set (2 min 48.81 select avg(DepDelay/ArrDelay+1) from ontime.

Cache 72

Cache C++ AWS Airlines 72

Brendan Gregg

SEPTEMBER 5, 2021

I summarized this case study at [Kernel Recipes] in 2017 and have shared the full story here. ## 1. The other colors are yellow for C++, and red for other user-level code.) A microservice team asked me for help with a mysterious issue. They claimed that the ZFS file system was consuming 30% of CPU capacity.

Cache 141

Cache Cloud Code Java 141

SQL Performance

MAY 13, 2020

Customers AS C WHERE country = N'USA' ; Also here, the common assumption is that AS C is just a way to rename, or alias, the table Customers for the purposes of this query, starting with the logical query processing step where the name is assigned and onwards. C is what's known as a range variable. Orders AS O ON C.

C++ 143

C++ Code Design Servers 143

SQL Performance

SEPTEMBER 5, 2019

CREATE CLUSTERED COLUMNSTORE INDEX c ON #T WITH ( MAXDOP = 1 ) ; Run the following test queries against the new columnstore table: SELECT. c = COUNT_BIG ( * ) FROM #T AS T WHERE 1 = ( SELECT 1 ) -- Avoid trivial plan. You can skip the WHERE clauses if you are running SQL Server 2017. c1 = @Start + N.

Performance 81

Performance C++ Storage Servers 81

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

Brendan Gregg

SEPTEMBER 25, 2021

As (C) looked like a kernel rebuild, I started with (D) and (E). ## 5. I also rewrote this in C and called gettimeofday(2) directly: $ cat gettimeofdaybench.c. html [60s checklist]: /Articles/Netflix_Linux_Perf_Analysis_60s.pdf [re:Invent talk]: [link] [recommendation]: [link] [Nitro]: /blog/2017-11-29/aws-ec2-virtualization-2017.html

Speed 103

Speed Java AWS Virtualization 103

SQL Performance

OCTOBER 14, 2020

Here’s the attempted solution using a CTE: WITH C AS. ( Using our trick with the TOP filter in the inner query, you prevent the unnesting of the table expression, like so: WITH C AS. ( The following code returns only shippers with a maximum order date that is on or after January 1 st , 2018: USE PerformanceV5 ; WITH C AS. (

C++ 52

C++ Servers Code Efficiency 52

O'Reilly

MARCH 2, 2020

I don’t care what you call it, but large projects (a) are rarely successful, regardless of the methodology, because they (b) get overloaded with a lot of features that nobody needs but that sound good, and (c) forget what the customer or user really needs or wants. Key survey results: The C-suite is engaged with data quality.

Artificial Intelligence 22

Artificial Intelligence Software Architecture Programming C++ 22

O'Reilly Software

DECEMBER 31, 0001

2020 Apr 6 Off by Two 2019 May 12 f() vs f(void) in C vs C++ 2019 Jan 18 Finding Compiler Bugs With C-Reduce 2018 Oct 24 Booting a Custom Linux Kernel in QEMU and Debugging It With GDB 2018 Jun 2 Speeding Up Linux Kernel Builds With ccache 2017 Sep 5 GCC vs LLVM Q3 2017 Commit Rates and Active Developer Counts 2017 May 31 Running Clang-Tidy (..)

C++ 40

C++ Speed Development 40

SQL Server According to Bob

MAY 19, 2019

The reduction effort started when we shipped SQL Server 2017 ( [link].) SQL Server 2017. C++ template usage is an example of where COMDAT folding can shine. SQL Server 2017 uses function address comparisons which the enablement of COMDAT would break. SQL Server 2019. OPTIONAL HEADER VALUES. 20B magic # (PE32+).

IoT 61

IoT Servers Development Cache 61

Tech News Gather

NOVEMBER 22, 2022

The application world began to move forward after Google announced Kotlin as the new programming language for Android Apps at the 2017 I/O conference. Programmers are shifting to the more result-oriented and user-friendly Kotlin programming language due to its high compatibility with Java and Objective C and its excellent tooling support.

Development 52

Development Java Programming Google 52

Brendan Gregg

OCTOBER 28, 2017

For my first trip to Paris I gave the closing keynote at [EuroBSDcon 2017] on performance methodologies, using FreeBSD 11.1 Ctrl-C to end. ^C C Time (ms) per state (read script for info): COMM PID CPU RUNQ SLP USL SUS SWP LCK IWT YLD irq15: ata1 12 0 0 0 0 0 0 0 15024 0 [.] as an analysis target. Tracing scheduler events.

Systems 47

Systems Performance C++ Operating System 47

Adrian Cockcroft

JANUARY 29, 2023

Bill Kaiser of NewRelic published this blog in 2017 which goes some way towards what I’m talking about, but since then I have figured out a new way to interpret the data. > system.time(wait1 <- normalmixEM(waiting, mu=c(50,80), lambda=.5, What Is the Expected Distribution of Website Response Times? . >

Lambda 98

Lambda Latency Cache C++ 98

SQL Performance

MAY 1, 2020

availability_databases_cluster AS c ON s. group_id = c. Everything was on SQL Server 2017, so why was this setting so prevalent? AND is_read_only = 0. AND NOT EXISTS. ( ( SELECT 1 FROM sys. dm_hadr_availability_replica_states AS s INNER JOIN sys. role_desc = 'SECONDARY'. database_name = d.

C++ 58

C++ Database Servers Storage 58

Brendan Gregg

AUGUST 8, 2017

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. rc5-virtual (bgregg-xenial-bpf-i-0b7296777a2585be1) 08/01/2017 _x86_64_ (8 CPU) 10:15:51 PM UID PID %usr %system %guest %CPU CPU Command 10:16:51 PM 0 18468 2.85 3 tar termb$ iostat -x 60. [.]

