Read the article at: https://www.ebpf.top/post/en/bpf_rawtracepoint
1. Common Hook Types in eBPF Trace 2. BPF Rawtracepoint 2.1 Trace Performance Enhanced by 20% 2.2 Rawtracepoint Tracking Event Inspection and Quantity Statistics 2.3 Passing Parameter Changes 3. Example of Using rawtracepoint in BPF Programs 3.1 libbpf Library (Based on CO-RE) 3.2 Bpftrace Sample Code See Also 1. Common Hook Types in eBPF Trace eBPF allows tracing events in various categories within the trace domain as follows:
Kernel static trace points tracepoint/rawtracepoint/btf-tracepoint Refer to /sys/kernel/tracing/available_events Kernel dynamic trace points k[ret]probe, fentry/fexit (based on BTF) Kprobe /sys/kernel/tracing/available_filter_functions User-space static trace points USDT Viewing method: readelf -n or bpftrace tool bpftrace -l 'usdt:/home/dave/ebpf/linux-tracing/usdt/main:*' User-space dynamic trace: u[ret]probe, obtainable via nm hello | grep main Performance monitoring counters PMC perf_event This article will focus on rawtracepoint within kernel static tracing, concluding with practical code examples using the libbpf development library and bpftrace.……
Original Article: https://www.ebpf.top/post/bpfman_fedora_40
1. Background 2. Introducing bpfman 3. Standalone Deployment Process 4. Kubernetes Cluster Deployment Process 5. Summary Appendix: bpfman Single Machine Verification Development Environment Setup Code Download and Compilation of bpfman Test program management functionality 1. Background Fedora 40 proposes bpfman as the default program manager. The open-source project bpfman provides a deeper understanding of the eBPF runtime state, making it easier to manage eBPF programs (including loading, unloading, and viewing runtime status). This proposal requires approval from the Fedora Engineering Steering Committee (FESCo), but if successful, bpfman is likely to appear in Fedora 40 in April to enhance eBPF management.
So, what exactly is bpfman? This article will give you a brief introduction to bpfman and its working principles.
2. Introducing bpfman Originally named bpfd, bpfman is developed based on the Rust Aya library, using the Rust programming language.……
Article address: https://www.ebpf.top/post/network_and_bpf_2024
1. eBPF 1.1 Exponential Growth of eBPF 1.2 eBPF Application Market 1.3 Wider Application of eBPF in Mobile Devices 1.4 Risks of eBPF Abuse 2. Observability 2.1 The Most Popular Topic: Observability 2.2 Reducing Observability Overhead 2.3 Context-Aware Kubernetes Workloads 2.4 AI-Assisted Network Troubleshooting 3. Networking 3.1 Container Networking Performance Matching Host Networking Performance 3.2 Transformation in the Networking Industry 3.3 Cilium in Home Environments 3.4 Network Operators Seeking LLM Help - Not All Roses 4. Cloud Native 4.1 Kubernetes Users Pushing Back on Complexity 4.2 IPv6-Only Kubernetes Clusters Becoming More Common 4.3 Rapid Growth of WSAM 4.4 The Not-to-Be-Forgotten Heterogeneous Networks 4.5 The Challenges of Platform Engineering and Network Growth In early 2024, Nico Vibert, Senior Sales Engineer at Isovalent, made some predictions about networks and eBPF. Here, we’ll briefly outline some important conclusions, mainly related to eBPF/Cilium/cloud-native/network/observability, and security areas.……
Program Framework (Skeleton) Combine the Open and Loader Stages Selective Attachment (Attach) Custom load and attach Multiple BPF handlers for the same event Map Reduce pre-allocation overhead Determining Map Size at Runtime Per-CPU Global Variables Note on accessing fields directly through pointers Conclusion Link to this article: https://www.ebpf.top/post/top_and_tricks_for_bpf_libbpf
Original article: https://www.pingcap.com/blog/tips-and-tricks-for-writing-linux-bpf-applications-with-libbpf/
In the early days of 2020, when I was using the BCC tool to analyze our database’s performance bottlenecks and pulled code from GitHub, I unexpectedly found an extra libbpf-tools directory in the BCC project. I studied the articles on BPF Portability and BCC to libbpf Conversion and transformed the previously submitted bcc-tools into libbpf-tools based on the knowledge I had gained. Finally, I completed the conversion work for nearly 20 tools (see Why We Switched from BCC-Tools to libbpf-Tools for BPF Performance Analysis).
During this process, I was fortunate to receive a lot of help from Andrii Nakryiko (the person in charge of the libbpf + BPF CO-RE project).……
This article is available at: https://www.ebpf.top/post/lsm_bpf_intro
1. Background on Security 2. General Framework of Kernel Security Policy Module LSM 2.1 Introduction to LSM Framework 2.2 Architecture of LSM 2.3 Hook Functions in LSM 3. LSM BPF 3.1 BCC Practice 3.2 libbpf-bootstrap Framework Practice 4. Summary 5. Appendix: Process of Finding LSM Hot Patch Kernel Vulnerabilities Monitoring Hook Points 1. Background on Security Internationally, computer security is summarized by three main characteristics: Confidentiality, Integrity, and Availability (CIA).
