The Morning Paper

JULY 4, 2019

The ‘controlled’ part is important here because given the scale and complexity of the environment under test, the only meaningful place to do this is in production with real users. a bug fix, configuration change, new feature, or A/B test). Netflix’s system is deployed on the public cloud as complex set of interacting microservices.

Latency 77

Latency Engineering Metrics Traffic 77

Brendan Gregg

JUNE 30, 2018

sounds like a homework exercise of purely academic value. This is a sanity test. If you test data transfers of a known size, and show their rate, you can do a simple sum to see the minimum throughput required, then compare that to network links. ### 3. If the benchmark reported 20k ops/sec, you should ask: why not 40k ops/sec?

Benchmarking 54

Benchmarking Latency Cache Network 54

Adrian Cockcroft

MARCH 17, 2020

There are many possible failure modes, and each exercises a different aspect of resilience. A learning organization, disaster recovery testing, game days, and chaos engineering tools are all important components of a resilient system. Memorial at Hawaiian native burial ground, Kapalua, Maui.

Healthcare 52

Healthcare Government Airlines Systems 52

Brendan Gregg

JUNE 29, 2018

sounds like a homework exercise of purely academic value. This is a sanity test. If you test data transfers of a known size, and show their rate, you can do a simple sum to see the minimum throughput required, then compare that to network links. ### 3. If the benchmark reported 20k ops/sec, you should ask: why not 40k ops/sec?

Benchmarking 40

Benchmarking Latency Cache Network 40

Adrian Cockcroft

NOVEMBER 11, 2019

There are many possible failure modes, and each exercises a different aspect of resilience. In the same way that we have moved from a few big software releases a year to continuous delivery of many small changes, we need to move from annual disaster recover tests or suffering when things actually break, to continuously tested resilience.

Latency 52

Latency Engineering Systems Hardware 52

The Morning Paper

JANUARY 23, 2020

1:18pm a key observation was made that an API call to populate the homepage sidebar saw a huge jump in latency. The process tracing exercise included: Examning IRC transcripts from multiple channels. During incident management, prefer peer review of any code changes to gain confidence as opposed to automated tests or other procedures.

Internet 53

Internet Internet Cache Engineering 53

Adrian Cockcroft

NOVEMBER 11, 2019

There are many possible failure modes, and each exercises a different aspect of resilience. In the same way that we have moved from a few big software releases a year to continuous delivery of many small changes, we need to move from annual disaster recover tests or suffering when things actually break, to continuously tested resilience.

Latency 53

Latency Engineering Systems Hardware 53

John McCalpin

JANUARY 22, 2018

There was no deep goal — just a desire to see the maximum GFLOPS in action. The exercise seemed simple enough — just fix one item in the Colfax code and we should be finished. Single-core testing with the same DGEMM routine showed maximum values of just under 72% of the nominal peak (about 90% of “adjusted peak”).

Latency 40

Latency Hardware Code Testing 40

The Agile Manager

DECEMBER 17, 2008

Traditional IT projects are mass economy-of-scale exercises: once development begins, armies of developers are unleashed. Traditionally in IT, our gatekeepers are typically several different waves of requirements and specification documents, then software, then test results, then a production event.

Latency 40

Latency Code Metrics Testing 40

O'Reilly Software

MARCH 7, 2018

This is mixing concerns and leads to code that becomes strongly coupled, monolithic, hard to write, hard to read, hard to evolve, hard to test, and hard to reuse. file , jms , test ; }. nextLong ()); }); In order to create a test datasource, we will randomly generate 1,000 orders using the generateOrders source. repeat ( "" ).

Transportation 72

Transportation Java Programming Architecture 72

The Netflix TechBlog

MARCH 6, 2019

Rerun a batch of replays We collect replays from actual MezzFS mounts in production, and we rerun large batches of replays for regression and performance tests. We parallelize rerun jobs with Titus , Netflix’s container management platform, which allows us to exercise many hundreds of replay files in minutes.

Media 214

Media Storage Processing Cache 214