Joe Williams joewilliams

ARM’s Scalable Vector Extensions: A Critical Look at SVE2 For Integer Workloads

Scalable Vector Extensions (SVE) is ARM’s latest SIMD extension to their instruction set, which was announced back in 2016. A follow-up SVE2 extension was announced in 2019, designed to incorporate all functionality from ARM’s current primary SIMD extension, NEON (aka ASIMD).

Despite being announced 5 years ago, there is currently no generally available CPU which supports any form of SVE (which excludes the [Fugaku supercomputer](https://www.fujitsu.com/global/about/innovation/

Do not enable QUIC on 1280-byte MTU IPv6 networks

Synopsis

QUIC requires transmission of at least 1350 bytes of UDP packets on IPv6 (and 1370 bytes on IPv4).
On Chrome/Chromium (and Vivaldi), if sending 1350-byte UDP packet fails on IPv6, fallback to HTTP/2 over TCP immediately occurs.

Implementation details on Chrome/Chromium (60.0.3112.55 on Vivaldi)

See the explanation in Japanese for the further details on the current implementation. Note well that this differs from the latest version of QUIC Internet-Draft: see draft-ietf-quic-transport-01 Section 8. Quote:

Internet Scale Services Checklist

A checklist for designing and developing internet scale services, inspired by James Hamilton's 2007 paper "On Desgining and Deploying Internet-Scale Services."

http://mvdirona.com/jrh/talksandpapers/jamesrh_lisa.pdf

Basic tenets

Does the design expect failures to happen regularly and handle them gracefully?
Have we kept things as simple as possible?

	// Package netconv provides utilities to convert between types in packages net
	// and netip.
	package netconv

	import (
	"net"
	"net/netip"
	)

	// PrefixToIPNet returns p as a *net.IPNet.