[petsc-users] matsetvaluesblocked4_

[Matthew Knepley]

On Wed, May 27, 2020 at 7:34 PM Jed Brown <jed at jedbrown.org> wrote:

> Mark Adams <mfadams at lbl.gov> writes:
>
> > Nvidias's NSight with 2D Q3 and bs=10. (attached).
>
> Thanks; this is basically the same as a CPU -- the cost is searching the
> sorted rows for the next entry.  I've long thought we should optimize
> the implementations to fast-path when the next column index in the
> sparse matrix equals the next index in the provided block.  It'd just
> take a good CPU test to demonstrate that payoff.
>

So you first check whether the next index is the one in the set passed in,
and otherwise
fall back on the search? Good idea.

   Matt

-- 
What most experimenters take for granted before they begin their
experiments is infinitely more interesting than any results to which their
experiments lead.
-- Norbert Wiener

https://www.cse.buffalo.edu/~knepley/ <http://www.cse.buffalo.edu/~knepley/>
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://lists.mcs.anl.gov/pipermail/petsc-users/attachments/20200527/2b5d7b29/attachment.html>