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. It's an important vendor-neutral space to share the latest in technology.

Performance 110

Performance Latency Cache Virtualization 110

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., Ford, et al., “TCP on Upcoming Sapphire Rapids CPUs,” [link] Oct 2020 - [Liu 20] Linda Liu, “Samsung QVO vs EVO vs PRO: What’s the Difference?

Performance 140

Performance Latency Hardware Storage 140

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. It was a great privilege. 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., Ford, et al., “TCP on Upcoming Sapphire Rapids CPUs,” [link] Oct 2020 - [Liu 20] Linda Liu, “Samsung QVO vs EVO vs PRO: What’s the Difference?

Performance 52

Performance Latency Hardware Storage 52

Brendan Gregg

OCTOBER 8, 2018

more capable, and built from the ground up for the modern era of the eBPF virtual machine. Screenshot: tracing read latency for PID 181: # bpftrace -e 'kprobe:vfs_read /pid == 30153/ { @start[tid] = nsecs; } kretprobe:vfs_read /@start[tid]/ { @ns = hist(nsecs - @start[tid]); delete(@start[tid]); }'. eBPF does more. I wrote seeksize.d

C++ 110

C++ Virtualization Programming Latency 110

Alex Russell

MAY 9, 2022

This is a complex topic, but to borrow from a recent post , web performance expands access to information and services by reducing latency and variance across interactions in a session, with a particular focus on the tail of the distribution (P75+). Consistent performance matters just as much as low average latency.

Performance 86

Performance Latency Metrics Engineering 86

Brendan Gregg

SEPTEMBER 5, 2017

LTS (April 2016). I wrote about it in a previous post, [DTrace for Linux 2016]. 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. The hardest part on Linux is now done: kernel support. Hit Ctrl-C to end. ^C

Virtualization 76

Virtualization AWS Engineering Hardware 76