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Benedict commented on CASSANDRA-6662:
-------------------------------------
bq. It should have a significant enough effect on
CollationController.collectTimeOrderedData()
I'm not totally convinced (I'm not totally unconvinced either, mind).
1) it's likely we'll add columns that are not present many times as well, here,
so we'll end up sorting anyway; and
2) I think the best thing to do here is to optimise addAll() so that if the
source is an ABSC it uses the merge logic of sort() (which could be split out,
and the columns being merged could be parameterized), and then the addAtom()
calls - which will always be unique, and in-order, will always construct a
sorted list we can efficiently merge. No binary search.
Not to say getting rid of binarySearch is still a good thing, but I think these
optimisations would be better for this spot.
I think we should also look into optimising the selection of names from the
source. We shouldn't be constructing iterators, and shouldn't be performing
binary search over the full range for every column. But that's another ticket.
> Sort/reconcile cells in ArrayBackedSortedColumns only when an accessor is
> called
> --------------------------------------------------------------------------------
>
> Key: CASSANDRA-6662
> URL: https://issues.apache.org/jira/browse/CASSANDRA-6662
> Project: Cassandra
> Issue Type: Improvement
> Reporter: Aleksey Yeschenko
> Assignee: Aleksey Yeschenko
> Fix For: 2.1
>
>
> To avoid poor performance with huge numbers of cells added out of order
> (which should be rare, but *can* happen with certain batch scenarios) we
> should make ABSC only sort/reconcile its cells when an actual accessor is
> actually called, delaying sorting until the very end.
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