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The Speed of Time

Brendan Gregg

As a Xen guest, this profile was gathered using perf(1) and the kernel's software cpu-clock soft interrupts, not the hardware NMI. Measuring the speed of time Is there already a microbenchmark for os::javaTimeMillis()? I also shared setting the clocksource in my talks and in my 2015 [Linux tunables] post.

Speed 126
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USENIX LISA2021 Computing Performance: On the Horizon

Brendan Gregg

This was a chance to talk about other things I've been working on, such as the present and future of hardware performance. The video is on [youtube]: The slides are on [slideshare] or as a [PDF]: I work on many areas of performance, but recently I've had a lot of demand to talk about BPF. Ford, et al., “TCP

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The Speed of Time

Brendan Gregg

As a Xen guest, this profile was gathered using perf(1) and the kernel's software cpu-clock soft interrupts, not the hardware NMI. Measuring the speed of time Is there already a microbenchmark for os::javaTimeMillis()? I also shared setting the clocksource in my talks and in my 2015 Linux tunables post.

Speed 52
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The Speed of Time

Brendan Gregg

As a Xen guest, this profile was gathered using perf(1) and the kernel's software cpu-clock soft interrupts, not the hardware NMI. Measuring the speed of time Is there already a microbenchmark for os::javaTimeMillis()? I also shared setting the clocksource in my talks and in my 2015 [Linux tunables] post.

Speed 40
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Performance Testing with Open Source Tools – Myths and Reality

Alex Podelko

It was called Jellly at the time (mid 2015) but it was an early build of what OctoPerf would become. And when we started in 2015, JMeter was undoubtedly the best tool around. You have to remember this was in 2015, a lot has changed since, Gatling is definitely a stronger tool.

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AWS EC2 Virtualization 2017: Introducing Nitro

Brendan Gregg

Hardware virtualization for cloud computing has come a long way, improving performance using technologies such as VT-x, SR-IOV, VT-d, NVMe, and APICv. The latest AWS hypervisor, Nitro, uses everything to provide a new hardware-assisted hypervisor that is easy to use and has near bare-metal performance. I'd expect between 0.1%

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USENIX SREcon APAC 2022: Computing Performance: What's on the Horizon

Brendan Gregg

## References I've reproduced the references from my SREcon22 keynote 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?