Brendan Gregg

SEPTEMBER 25, 2021

A Cassandra database cluster had switched to Ubuntu and noticed write latency increased by over 30%. CLI tools The Cassandra systems were EC2 virtual machine (Xen) instances. 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

The Netflix TechBlog

NOVEMBER 9, 2022

While we understand it’s virtually impossible to achieve a linear increase in throughput as the number of vCPUs grow, a near-linear increase is attainable. What’s worse, average latency degraded by more than 50%, with both CPU and latency patterns becoming more “choppy.” This was our starting point for troubleshooting.

Hardware 363

Hardware Cache Performance Latency 363

Brendan Gregg

FEBRUARY 28, 2023

My personal opinion is that I don't see a widespread need for more capacity given horizontal scaling and servers that can already exceed 1 Tbyte of DRAM; bandwidth is also helpful, but I'd be concerned about the increased latency for adding a hop to more memory. Ford, et al., “TCP

Performance 52

Performance Latency Cache Virtualization 52

Brendan Gregg

JULY 4, 2021

It's an exciting time for developments in computer performance, not just for the BPF technology (which I often [write about]) but also for processors with 3D stacking and cloud vendor CPUs (e.g., This was a chance to talk about other things I've been working on, such as the present and future of hardware performance. Ford, et al., “TCP

Performance 52

Performance Latency Hardware Storage 52

Dotcom-Montior

NOVEMBER 11, 2020

those resources now belong to cloud providers, such as AWS Lambda, Google Cloud Platform, Microsoft Azure, and others. Again, the benefit being that the code within your containers or virtual machines is managed by the cloud provider. When code isn’t in use, the cloud providers typically throttle it all the way down.

Serverless 57

Serverless Monitoring Lambda Latency 57

VoltDB

JUNE 1, 2017

It was – like the hypothetical movie I describe above – more than a little bit odd, as you could leave a session discussing ever more abstract layers of virtualization and walk into one where they emphasized the critical importance of pinning a network interface to a specific VM for optimal performance.

Hardware 56

Hardware Latency Virtualization Cloud 56

Dotcom-Montior

NOVEMBER 24, 2021

With the rapid advancements in web application technologies, programming languages, cloud computing services, microservices, hybrid environments, etc., These systems can include physical servers, containers, virtual machines, or even a device, or node, that connects and communicates with the network. Concurrency. Heterogeneity.

Systems 74

Systems Monitoring Hardware Network 74

VoltDB

JUNE 1, 2017

It was – like the hypothetical movie I describe above – more than a little bit odd, as you could leave a session discussing ever more abstract layers of virtualization and walk into one where they emphasized the critical importance of pinning a network interface to a specific VM for optimal performance.

Hardware 40

Hardware Latency Virtualization Cloud 40

HammerDB

OCTOBER 23, 2023

The data shows a scripted automated workload running a number of back to back tests each time with an increasing number of virtual users. Using MariaDB and analysing performance at a workload of 80 Virtual Users the first place we can look at is the information schema user_statistics to quantify the difference in the database traffic.

Benchmarking 62

Benchmarking Database Network C++ 62

All Things Distributed

JANUARY 23, 2012

Expanding the Cloud - The AWS Storage Gateway. Today Amazon Web Services has launched the AWS Storage Gateway, making the power of secure and reliable cloud storage accessible from customersâ?? The Amazon Virtual Private Cloud extends on-premises compute with all the power of AWS, making it elastic, scalable and highly reliable.

Storage 115

Storage AWS Virtualization Cloud 115

Brendan Gregg

SEPTEMBER 25, 2021

A Cassandra database cluster had switched to Ubuntu and noticed write latency increased by over 30%. CLI tools The Cassandra systems were EC2 virtual machine (Xen) instances. 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

Dynatrace

AUGUST 5, 2019

Across the board, the topics cloud migration, application modernization, breaking the monolith or hybrid cloud re-platforming have been a center point in many of our discussions with our joint enterprise customers. If you can answer all these questions fine – if not: get your own Dynatrace Trial and start installing OneAgents.

Cloud 31

Cloud Traffic Database Network 31

The Morning Paper

APRIL 14, 2019

The paper sets out what we can do in software given today’s hardware, and along the way also highlights areas where cooperation from hardware will be needed in the future. “ Preventing side-channel attacks between VMs hosted on public cloud infrastructure. Microarchitectural channels. Threat scenarios.

Hardware 44

Hardware Cache Latency Speed 44

Brendan Gregg

SEPTEMBER 25, 2021

A Cassandra database cluster had switched to Ubuntu and noticed write latency increased by over 30%. CLI tools The Cassandra systems were EC2 virtual machine (Xen) instances. 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

Abhishek Tiwari

JULY 12, 2018

These nodes and edges require a good amount of compute and storage which is typically distributed across a large number servers either running in the cloud or your own data center. A data pipeline is a software which runs on hardware. The software is error-prone and hardware failures are inevitable.

Latency 63

Latency Analytics Scalability Engineering 63

Brendan Gregg

AUGUST 8, 2017

Load averages are an industry-critical metric – my company spends millions auto-scaling cloud instances based on them and other metrics – but on Linux there's some mystery around them. They can be also useful when a single value of demand is desired, such as for a cloud auto scaling rule. I've never seen an explanation.

Latency 111

Latency Metrics C++ Systems 111

HammerDB

DECEMBER 5, 2020

A full understanding of why this is important requires some knowledge of the evolution of database hardware and software. For TPC-C this meant enough available spindles to reduce I/O latency and for TPC-H enough bandwidth for data throughput. This was both expensive and time consuming to configure.

C++ 40

C++ Benchmarking Virtualization Open Source 40

Brendan Gregg

SEPTEMBER 5, 2017

Here's some output from my zfsdist tool, in bcc/BPF, which measures ZFS latency as a histogram on Linux: # zfsdist. Tracing ZFS operation latency. Xen's biggest user is the Amazon EC2 cloud, which has over one million customers, and appears to be a custom version (it self identifies as version "3.4.3.amazon").

Virtualization 76

Virtualization AWS Engineering Hardware 76

Abhishek Tiwari

DECEMBER 27, 2017

Containerized data workloads running on Kubernetes offer several advantages over traditional virtual machine/bare metal based data workloads including but not limited to. portability between cloud and on-premises. In fact, if we go by current trends containerised microservices running on Kubernetes are the future.

Big Data 63

Big Data Storage Benchmarking Hardware 63

All Things Distributed

MARCH 11, 2016

This is a given, whether you are using the highest quality hardware or lowest cost components. When customers left the constraining, old world of IT hardware and datacenters behind, they started to develop systems with new and interesting usage patterns that no one had ever seen before. Primitives not frameworks.

AWS 144

AWS Hardware Retail Virtualization 144

Smashing Magazine

JANUARY 11, 2021

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 Media Metrics 145

All Things Distributed

JANUARY 18, 2012

DynamoDB is the result of 15 years of learning in the areas of large scale non-relational databases and cloud services. With Amazon DynamoDB, developers scaling cloud-based applications can start small with just the capacity they need and then increase the request capacity of a given table as their app grows in popularity.

Scalability 167

Scalability Database Ecommerce Latency 167