Agenda  Compile-Time Rational Numbers  Durations  Clocks  Time Points  Dates  Time Zones 4 Agenda  Compile-Time Rational Numbers  Durations  Clocks  Time Points  Dates Dates  Time Zones5 Compile-Time Rational Numbers  Defined in  Work with rational numbers at compile time  Always normalized representation  Needed for durations in the library6 library6 Compile-Time Rational Numbers  Define a rational number: using r1 = ratio<1, 60>; // Represents 1/60  Retrieve numerator and denominator intmax_t num { r1::num }; intmax_t den { r1::den };

Gela Malek Pour gmalekpour@esri.com Visualize Time Enabled Data using ArcGIS Qt (C++) and ToolkitAbout Esri • We build mapping technology that our customers use to solve the world’s most complex challenges around the worldPurpose of this talk • Showcase a quick way to create a desktop app to visualize time enabled data • Setup the development environment using Esri templates • Use the ArcGIS toolkit to feature layer that include hurricane data as features • Each feature has a specific start time and end time in the feature table • We will use these start and end date values to draw and clear features

12 C++20’s Calendars and Time Zones in MSVC Miya Natsuhara ("MEE-yuh Not-soo-HAR-uh") Miya.Natsuhara@microsoft.com Software Engineer, Visual C++ LibrariesWelcome to CppCon 2021! Join Seconds • What are leap seconds? • How did we implement them in MSVC? • Part V: Time Zones • Overview of [time.zone] • IANA database challenges • Part VI: Conclusion7 Part I: Development Process8 • Code Review Videos! • clocks, clock_cast, leap_seconds (https://youtu.be/WX3OmVu4lAs) • time_zone and time_zone_link (https://youtu.be/MODhhr7m-5s) • system_clock::now(), file_clock, leap second awareness

My Code debugging Demo C++20 in action Thu, Oct 28 – 10:30am C++20’s Calendars and Time Zones in MSVC Miya Natsuhara – `Online _4 Tue, Oct 26 – 10:30am Documentation in The Era of Concepts faster Unreal Engine 4.27.1 IntelliSense Ready 18x faster Learn more at http://aka.ms/18xfaster Link time 28x faster 5x faster 18x faster 1 2 3 0.00 100.00 200.00 300.00 400.00 500.00 600.00 76 62.86 59.00 26.72 26.25 22.90 Gears 5 Link Times (lower is better) Series1 Series2 Series3 Link Time in Seconds Performance of Visual Studio Developer inner-loop Build Debug Edit Find in

Transitions SolverPerformance Precision ESP: Path-Sensitive Program Verification in Polynomial Time Path-Sensitive Dataflow Analysis with Iterative RefinementMSVC has both Path-sensitive • Use after WSL 2, and more – Sy Brand & Marian Luparu Thursday 28th • C++20’s Calendars and Time Zones in MSVC – Miya Natsuhara • An Editor Can Do That? Debugging Assembly Language and GPU Kernels

numberOfValues) { for (int i { startValue }; i < startValue + numberOfValues; ++i) { time_t t { system_clock::to_time_t(system_clock::now()) }; cout << std::ctime(&t); co_yield i; } } int main() Concepts  Named requirements to constrain template parameters  Predicates evaluated at compile time21 Concepts  Example of a concept definition: template concept Incrementable = requires(T atomic_shared_ptr head; // in C++11: remove "atomic_" and use special // functions every time you touch head public: class reference { shared_ptr p; }; auto find(T

in_range(T t) noexcept;11 constexpr Algorithms12 C++20 constexpr Everything • constexpr enables compile-time programming without arcane templates • Algorithms: • P0202R3 constexpr And exchange() Example: lookup tables • Everyone uses lookup tables • Arrays are maximally space-efficient, very time-efficient • Sorted arrays: binary_search, lower_bound, equal_range • Now you can use constexpr algorithms More advanced: constexpr sort your lookup tables14 static_assert is_sorted • Compile-time evaluation = no run-time codegen, even in debug builds #include #include #include

RECEIVER OPERATION STATE connect start …operation completes… … and notifies receiver … time passes… Implementation details of some algorithm; e.g., then. then(sender, fn) -> sender22 SHAPE state start33 OPERATIONS EXECUTE OUTSIDE-IN Receiver Work is scheduled on the thread pool Time passes…. A thread in the pool picks up the work and executes it34 OPERATIONS EXECUTE OUTSIDE-IN Senders65 NO DETACHED COMPUTATION ALLOWED schedul e schedul e then then then schedul e when_al l time set_valu e set_valu e detached computation set_erro r set_erro r A thread in the thread

SolidKey PTS Provider Transform Sinker Transform PTS Provider Transform Sinker ● Batch Inserts ○ Time trigger ○ Number trigger ● Magical Flag PTS Magical Flag Quiz PTS Magical Flag Create PTS Sync multiple data source to Clickhouse in minutes BONUS Time travel history state Create Update Update Delete insert_id id name flag update_time UUID0 2 Bob1 2 2019-10-01 00:00:00 UUID1 2 Bob1.5 2 2019-10-01 12:00:00 UUID2 2 Bob2 2 2019-10-02 00:00:00 UUID3 2 Bob2 3 2019-10-03 00:00:00 BONUS Time travel history state Create Update Update Delete Future ● Auto configure through web ● Auto deploy

mode • Services are organized in hash table • IPVS DNAT • conntrack/iptables SNAT • Pros • O(1) time complexity in control/data plane • Stably runs for two decades • Support rich scheduling algorithm differ • Performance of a cluster in different time slot may differ • Due to CPU oversold • Suggestion: • Run the test against the same cluster during near time • Make CPU the bottleneck • 1 CPU handles