Ryan Macnak
091b726ddf
TSAN's vector clocks become more expensive as the number of threads that touch a variable increases. The Mac/Windows/Fuchsia profilers will sample threads by suspending it and accessing it from another thread.
Cf. 13507d2594.
Change-Id: Ib303e09f04ecfdcd3b78906f850ddc2033e7b27e
Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/466900
Reviewed-by: Alexander Aprelev <aam@google.com>
Commit-Queue: Ryan Macnak <rmacnak@google.com>