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. As a Xen guest, this profile was gathered using perf(1) and the kernel's software cpu-clock soft interrupts, not the hardware NMI.

Speed 126

Speed Java AWS Virtualization 126

All Things Distributed

APRIL 4, 2017

This enables customers to serve content to their end users with low latency, giving them the best application experience. In 2011, AWS opened a Point of Presence (PoP) in Stockholm to enable customers to serve content to their end users with low latency. In 2014 and 2015 respectively, AWS opened offices in Stockholm and Espoo, Finland.

AWS 116

AWS Airlines Latency Games 116

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. As a Xen guest, this profile was gathered using perf(1) and the kernel's software cpu-clock soft interrupts, not the hardware NMI.

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%. top(1) showed that only the Cassandra database was consuming CPU. As a Xen guest, this profile was gathered using perf(1) and the kernel's software cpu-clock soft interrupts, not the hardware NMI.

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. Hardware Past As Performance Prologue. Mind The Gap.

Performance 124

Performance Network Cache Metrics 124

Smashing Magazine

JANUARY 6, 2020

Estimated Input Latency tells us if we are hitting that threshold, and ideally, it should be below 50ms. Designed for the modern web, it responds to actual congestion, rather than packet loss like TCP does, it is significantly faster , with higher throughput and lower latency — and the algorithm works differently.

Performance 145

Performance Cache Network Metrics 145

Smashing Magazine

JANUARY 7, 2019

Estimated Input Latency tells us if we are hitting that threshold, and ideally, it should be below 50ms. On the other hand, we have hardware constraints on memory and CPU due to JavaScript parsing times (we’ll talk about them in detail later). On a middle-class mobile device, that accounts for 30-35 seconds for Time-To-Interactive.

Performance 103

Performance Cache Metrics Network 103