Confidentiality means that data is not visible to unauthorized individuals. Integrity refers to information not being altered during storage or transmission. Availability implies that one’s devices can be used when needed. There are roughly four methods that computer systems employ to address security challenges: isolation, control, auditing, and obfuscation.
Access control involves controlling access, representing the subject’s actions on objects. Access control primarily involves defining subjects and objects, operations, and setting access policies.……
Article link: https://www.ebpf.top/en/post/cisco_and_isovalent
On December 21, 2023, Thomas Graf, CTO & Co-founder of Isovalent, and Tom Gillis, Senior Vice President and General Manager of Cisco’s Security Business Group, announced on their respective company websites Cisco’s plan to acquire Isovalent. The acquisition price was not disclosed by either party. Following the completion of the acquisition, the Isovalent team is set to join Cisco’s Security Business Group, with the acquisition expected to be finalized in the third quarter of the 2024 fiscal year. Cisco has a history with Isovalent, having participated in Isovalent’s $29 million Series A funding at the end of 2020. Subsequently, in 2022, Cisco, along with Microsoft, Google, and other companies, added $40 million in the Isaolvent’s Series B funding.
Cisco aims to enhance its capabilities in multi-cloud networking and security through this acquisition. The collaboration between Cisco and Isovalent will leverage the power of Cilium’s open-source technology to create uniquely advanced multi-cloud security and networking functionalities, aiding customers in simplifying and accelerating their digital transformation journey.……
Read more at: https://www.ebpf.top/post/cpu_io_wait
1. Definition of I/O Wait 2. Test and Verification 3. Further Clarification on Disk Throughput and Processes with High I/O FrequencyAfter identifying process I/O wait conditions through the vmstat b column, we can further define them using iostat and iotop. 4. Analysis of Kernel CPU Statistics Implementation 5. Conclusion References 1. Definition of I/O Wait I/O Wait is a performance metric for a single CPU, indicating the idle time consumed when threads in the CPU dispatch queue (in the sleep state) are blocked on disk I/O. The CPU’s idle time is divided into truly idle time and time spent blocked on disk I/O. A higher CPU I/O Wait time indicates a possible bottleneck in the disk, causing the CPU to wait idle. If you find this definition a bit confusing, then please continue reading. I believe that after you read the testing and verification process in this article, your understanding of the above definition will be different.……
This article link: https://www.ebpf.top/en/post/ebpf_and_kernel_feature BPF kfuncs Bloom Filter Map: 5.16 Compile Once – Run Everywhere: Linux 5.17 [Kernel Space] bpf_loop() Helper Function: 5.17 BPF_LINK_TYPE_KPROBE_MULTI: 5.18 Dynamic Pointers and Type Pointers: 5.19 USDT: 5.19 BPF panic: 6.1 BPF Memory Allocator, Linked Lists: 6.1 User Ring Buffer: 6.1 User-defined linked list support: 6.2 User-defined rbtree support: 6.3 BPF Generic Iterator: 6.4 References: In 2022, the Linux kernel primarily released versions 5.16-5.19, 6.0, and 6.1, each introducing numerous new features for eBPF. This article briefly introduces these new features. For more in-depth information, please refer to the provided links. Overall, eBPF remains one of the most active modules in the kernel, with its functionality continuously evolving at a rapid pace. In a sense, eBPF is rapidly evolving towards a comprehensive kernel-state programmable interface. BPF kfuncs The BPF subsystem exposes many aspects of kernel……
This article is available at: https://www.ebpf.top/post/xdp_lb_demo
Author: Qiu Kang
Creating network environment SLB Cluster Routing NAT Mode Load Balancing Algorithms With the progress of eBPF, we can now deploy eBPF/XDP programs directly on regular servers to achieve load balancing, saving the need for dedicated machines for LVS deployment.
The previous article shared how to use xdp/ebpf to replace LVS for SLB. It adopted the independent machine deployment mode for SLB and loaded xdp program using bpftool and hardcoded configuration, which was version 0.1.
Version 0.2 modified the 0.1 version to a programmatic loading mode based on BPF skeleton. To experience this workflow easily without changing the overall deployment mode of version 0.1, you can check out https://github.com/MageekChiu/xdp4slb/tree/dev-0.2
Version 0.3 added support for dynamically loading SLB configurations in the form of configuration files and command-line parameters.
This article belongs to version 0.……
This article can be found at: https://www.ebpf.top/post/get_start_chatgpt
1. Introduction 2. Direct Experience 3. Official Account Registration 3.1 Account Registration 3.2 International SMS Verification 3.3 Testing the Effect 4. Summary References 1. Introduction ChatGPT is likely familiar to most people, sweeping the entire Internet and becoming a hot technology pursued by tech companies and a topic of great interest in the IT industry. ChatGPT is an AI chatbot program developed by OpenAI, launched in November 2022. ChatGPT is a large language model developed and trained by OpenAI, using a large language model based on the GPT-3.5 architecture and trained through reinforcement learning. It can generate high-quality text and performs well in various language tasks such as conversation generation, text summarization, text classification, etc.
Some say it’s a career killer for coders, a firefighter of inspiration for poets, a dream crusher for “town problem solvers”… Give it a simple command, and it can code, write poetry, or research papers.……