meta/folly on Hacker News

…1.5, any growth factor below 2 has this property, how far below 2 regulates how quickly it happens, https://github.com/facebook/folly/blob/master/folly/docs/FBV... > it can be mathematically proven that a growth factor of 2 is rigorously…

comment by masklinn · 2021-04-14 · in Is WebAssembly magic performance pixie dust?

…Facebook's Folly library also provides type erasure functionality: https://github.com/facebook/folly/blob/master/folly/docs/Pol... Google's Abseil is full of type erasure: https://abseil.io/ Here is Adobe's C++ library for ty

comment by Kranar · 2021-03-13 · in An Object-Oriented Language for the '20s

…of the standard library you find is better than third party options. [1] https://abseil.io/ [2] https://github.com/facebook/folly [3] https://github.com/electronicarts/EASTL [4] https://www.boost.org/

comment by Kranar · 2021-03-09 · in “ISO obstructs adoption of standards by paywalling them”

…to say this exact same thing. Their executors are also more widely adopted and worth mentioning: https://github.com/facebook/folly/blob/master/folly/docs/Exe...

comment by stormbeard · 2021-01-01 · in Concurrencpp – A C++ concurrency library

Facebook's Folly provides something similar: https://github.com/facebook/folly/tree/master/folly/experime...

comment by loeg · 2021-01-01 · in Concurrencpp – A C++ concurrency library

…demonstrated that it works well for all of Facebook's load balancers, container systems, etc. [0] https://github.com/facebook/folly/blob/16d6394130b0961f6d688...

comment by alexgartrell · 2020-11-26 · in How io_uring and eBPF Will Revolutionize Programming in Linux

LLVM e.g. SmallVector: https://llvm.org/doxygen/SmallVector_8h_source.html Folly e.g. https://github.com/facebook/folly/tree/master/folly/logging , https://github.com/facebook/folly/blob/master/folly/concurre... ,…

comment by boryas · 2020-10-28 · in Ask HN: Good C++ code bases to read?

https://github.com/facebook/folly https://github.com/ziglang/zig

comment by latenightcoding · 2020-10-28 · in Ask HN: Good C++ code bases to read?

…https://github.com/scylladb/scylla https://github.com/catchorg/Catch2 https://github.com/facebook/folly

comment by gtirloni · 2020-10-27 · in Ask HN: Good C++ code bases to read?

…rseq library. The kernel will update the current CPU in a thread local on every context switch. [0] https://github.com/facebook/folly/blob/a590a0e559d0f1c7af442...

comment by terrelln · 2020-09-17 · in A Concurrency Cost Hierarchy

…and folly::f14:F14FastMap[2]. [1] https://abseil.io/about/design/swisstables [2] https://github.com/facebook/folly/blob/master/folly/containe...

comment by alexhutcheson · 2020-06-18 · in Cuckoo++ – High-Performance Hash Tables for Networking Applications (2017)

…and/or F14FastMap[2]. [1] https://abseil.io/docs/cpp/guides/container#hash-tables [2] https://github.com/facebook/folly/blob/master/folly/containe...

comment by alexhutcheson · 2020-04-24 · in Comparison of C++17, Go, and Java for a next-generation sequencing tool

…the library's contents. That said, the code is also reasonably well commented as well, for example: https://github.com/facebook/folly/blob/master/folly/Singleto... . So "read the code" is not terrible advice in this case either.

comment by shafte · 2020-04-17 · in Folly – Faceboook’s open source C++ library

…them more of a framework (and not one I would use if I had a choice) than a set of primitives. https://github.com/facebook/folly/tree/master/folly/io/async

comment by notacoward · 2020-04-16 · in Folly – Faceboook’s open source C++ library

…could be single small packages that would be as fast. As an example, look at this folder which: https://github.com/facebook/folly/tree/master/folly/compress... In short, these are compression tools. Why not have 1 easily uninstallable…

comment by antoineMoPa · 2020-04-16 · in Folly – Faceboook’s open source C++ library

…of data structures, algorithms, and performance utilities. The overview is much more informative: https://github.com/facebook/folly/blob/master/folly/docs/Ove...

