From: Martin Kronbichler <kronbichler@lnm.mw.tum.de>
Date: Sun, 22 Mar 2020 11:45:21 +0000 (+0100)
Subject: Changelog
X-Git-Tag: v9.2.0-rc1~239^2
X-Git-Url: https://gitweb.dealii.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=7edfc8520f6d10226f36485b0e1625af082cfdb9;p=dealii.git

Changelog
---

diff --git a/doc/news/changes/incompatibilities/20200322MartinKronbichler b/doc/news/changes/incompatibilities/20200322MartinKronbichler
new file mode 100644
index 0000000000..ff38e36576
--- /dev/null
+++ b/doc/news/changes/incompatibilities/20200322MartinKronbichler
@@ -0,0 +1,6 @@
+Deprecated: SparsityTools::distribute_sparsity_pattern() and
+SparsityTools::gather_sparsity_pattern() taking the locally owned index sets
+of all processes as second arguments have been deprecated. Use the respective
+functions only providing the locally owned dofs of the calling process.
+<br>
+(Martin Kronbichler, 2020/03/22)
diff --git a/doc/news/changes/minor/20200322MartinKronbichler b/doc/news/changes/minor/20200322MartinKronbichler
new file mode 100644
index 0000000000..f644993e0f
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+++ b/doc/news/changes/minor/20200322MartinKronbichler
@@ -0,0 +1,9 @@
+New: Variants of SparsityTools::distribute_sparsity_pattern() and
+SparsityTools::gather_sparsity_pattern() taking only the locally owned index
+set of the calling MPI process have been added. They avoid the previously
+necessary MPI all-to-all communication to compute the owned dofs on all
+processes and instead go through Utilities::MPI::compute_index_owned with
+sparse communication. On more than around 1,000 MPI ranks, the new functions
+should be considerably faster.
+<br>
+(Martin Kronbichler, 2020/03/22)