Brendan Gregg

JULY 4, 2021

## References I've reproduced the talk references below, so you can click on links: - [Gregg 08] Brendan Gregg, “ZFS L2ARC,” [link] Jul 2008 - [Gregg 10] Brendan Gregg, “Visualizations for Performance Analysis (and More),” [link] 2010 - [Greenberg 11] Marc Greenberg, “DDR4: Double the speed, double the latency? Ford, et al., “TCP

Performance 121

Performance Latency Hardware Storage 121

Brendan Gregg

MAY 8, 2021

Something like: It's called "[flying height]" or "fly height," and (from that reference) was about 5 nanometers for 2011 drives. From these outputs I try to determine if the problem is: - **The workload**: High-latency disk I/O is commonly caused by the workload applied. Note the sdb latencies range from 32 ms to over 2 seconds!

Performance 133

Performance Latency Speed Systems 133

All Things Distributed

MARCH 2, 2011

By Werner Vogels on 01 March 2011 10:00 PM. Japanese companies and consumers have become used to low latency and high-speed networking available between their businesses, residences, and mobile devices. Expanding the Cloud - Introducing the AWS Asia Pacific (Tokyo) Region. Comments ().

AWS 92

AWS Cloud Games Latency 92

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 103

Performance Latency Cache Virtualization 103

Brendan Gregg

JULY 4, 2021

## References I've reproduced the talk references below, so you can click on links: - [Gregg 08] Brendan Gregg, “ZFS L2ARC,” [link] Jul 2008 - [Gregg 10] Brendan Gregg, “Visualizations for Performance Analysis (and More),” [link] 2010 - [Greenberg 11] Marc Greenberg, “DDR4: Double the speed, double the latency? Ford, et al., “TCP

Performance 52

Performance Latency Hardware Storage 52

Alex Russell

MARCH 6, 2021

If those specs sound eerily familiar, it's perhaps because they're identical to 2016's $200USD Moto G4 , all the way down to the 2011-vintage 28nm SoC process node used to fab the chip's anemic, 2012-vintage A53 cores. Recall that single-core performance most directly translates into speed on the web. " package. How bad is it?

Performance 127

Performance Network Metrics Cache 127

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