Brendan Gregg

SEPTEMBER 25, 2021

A Cassandra database cluster had switched to Ubuntu and noticed write latency increased by over 30%. top(1) showed that only the Cassandra database was consuming CPU. This server is spending about a third of its CPU cycles just checking the time! What on Earth is Ubuntu doing that results in 30% higher CPU time!?

Speed 126

Speed Java AWS Virtualization 126

Brendan Gregg

SEPTEMBER 25, 2021

A Cassandra database cluster had switched to Ubuntu and noticed write latency increased by over 30%. top(1) showed that only the Cassandra database was consuming CPU. This server is spending about a third of its CPU cycles just checking the time! What on Earth is Ubuntu doing that results in 30% higher CPU time!?

Speed 40

Speed Java AWS Virtualization 40

SQL Performance

JULY 16, 2019

A close monitoring of the hardware enthusiast community, including many of the most respected hardware analysts and reviewers paints an even more dire picture about Intel in the server processor space. Despite all of this, Intel is not going to lose their entire server processor business any time soon. So, what has changed my mind?

Servers 46

Servers Hardware Architecture Retail 46

Brendan Gregg

SEPTEMBER 25, 2021

A Cassandra database cluster had switched to Ubuntu and noticed write latency increased by over 30%. top(1) showed that only the Cassandra database was consuming CPU. This server is spending about a third of its CPU cycles just checking the time! What on Earth is Ubuntu doing that results in 30% higher CPU time!?

Speed 52

Speed Java AWS Virtualization 52

Alex Russell

MARCH 6, 2021

Devices and networks have evolved too: Alex Russell @slightlylate An update on mobile CPUs and the Performance Inequality Gap: Mid-tier Android devices (~$300) now get the single-core performance of a 2014 iPhone and the multi-core perf of a 2015 iPhone. The cheapest (high volume) Androids perform like 2012/2013 iPhones, respectively.

Performance 124

Performance Network Cache Metrics 124

Smashing Magazine

JANUARY 6, 2020

Is it worth exploring tree-shaking, scope hoisting, code-splitting, and all the fancy loading patterns with intersection observer, server push, clients hints, HTTP/2, service workers and — oh my — edge workers? It used to provide an insight into how quickly the server outputs any data. What does it mean?

Performance 145

Performance Cache Network Metrics 145