Uwe L. Korn created ARROW-464:
---------------------------------
Summary: C++: More intelligent array growing
Key: ARROW-464
URL: https://issues.apache.org/jira/browse/ARROW-464
Project: Apache Arrow
Issue Type: Improvement
Components: C++
Reporter: Uwe L. Korn
Assignee: Uwe L. Korn
Two things to consider:
* Instead of always growing the memory to twice the size in the Builders, we
should consider 1.5 as a growth factor as this still leads to less memory
wastage. As the allocation costly is mostly linear in the number of newly
requested pages, this shouldn't be a noticeable impact. Due to memory below the
size of a single page (i.e. 4KiB) not being able to be expanded in place, we
should keep the factor of there.
* In the case of jemalloc, we can ask the allocator with the function
{{nallocx}} for the size it would actually allocate for the requested size and
then allocate this as the new capacity for the Builder/Buffer/... and not
trigger an reallocation as long as the output of {{nallocx}} doesn't change.
--
This message was sent by Atlassian JIRA
(v6.3.4#6332)
