Brendan Gregg

SEPTEMBER 25, 2021

A Cassandra database cluster had switched to Ubuntu and noticed write latency increased by over 30%. This server is spending about a third of its CPU cycles just checking the time! I also shared setting the clocksource in my talks and in my 2015 [Linux tunables] post. 30.14% in the middle of the flame graph.

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%. This server is spending about a third of its CPU cycles just checking the time! I also shared setting the clocksource in my talks and in my 2015 [Linux tunables] post. 30.14% in the middle of the flame graph.

Speed 40

Speed Java AWS Virtualization 40

Brendan Gregg

SEPTEMBER 25, 2021

A Cassandra database cluster had switched to Ubuntu and noticed write latency increased by over 30%. This server is spending about a third of its CPU cycles just checking the time! I also shared setting the clocksource in my talks and in my 2015 Linux tunables post. 30.14% in the middle of the flame graph.

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

Smashing Magazine

JANUARY 11, 2021

In the end, it’s not the load events or server response times that define the experience, but the perception of how snappy the interface feels. It used to provide an insight into how quickly the server outputs any data. This knowledge will give you the best optimization target for ongoing efforts. What does it mean?

Performance 145

Performance Cache Media Metrics 145