P0261 C++ Distributed Counters

[brycelelbach]

P0261R3 C++ Distributed Counters (Lawrence Crowl)

[brycelelbach]

Kona 2019-02 LEWGI Minutes

P0261R3 Distributed Counters

Champion: Lawrence Crowl

Minute Taker: Guy Somberg

Start Overview: 9:12

Why do we need *_array?

Make it work for more types. For the integral types that std::atomic is specialized for, use std::atomic. Otherwise, use a std::mutex.

Start Discussion: 9:15

Start Polling: 9:40

POLL: Make the following changes:

• Explore making general_counter::load const.
• Make general_counter::general_counter(Integral) explicit.
• Add is_lockfree and is_always_lockfree to all the counter types.
• Make general_counter_array::general_counter_array(size_type) constexpr and explicit.
• Make general_counter_array::size and counter_broker_array::size const.

NO OBJECTION TO UNANIMOUS CONSENT

POLL: Rename general_counter* to (vote for as many as you like):

Option	Votes
general_counter	1
distributed_counter	6
counter	0
integral_counter	1
atomic_counter	6
shared_counter	3
synchronizing_counter	0

Attendance: 11

POLL: Explore supporting a wider range of types, not just Integrals that have std::atomic specializations.

Strongly For	Weakly For	Neutral	Weakly Against	Strongly Against
2	2	1	1	1

Attendance: 11

That has no consensus.

SA: Our time is limited.

POLL: We want general_counter_array and counter_broker_array for the initial version of this feature.

Strongly For	Weakly For	Neutral	Weakly Against	Strongly Against
0	3	3	1	0

Attendance: 11

End: 9:50

[wg21bot]

P0261R4 C++ Distributed Counters (Lawrence Crowl)

[cor3ntin]

@brycelelbach has SG1 seen this?

[brycelelbach]

@cor3ntin Yes, they've seen it multiple times, and forwarded it to us.