From a4174ec43d24ff1b5cffa39f7d9ec8e9c15b9cbe Mon Sep 17 00:00:00 2001
From: Tobias Ribizel <ribizel@kit.edu>
Date: Mon, 9 May 2022 16:59:06 +0200
Subject: [PATCH] reserve storage in matrix_data constructor

---
 include/ginkgo/core/base/matrix_data.hpp | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/include/ginkgo/core/base/matrix_data.hpp b/include/ginkgo/core/base/matrix_data.hpp
index 9948b8dd3ae..f7f88694611 100644
--- a/include/ginkgo/core/base/matrix_data.hpp
+++ b/include/ginkgo/core/base/matrix_data.hpp
@@ -169,6 +169,7 @@ struct matrix_data {
         if (is_zero(value)) {
             return;
         }
+        nonzeros.reserve(size[0] * size[1]);
         for (size_type row = 0; row < size[0]; ++row) {
             for (size_type col = 0; col < size[1]; ++col) {
                 nonzeros.emplace_back(row, col, value);
@@ -190,6 +191,7 @@ struct matrix_data {
     matrix_data(dim<2> size_, RandomDistribution&& dist, RandomEngine&& engine)
         : size{size_}
     {
+        nonzeros.reserve(size[0] * size[1]);
         for (size_type row = 0; row < size[0]; ++row) {
             for (size_type col = 0; col < size[1]; ++col) {
                 const auto value =