comment by kroltan · 2020-04-16 · in Folly – Faceboook’s open source C++ library

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Folly – Faceboook’s open source C++ library

story by crakenzak · 2020-04-15 · 87 comments

…a CMOV, making the code size issue almost moot. I implemented that in fbstring back in the day: https://github.com/facebook/folly/commit/be4c6d6b3e21914df8a... This is the entirety of size(): 0f b6 57 17 movzbl 0x17(%rdi),%edx b8 17 00 00…

comment by ot · 2020-01-31 · in Libc++'s Implementation of std::string

…load [1]. A shame Folly isn't available on Compiler Explorer, would be interesting to compare. [0]: https://github.com/facebook/folly/blob/master/folly/FBString... [1]: https://godbolt.org/z/U-LvGm

comment by OskarS · 2020-01-31 · in Libc++'s Implementation of std::string

…of various cleverness detailed in that talk), but it's no longer our `std::string`. For reference: https://github.com/facebook/folly/blob/master/folly/FBString...

comment by lbrandy · 2020-01-31 · in Libc++'s Implementation of std::string

…in the experimental directory), but I guess there were some libraries trying to accomplish this. https://github.com/facebook/folly/tree/master/folly/experime...

comment by civicsquid · 2020-01-19 · in C++ coroutines: Initial implementation pushed to master

…transactions with a lock cmpxchg16b instruction, or with a more complicated algorithm like this: https://github.com/facebook/folly/blob/3de8f357eecaff89e3847...

comment by ot · 2019-11-14 · in Intel disables Hardware Lock Elision on all current CPUs

There's folly's small_vector. https://github.com/facebook/folly/blob/master/folly/docs/sma... High quality, and widely used inside Facebook. It's a shame folly isn't more widely used outside.

comment by martincmartin · 2019-10-01 · in Data Structures Part 3: Arrays of Arrays

…in https://webkit.org/blog/6161/locking-in-webkit/ ) which inspired an implementation in folly ( https://github.com/facebook/folly/blob/master/folly/synchron... ). Surprisingly, implementing futexes in userland can have performance…

comment by ot · 2019-08-01 · in Implement mechanism to wait on any of several futexes

…go at least back to Symbolics if not further. One that I thought was especially nifty was [0]. [0] https://github.com/facebook/folly/blob/master/folly/PackedSy...

comment by benreesman · 2019-07-01 · in Go Slices Are Fat Pointers

…(the base class of F14FastMap F14ValueMap and all the others) is extending std::unordered_map ? https://github.com/facebook/folly/blob/master/folly/containe... they seem to be calling the table_ member for every method in the book. Still…

comment by MichaelMoser123 · 2019-04-27 · in Open-sourcing F14 for memory-efficient hash tables

…also just insert lots of keys that all have the same hash code. See the steady_state_stats test at https://github.com/facebook/folly/blob/master/folly/containe...

comment by ngbronson · 2019-04-26 · in Open-sourcing F14 for memory-efficient hash tables

Hasn't this been open-sourced since at least last March? https://github.com/facebook/folly/commit/93d49bcf9a44d6b2d9c...

comment by alexhutcheson · 2019-04-26 · in Open-sourcing F14 for memory-efficient hash tables

…F14 maps use this strategy, and handle erase + insert workloads fine with no rehashing needed. https://github.com/facebook/folly/blob/master/folly/containe...

comment by ngbronson · 2019-03-21 · in Why Hashbrown Does a Double Lookup

…switched over to zstd organically, without our involvement, since it was such a clear win. [0] https://github.com/facebook/folly/blob/master/folly/compress...

comment by terrelln · 2018-12-19 · in Improving compression at scale with Zstandard

One thing worth trying out as well are the folly::F14 hashmaps ( https://github.com/facebook/folly/blob/master/folly/containe... ), which has a roughly similar design. You can find some discussions on the performance tradeoffs by the…

comment by ajtulloch · 2018-12-07 · in The Swiss Army Knife of Hashmaps

See also F14 ( https://github.com/facebook/folly/blob/master/folly/containe... ), it uses a similar design to SwissTable but was opensourced a few months earlier. Interestingly it is faster than SwissTable on Google's benchmarks:…

comment by ot · 2018-10-24 · in Swiss Tables and absl::Hash

…known folklore technique for quite a while. For example it was used in Folly as early as Jan 2016: https://github.com/facebook/folly/commit/b28186247104f8b90cf...

