Zero-Copy Pandas Dataframe Reads

[asfimport]

Arrow should be able to expose an IPC message as a Pandas dataframe without copying the data. This involves fixing:

• the alignment of the IPC message, so all columns of the same type are in contiguous buffers and so can be exposed as the 2D arrays Pandas' block manager expects.
• the arrow_to_pandas.cc code to make the UX work transparently.

Reporter: Nick White / @njwhite

PRs and other links:

• GitHub Pull Request #8644

_{Note: This issue was originally created as ARROW-10573. Please see the migration documentation for further details.}

[asfimport]

Todd Farmer / @toddfarmer: This issue was last updated over 90 days ago, which may be an indication it is no longer being actively worked. To better reflect the current state, the issue is being unassigned. Please feel free to re-take assignment of the issue if it is being actively worked, or if you plan to start that work soon.