hana
Seastar
hana | Seastar | |
---|---|---|
4 | 25 | |
1,640 | 8,034 | |
0.9% | 1.0% | |
5.1 | 9.7 | |
26 days ago | 5 days ago | |
C++ | C++ | |
Boost Software License 1.0 | Apache License 2.0 |
Stars - the number of stars that a project has on GitHub. Growth - month over month growth in stars.
Activity is a relative number indicating how actively a project is being developed. Recent commits have higher weight than older ones.
For example, an activity of 9.0 indicates that a project is amongst the top 10% of the most actively developed projects that we are tracking.
hana
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What are some C++ projects with high quality code that I can read through?
I like boost::hana. Wish I had more chances to use it at work.
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Simple `struct` static reflection system I use that tracks names, attributes (in my own code I also keep `constexpr` hashes of names) -- example gets fully inlined into `main()`
And then there's also the longstanding issue with default member initializers -- https://github.com/boostorg/hana/issues/409 -- which was a deal-breaker.The PROP system avoids this issue precisely by having the macro be as local as possible: the default member initializer is outside the macro. It does this while still letting you attach additional PropAttribs metadata (I'm not sure what additional metadata attachment looks like in Hana? haven't really tried). Default values and additional attributes are by and large quite more important to me in my use cases for reflection (component types in game ECS) than range syntax (everything I've needed and can think of needing is covered by for-each loop).
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cppa2z - Document modern C++ using unit tests
oh yes definitely, but I meant more the particular way I've done it so far - which has been to implement something similar to boost::hana::is_valid(), to make it take the least amount of boilerplate code per-use-case as possible: zero additional lines of code.
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C Implementation Challenge Replacing Stdmove And
Boost.Hana developers measured a very noticeable 15% decrease in compile time switching from a function call (admittedly -- with an additional layer of wrapper) to a raw static_cast. foonathan himself saw a little over a 5% decrease in his actual code. miki151 saw about a 3% improvement from replacing move with MOV only, ignoring forward. In a completely synthetic benchmark where I just generate a ton of move calls in a row, I get a little over 40% decrease in compile time.
Seastar
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I want to share my latest hobby project, dbeel: A distributed thread-per-core nosql db written in rust
I used glommio as the async executor (instead of something like tokio), and it is wonderful. For people wondering whether it's "good enough" or to use C++ and seastar (as I have thought about a lot before starting this project), take the leap of faith, it's fast - both in terms of run time and to code.
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How much reason is there to be multi-threaded in the k8s environment
b) It's proven now e.g Seastar, Glommio that the fastest way to run a multi-threaded application is to have one instance with one thread pinned per CPU core. Then to have fibers/lightweight threads on top handling all of the asynchronous code. Your approach of lots of instances is the slowest so there will be a ton of unnecessary thread context-switching.
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Are You Sure You Want to Use MMAP in Your Database Management System?
The most common example is DPDK [1]. It's a framework for building bespoke networking stacks that are usable from userspace, without involving the kernel.
You'll find DPDK mentioned a lot in the networking/HPC/data center literature. An example of a backend framework that uses DPDK is the seastar framework [2]. Also, I recently stumbled upon a paper for efficient RPC networks in data centers [3].
If you want to learn more, the p99 conference by ScyllaDB has tons of speakers talking about some interesting challenges.
[1] https://www.dpdk.org/.
[2] https://github.com/scylladb/seastar
[3] https://github.com/erpc-io/eRPC
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Why does Actix-web's handler not require Send?
I assume Tokio itself, see e.g monoio or glommio, but also Seastar for C++.
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What is DPDK library in C and how to learn it?
https://core.dpdk.org/supported/ lists supported nics. You're best just reading material from the dpdk website for figuring out roughly what it is. It is used for a lot of different goals. For most web C++ stuff it's mainly used because you can avoid round trips of data passing through the kernel and can reference network data without tons of copying. For an example check out the SeaStar framework, https://seastar.io/, which is under the hood of ScyllaDB.
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How Numberly Replaced Kafka with a Rust-Based ScyllaDB Shard-Aware Application
As this is a Kafka sub, this may be a good opportunity to mention that Redpanda is based on the same framework (seastar) as Scylla. The idea of sharding work to CPU cores turns out to apply very well to the Kafka data model, too!
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What are some C++ projects with high quality code that I can read through?
Seastar which is a thread per core runtime written by the Scylla devs thats used in both Redpanda and Scylla as the underlying runtime. https://github.com/scylladb/seastar
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Abstraction Is Expensive
ScyllaDB is, ironically, maybe one of the worst examples the author could have come up with for "abstraction" in the article.
If folks aren't familiar with their work/internal tech, go check out some of their repos like Seastar. They have some of the most talented systems programmers on the planet writing thin veneers over kernel and hardware API's to squeeze every ounce out of performance.
https://github.com/scylladb/seastar
I know it's beside the point, but I just had to share because I thought that was funny
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Modern JVM Multithreading • Paweł Jurczenko • Devoxx Poland 2021
I’ve seen frameworks for c++ (https://seastar.io/) and rust (https://github.com/actix/actix) which support what you’re describing out of the box.
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Who is using C++ for web development?
If you're interested in scaling and asynchronous programming in c++ I highly recommend you investigate the SeaStar application framework. You wouldn't build a web service with SeaStar, rather you would build the infrastructure that you would use to build the web service on top of. https://github.com/scylladb/seastar
What are some alternatives?
mio - Cross-platform C++11 header-only library for memory mapped file IO
Folly - An open-source C++ library developed and used at Facebook.
sml - C++14 State Machine library
glommio - Glommio is a thread-per-core crate that makes writing highly parallel asynchronous applications in a thread-per-core architecture easier for rustaceans.
dyno - Runtime polymorphism done right
Boost.Asio - Asio C++ Library
filesystem - An implementation of C++17 std::filesystem for C++11 /C++14/C++17/C++20 on Windows, macOS, Linux and FreeBSD.
Boost - Super-project for modularized Boost
doctest - The fastest feature-rich C++11/14/17/20/23 single-header testing framework
ffead-cpp - Framework for Enterprise Application Development in c++, HTTP1/HTTP2/HTTP3 compliant, Supports multiple server backends
robin-hood-hashing - Fast & memory efficient hashtable based on robin hood hashing for C++11/14/17/20
Qt - Qt Base (Core, Gui, Widgets, Network, ...)