Brendan Gregg

SEPTEMBER 25, 2021

A Cassandra database cluster had switched to Ubuntu and noticed write latency increased by over 30%. As a Xen guest, this profile was gathered using perf(1) and the kernel's software cpu-clock soft interrupts, not the hardware NMI. Software-based clocksources could fix those issues and provide accurate monotonically-increasing time.

Speed 126

Speed Java AWS Virtualization 126

The Netflix TechBlog

OCTOBER 19, 2020

If we had an ID for each streaming session then distributed tracing could easily reconstruct session failure by providing service topology, retry and error tags, and latency measurements for all service calls. Using simple lookup indices in Cassandra gives us the ability to maintain acceptable read latencies while doing heavy writes.

Infrastructure 233

Infrastructure Transportation Storage Open Source 233

Brendan Gregg

SEPTEMBER 25, 2021

A Cassandra database cluster had switched to Ubuntu and noticed write latency increased by over 30%. As a Xen guest, this profile was gathered using perf(1) and the kernel's software cpu-clock soft interrupts, not the hardware NMI. Software-based clocksources could fix those issues and provide accurate monotonically-increasing time.

Speed 40

Speed Java AWS Virtualization 40

Alex Russell

JANUARY 30, 2024

If you or your company are able to generate a credible worldwide latency estimate in the higher percentiles for next year's update, please get in touch. Lest we assume low-end means "short-lived", recent announcements regarding software support for these devices will considerably extend their impact.

Performance 90

Performance Network Mobile Speed 90

Alex Russell

APRIL 29, 2021

As an engineer on a browser team, I'm privy to the blow-by-blow of various performance projects, benchmark fire drills, and the ways performance marketing (deeply) impacts engineering priorities. With each team, benchmarks lost are understood as bugs. WebGL 2 launched for other platforms on Chrome and Firefox in 2017.

Media 145

Media Games Education Engineering 145

CSS - Tricks

APRIL 1, 2021

A 2017 study by Akamai says as much when it found that even a 100ms delay in page load can decrease conversions by 7% and lose 1% of their sales for every 100ms it takes for their site to load which, at the time of the study, was equivalent to $1.6 But those are things I did in image editing software.

Cache 92

Cache Social Media Media Network 92

John McCalpin

JANUARY 22, 2018

Introduction: In December 2017, my colleague Damon McDougall (now at AMD) asked for help in porting the fused multiply-add example code from a Colfax report ( [link] ) to the Xeon Phi x200 (Knights Landing) processors here at TACC. A peculiar throughput limitation on Intel’s Xeon Phi x200 (Knights Landing). cmpl $1000000000, %eax.

Latency 40

Latency Hardware Code Testing 40