From b0b28bcb501e165f77dc1e6adff6c30e4a0b0512 Mon Sep 17 00:00:00 2001 From: Wolfgang Bangerth Date: Mon, 21 Jun 2004 20:01:24 +0000 Subject: [PATCH] Improved CompressedSparsityPattern. git-svn-id: https://svn.dealii.org/trunk@9445 0785d39b-7218-0410-832d-ea1e28bc413d --- deal.II/doc/news/c-5.0.html | 15 +++++++++++++++ 1 file changed, 15 insertions(+) diff --git a/deal.II/doc/news/c-5.0.html b/deal.II/doc/news/c-5.0.html index 5996b44f5d..d5cc31154b 100644 --- a/deal.II/doc/news/c-5.0.html +++ b/deal.II/doc/news/c-5.0.html @@ -98,6 +98,21 @@ inconvenience this causes.

lac

    +
  1. + Improved: The CompressedSparsityPattern + class used one of the C++ standard containers to store the column + indices of nonzero entries in a sparse matrix. This proved to be + inefficient since it requires the allocation of 20 bytes each time an + element was added, which for large matrices can be millions of + times. The new storage format uses a more compact data structure, and a + cache that requires memory allocation only every 8 additions, on + average. This should significantly reduce the total amount of memory + required as well as memory fragmentation. It also cuts run-time for + element addition by more than half. +
    + (WB 2004/06/21) +

    +
  2. Fixed: CompressedSparsityPattern::max_entries_per_row() -- 2.39.5