abseil-cpp
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abseil-cpp | BDE | |
---|---|---|
54 | 7 | |
13,768 | 1,600 | |
3.1% | 0.7% | |
9.5 | 9.5 | |
4 days ago | about 14 hours ago | |
C++ | C++ | |
Apache License 2.0 | 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.
abseil-cpp
- Sane C++ Libraries
- Is Ada safer than Rust?
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Appending to an std:string character-by-character: how does the capacity grow?
Yeah, it's nice! And Abseil does it, IFF you use LLVM libc++.
https://github.com/abseil/abseil-cpp/blob/master/absl/string...
The standard adopted it as resize_and_overwrite. Which I think is a little clunky.
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Shaving 40% Off Google’s B-Tree Implementation with Go Generics
This may be confusing to those familiar with Google's libraries. The baseline is the Go BTree, which I personally never heard of until just now, not the C++ absl::btree_set. The benchmarks aren't directly comparable, but the C++ version also comes with good microbenchmark coverage.
https://github.com/google/btree
https://github.com/abseil/abseil-cpp/blob/master/absl/contai...
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“Once” one-time concurrent initialization with an integer
An implementation of call_once that accommodates callbacks that throw: https://github.com/abseil/abseil-cpp/blob/master/absl/base/c...
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[R] AlphaDev discovers faster sorting algorithms
I wouldn't say it's that cryptic. It's just a few bitwise rotations/shifts/xor operations.
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Deepmind Alphadev: Faster sorting algorithms discovered using deep RL
You can see hashing optimizations as well https://www.deepmind.com/blog/alphadev-discovers-faster-sort..., https://github.com/abseil/abseil-cpp/commit/74eee2aff683cc7d...
I was one of the members who reviewed expertly what has been done both in sorting and hashing. Overall it's more about assembly, finding missed compiler optimizations and balancing between correctness and distribution (in hashing in particular).
It was not revolutionary in a sense it hasn't found completely new approaches but converged to something incomprehensible for humans but relatively good for performance which proves the point that optimal programs are very inhuman.
Note that for instructions in sorting, removing them does not always lead to better performance, for example, instructions can run in parallel and the effect can be less profound. Benchmarks can lie and compiler could do something differently when recompiling the sort3 function which was changed. There was some evidence that the effect can come from the other side.
For hashing it was even funnier, very small strings up to 64 bit already used 3 instructions like add some constant -> multiply 64x64 -> xor upper/lower. For bigger ones the question becomes more complicated, that's why 9-16 was a better spot and it simplified from 2 multiplications to just one and a rotation. Distribution on real workloads was good, it almost passed smhasher and we decided it was good enough to try out in prod. We did not rollback as you can see from abseil :)
But even given all that, it was fascinating to watch how this system was searching and was able to find particular programs can be further simplified. Kudos to everyone involved, it's a great incremental change that can bring more results in the future.
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Backward compatible implementations of newer standards constructs?
Check out https://abseil.io. It offers absl::optional, which is a backport of std::optional.
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Best practice for cpp projects using CMake
As far as scientific studies go, I'm not sure if there are any that support the arguments of the linked proposal, but if you take a look at some of the most complex, large scale projects out there, you'll notice that they follow to a large extent the same structure as the one outlined in the above proposal. For instance, checkout the Google Chromium project, the AOSP projects, abseil, folly and many others. Of course, there will be exceptions so this is not a foolproof argument but I think it's interesting that projects of this scale have been designed this way.
BDE
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A Modern High-Performance Open Source Message Queuing System
Hi, one of the authors here. BlazingMQ depends on two other open source C++ libraries: https://github.com/bloomberg/bde and https://github.com/bloomberg/ntf-core. I believe documentation writer wanted to highlight that BlazingMQ does not depend on frameworks like ZooKeeper, etc.
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Announcing YOMM2 version 1.3.1
It would be easy to make the runtime use polymorphic allocators, one for the temporary objects created by update_methods, and another for the hash and dispatch tables. The first allocator could use the stack (like this), and the second a block in the BSS segment.
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Bloomberg finally opensourced memray —a new versatile memory profile for Python
I'm pretty sure they use C++ very extensively. They have their own C++ standard library for example. I'm not aware of them using FORTRAN or C. Do you have a reference for that?
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Eastl: An Alternative C++ Standard Library from Electronic Arts
Specifying your own allocator is like a main feature of bde from Bloomberg:
What are some alternatives?
Folly - An open-source C++ library developed and used at Facebook.
Boost - Super-project for modularized Boost
spdlog - Fast C++ logging library.
Qt - Qt Base (Core, Gui, Widgets, Network, ...)
EASTL - Obsolete repo, please go to: https://github.com/electronicarts/EASTL
MPMCQueue.h - A bounded multi-producer multi-consumer concurrent queue written in C++11
Seastar - High performance server-side application framework
Boost.Asio - Asio C++ Library
Yomm2 - Fast, orthogonal, open multi-methods. Solve the Expression Problem in C++17.