Latency 111

Latency Metrics C++ Systems 111

SQL Server According to Bob

APRIL 24, 2018

I also started my career developing on UNIX systems with C++ and databases like Ingres. Last October we released SQL Server 2017 including support for Linux and Docker Containers. docker pull microsoft/mssql-server-linux:2017-latest. As I moved to other jobs, the PC was becoming very popular as was the Windows Operating System.

Servers 40

Servers Internet Internet Open Source 40

Randon ASCII

JANUARY 22, 2017

It’s also peculiar because log2f is a C Run-Time (CRT) function, which shouldn’t be supplied by Blink anyway. The symbol search order is unspecified by C++ and due to the One Definition Rule (ODR) the search order should not matter. defined inline log2 and log2f function PeriodicWave.cpp included MathExtra.h

C++ 56

C++ Code Systems Processing 56

Percona

JUNE 4, 2023

This blog post was originally published in November 2017 and was updated in June 2023. 3 GA 23 May 2017 10.2.6 Some features, like time-delayed replication that were present in MySQL since 2013, only make an appearance in MariaDB Server in 2017! In-development for MySQL 8.0 (now In-development for MySQL 8.0 (now

Open Source 52

Open Source Servers Storage Scalability 52

The Morning Paper

JANUARY 19, 2020

STELLA: report from the SNAFU-catchers workshop on coping with complexity , Woods 2017, Coping with Complexity workshop. Today’s choice is a report from a 2017 workshop convened with that title, and recommended to me by John Allspaw – thank you John! Take a trivial example with three components A, B, and C.

C++ 50

C++ Systems Software Software 50

Enprowess

NOVEMBER 2, 2021

Its first release was in May 2017 and was rarely used by developers, but it continues its speedy growth and becomes more and more popular in the developer community. Seamless integration : There is no need to Re-write code because it easily integrates with Swift or Objective C for iOS apps and Java for android. Flutter Overview.

Development 52

Development Social Media Mobile Code 52

Brendan Gregg

SEPTEMBER 5, 2021

I summarized this case study at Kernel Recipes in 2017; it is an old story that's worth resharing here. The other colors are yellow for C++, and red for other user-level code.) A microservice team asked me for help with a mysterious issue. They claimed that the ZFS file system was consuming 30% of CPU capacity.

Cache 52

Cache Cloud Java Code 52

The Morning Paper

NOVEMBER 21, 2019

This corpus contains every PlanOut script written between 3 August 2015 and 3 August 2017… Facebook also provided us with a corpus of manually specified contrasts that were used in the analysis of the experimentation scripts that were actually deployed.

Programming 52

Programming Internet Internet Design 52

SQL Server According to Bob

FEBRUARY 10, 2019

SQL Server 2017 CU10 does not show behavior. · SQL Server 2017 CU12 exhibits the behavior. – -c the control file. . · Failures occur from remote clients or sqlcmd executed directory on the server (/opt/mssql-tools/bin). Unpredictable when failures occur. · Non-yielding scheduler reports. · Health Session Information.

Servers 40

Servers Network Database Systems 40

Brendan Gregg

SEPTEMBER 25, 2021

As (C) looked like a kernel rebuild, I started with (D) and (E). ## 6. I also rewrote this in C and called gettimeofday(2) directly: $ cat gettimeofdaybench.c html [60s checklist]: /Articles/Netflix_Linux_Perf_Analysis_60s.pdf [re:Invent talk]: [link] [recommendation]: [link] [Nitro]: /blog/2017-11-29/aws-ec2-virtualization-2017.html

Speed 40

Speed Java AWS Virtualization 40

Brendan Gregg

SEPTEMBER 5, 2021

I summarized this case study at [Kernel Recipes] in 2017; it is an old story that's worth resharing here. ## 1. The other colors are yellow for C++, and red for other user-level code.) A microservice team asked me for help with a mysterious issue. They claimed that the ZFS file system was consuming 30% of CPU capacity.

Cache 40

Cache Cloud Code Java 40

SQL Server According to Bob

JANUARY 29, 2017

Launch: lldb -c core.sqlservr.8917 FEB 1, 2017 UPDATE – CHANGE ACCEPTED. Using the -O command line parameter, when you start LLDB, indicates to LLDB to execute the command before the files are loaded. This lets you log information while loading the core dump. DLLs) during the target create action.

Servers 40

Servers Programming Open Source Media 40

SQL Performance

JANUARY 8, 2020

A much more elegant option is to use the CONCAT_WS function, which was introduced in SQL Server 2017. ( 1 , 'A' , 100.00 ) , ( 2 , 'B' , 200.00 ) , ( 3 , 'C' , NULL ) ; Notice that contacts 1 and 2 have applicable hourly rates, and contact 3 doesn't, so its hourly rate is set to NULL. 3 C NULL 4 D 150.00

Design 65

Design C++ Code Database 65

O'Reilly

MARCH 23, 2023

The LLaMA source code has been ported to C++ , and a small version of the model itself (7B) has been leaked to the public, yielding a model that can run on laptops. All of these models are based on a technology called Transformers , which was invented by Google Research and Google Brain in 2017.

Google 128

Google Open Source Programming Code 128

Randon ASCII

APRIL 17, 2018

It shouldn’t take much C# code to make an app that monitors the root of all drives, using buffer sizes that start small and gradually get larger. The source code for the C# FileSystemWatcher class can be found here. Another instance of this problem was hit in November 2017 and is described here. You know where to find me.

Monitoring 43

Monitoring C++ Code Processing 43