office-gobmx/configmgr/source/config_map.hxx
Michael Meeks bfb978334c configmgr: faster / simpler compare for keys.
A surprising amount of time is/was spent comparing keys in the
std::map red/black tree traversing nodes. Since we don't need
the data truly sorted, instead sort in length buckets. Kills
90k rtl_ustring_compare_withLength calls on startup, around
0.9% of headless start.

Change-Id: Ib23aff151ad50d56bbf2ba3e28882cc81898d9ec
2014-06-30 15:36:26 +01:00

35 lines
1.1 KiB
C++

/* -*- Mode: C++; tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 4 -*- */
/*
* This file is part of the LibreOffice project.
*
* This Source Code Form is subject to the terms of the Mozilla Public
* License, v. 2.0. If a copy of the MPL was not distributed with this
* file, You can obtain one at http://mozilla.org/MPL/2.0/.
*/
#ifndef CONFIG_MAP_HXX
#define CONFIG_MAP_HXX
#include <map>
#include <rtl/ustring.hxx>
// The realisation here is that while a map is a reasonably compact
// representation, there is often no need to have it completely
// sorted, so we can use a fast in-line length comparison as the
// initial compare, rather than sorting of sub string contents.
struct LengthContentsCompare
{
inline bool operator()( const OUString &a, const OUString &b ) const
{
if (a.getLength() == b.getLength())
return a < b;
else
return a.getLength() < b.getLength();
}
};
template< class T > struct config_map : public std::map< OUString, T, LengthContentsCompare > { };
#endif // CONFIG_MAP_HXX
/* vim:set shiftwidth=4 softtabstop=4 expandtab: */