comment by ot · 2018-10-14 · in A Fast x86 Implementation of Select (2017) [pdf]

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F14 Hash Table

story by ingve · 2018-09-28 · 0 comments

As to mem allocation in vector: https://github.com/facebook/folly/blob/master/folly/docs/FBV...

comment by michal_f · 2018-09-21 · in C++ Core Coroutines Proposal [pdf]

Facebook folly: https://github.com/facebook/folly/blob/master/folly/synchron... Proposals for c++ standardization: http://www.open-std.org/jtc1/sc22/wg21/docs/papers/2016/p027...

comment by DSingularity · 2018-08-13 · in User-space RCU

An overview list on what it offers: https://github.com/facebook/folly/blob/master/folly/docs/Ove...

comment by federicoponzi · 2018-06-01 · in Folly: An open-source C++ library developed and used at Facebook

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Folly: An open-source C++ library developed and used at Facebook

story by federicoponzi · 2018-06-01 · 1 comment

Side note: FB also developed a string library to replace std::string ( https://github.com/facebook/folly/blob/master/folly/FBString... ). Here's a video from explaining the motivation behind the project (…

comment by 3uclid · 2018-04-12 · in Show HN: SuperString – A fast and memory-optimized string library for C++

…extensively internally). [0]: https://code.facebook.com/posts/745068642270222/fighting-spa... [1]: https://github.com/facebook/folly/tree/master/folly

comment by madhadron · 2017-12-23 · in Opinions on functional programming and OCaml

…Can any Googlers speak to how these projects are synchronized with the internal monorepo? [0]: https://github.com/facebook/folly [1]: https://bazel.build

comment by jzelinskie · 2017-09-28 · in Introducing Abseil, a new common libraries project

…folly, has been Apache 2.0 since at least 2012 and never had the BSD+patent license put upon it. https://github.com/facebook/folly/blob/master/LICENSE

comment by unwiredben · 2017-09-22 · in Relicensing React, Jest, Flow, and Immutable.js

There are already coroutine libraries for C++. I've used folly's Fibers with great success. https://github.com/facebook/folly/tree/master/folly/fibers

comment by martincmartin · 2017-09-07 · in C++17 is formally approved

…LLVM range-v3 https://github.com/ericniebler/range-v3 Facebook folly https://github.com/facebook/folly easylambda https://github.com/haptork/easylambda thrust https://github.com/thrust/thrust xtensor https://xtensor.readthedocs

comment by cottonseed · 2017-07-09 · in Ask HN: Name good examples of Modern C++ usage

https://github.com/facebook/folly

comment by nick0garvey · 2017-07-08 · in Ask HN: Name good examples of Modern C++ usage

Also check out https://github.com/facebook/folly which "complements" Boost and std

comment by personjerry · 2017-06-26 · in Does the Boost library meet its original goal?

…Boost I might be extremely biased about this, but I can't not recommend to follow Folly as well ( https://github.com/facebook/folly ). There is some very good C++ there (and some bad C++ too), and it is generally more readable than Boost.…

comment by ot · 2017-06-23 · in Ways to Get Better at C++

▲ 1

An Implementation of std::atomic_shared_ptr TS in Facebook's Folly

story by noahdesu · 2017-06-16 · 0 comments

…if there's cache pressure from other code. See this implementation of JSON escaping for example: https://github.com/facebook/folly/commit/2f0cabfb48b8a8df84f... De-escaping is even simpler because you only have to detect two characters, \…

comment by ot · 2017-05-26 · in Writing a Fast JSON Parser

There's also https://github.com/facebook/folly/blob/master/folly/docs/Ato... that I know of trying to solve this problem.

comment by th0br0 · 2017-05-21 · in An Atomic Hash Table