Section: 26.8.2 [alg.sort] Status: NAD Editorial Submitter: Paul McKenney Opened: 2008-02-27 Last modified: 2016-01-28
Priority: Not Prioritized
View all issues with NAD Editorial status.
Discussion:
Multi-threading is a good thing, but unsolicited multi-threading can
potentially be harmful. For example, sort() performance might be
greatly increased via a multithreaded implementation. However, such
a multithreaded implementation could result in concurrent invocations
of the user-supplied comparator. This would in turn result in problems
given a caching comparator that might be written for complex sort keys.
Please note that this is not a theoretical issue, as multithreaded
implementations of sort() already exist.
Having a multithreaded sort() available is good, but it should not
be the default for programs that are not explicitly multithreaded.
Users should not be forced to deal with concurrency unless they have
asked for it.
[ This may be covered by N2410 Thread-Safety in the Standard Library (Rev 1). ]
Proposed resolution:
Rationale:
This is already covered by 17.6.5.6/20 in N2723.