mariadb/scripts/mysql_config.sh
Davi Arnaut a10ae35328 Bug#34043: Server loops excessively in _checkchunk() when safemalloc is enabled
Essentially, the problem is that safemalloc is excruciatingly
slow as it checks all allocated blocks for overrun at each
memory management primitive, yielding a almost exponential
slowdown for the memory management functions (malloc, realloc,
free). The overrun check basically consists of verifying some
bytes of a block for certain magic keys, which catches some
simple forms of overrun. Another minor problem is violation
of aliasing rules and that its own internal list of blocks
is prone to corruption.

Another issue with safemalloc is rather the maintenance cost
as the tool has a significant impact on the server code.
Given the magnitude of memory debuggers available nowadays,
especially those that are provided with the platform malloc
implementation, maintenance of a in-house and largely obsolete
memory debugger becomes a burden that is not worth the effort
due to its slowness and lack of support for detecting more
common forms of heap corruption.

Since there are third-party tools that can provide the same
functionality at a lower or comparable performance cost, the
solution is to simply remove safemalloc. Third-party tools
can provide the same functionality at a lower or comparable
performance cost. 

The removal of safemalloc also allows a simplification of the
malloc wrappers, removing quite a bit of kludge: redefinition
of my_malloc, my_free and the removal of the unused second
argument of my_free. Since free() always check whether the
supplied pointer is null, redudant checks are also removed.

Also, this patch adds unit testing for my_malloc and moves
my_realloc implementation into the same file as the other
memory allocation primitives.
2010-07-08 18:20:08 -03:00

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#!/bin/sh
# Copyright (C) 2000-2006 MySQL AB
#
# This program is free software; you can redistribute it and/or modify
# it under the terms of the GNU General Public License as published by
# the Free Software Foundation; version 2 of the License.
#
# This program is distributed in the hope that it will be useful,
# but WITHOUT ANY WARRANTY; without even the implied warranty of
# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
# GNU General Public License for more details.
#
# You should have received a copy of the GNU General Public License
# along with this program; if not, write to the Free Software
# Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
# This script reports various configuration settings that may be needed
# when using the MySQL client library.
which ()
{
IFS="${IFS= }"; save_ifs="$IFS"; IFS=':'
for file
do
for dir in $PATH
do
if test -f $dir/$file
then
echo "$dir/$file"
continue 2
fi
done
echo "which: no $file in ($PATH)"
exit 1
done
IFS="$save_ifs"
}
#
# If we can find the given directory relatively to where mysql_config is
# we should use this instead of the incompiled one.
# This is to ensure that this script also works with the binary MySQL
# version
fix_path ()
{
var=$1
shift
for filename
do
path=$basedir/$filename
if [ -d "$path" ] ;
then
eval "$var"=$path
return
fi
done
}
get_full_path ()
{
file=$1
# if the file is a symlink, try to resolve it
if [ -h $file ];
then
file=`ls -l $file | awk '{ print $NF }'`
fi
case $file in
/*) echo "$file";;
*/*) tmp=`pwd`/$file; echo $tmp | sed -e 's;/\./;/;' ;;
*) which $file ;;
esac
}
me=`get_full_path $0`
basedir=`echo $me | sed -e 's;/bin/mysql_config;;'`
ldata='@localstatedir@'
execdir='@libexecdir@'
bindir='@bindir@'
# If installed, search for the compiled in directory first (might be "lib64")
pkglibdir='@pkglibdir@'
pkglibdir_rel=`echo $pkglibdir | sed -e "s;^$basedir/;;"`
fix_path pkglibdir $pkglibdir_rel lib/mysql lib
plugindir='@pkgplugindir@'
pkgincludedir='@pkgincludedir@'
fix_path pkgincludedir include/mysql include
version='@VERSION@'
socket='@MYSQL_UNIX_ADDR@'
ldflags='@LDFLAGS@'
if [ @MYSQL_TCP_PORT_DEFAULT@ -eq 0 ]; then
port=0
else
port=@MYSQL_TCP_PORT@
fi
# Create options
# We intentionally add a space to the beginning and end of lib strings, simplifies replace later
libs=" $ldflags -L$pkglibdir -lmysqlclient @ZLIB_DEPS@ @NON_THREADED_LIBS@"
libs="$libs @openssl_libs@ @STATIC_NSS_FLAGS@ "
libs_r=" $ldflags -L$pkglibdir -lmysqlclient_r @ZLIB_DEPS@ @LIBS@ @openssl_libs@ "
embedded_libs=" $ldflags -L$pkglibdir -lmysqld @LIBDL@ @ZLIB_DEPS@ @LIBS@ @WRAPLIBS@ @openssl_libs@ "
if [ -r "$pkglibdir/libmygcc.a" ]; then
# When linking against the static library with a different version of GCC
# from what was used to compile the library, some symbols may not be defined
# automatically. We package the libmygcc.a from the build host, to provide
# definitions for those. Bugs 4921, 19561, 19817, 21158, etc.
libs="$libs -lmygcc "
libs_r="$libs_r -lmygcc "
embedded_libs="$embedded_libs -lmygcc "
fi
cflags="-I$pkgincludedir @CFLAGS@ " #note: end space!
include="-I$pkgincludedir"
# Remove some options that a client doesn't have to care about
# FIXME until we have a --cxxflags, we need to remove -Xa
# and -xstrconst to make --cflags usable for Sun Forte C++
# FIXME until we have a --cxxflags, we need to remove -AC99
# to make --cflags usable for HP C++ (aCC)
for remove in DDBUG_OFF DSAFE_MUTEX DUNIV_MUST_NOT_INLINE DFORCE_INIT_OF_VARS \
DEXTRA_DEBUG DHAVE_purify O 'O[0-9]' 'xO[0-9]' 'W[-A-Za-z]*' \
'mtune=[-A-Za-z0-9]*' 'mcpu=[-A-Za-z0-9]*' 'march=[-A-Za-z0-9]*' \
Xa xstrconst "xc99=none" AC99 \
unroll2 ip mp restrict
do
# The first option we might strip will always have a space before it because
# we set -I$pkgincludedir as the first option
cflags=`echo "$cflags"|sed -e "s/ -$remove */ /g"`
done
cflags=`echo "$cflags"|sed -e 's/ *\$//'`
# Same for --libs(_r)
for remove in lmtmalloc static-libcxa i-static static-intel
do
# We know the strings starts with a space
libs=`echo "$libs"|sed -e "s/ -$remove */ /g"`
libs_r=`echo "$libs_r"|sed -e "s/ -$remove */ /g"`
embedded_libs=`echo "$embedded_libs"|sed -e "s/ -$remove */ /g"`
done
# Strip trailing and ending space if any, and '+' (FIXME why?)
libs=`echo "$libs" | sed -e 's; \+; ;g' | sed -e 's;^ *;;' | sed -e 's; *\$;;'`
libs_r=`echo "$libs_r" | sed -e 's; \+; ;g' | sed -e 's;^ *;;' | sed -e 's; *\$;;'`
embedded_libs=`echo "$embedded_libs" | sed -e 's; \+; ;g' | sed -e 's;^ *;;' | sed -e 's; *\$;;'`
usage () {
cat <<EOF
Usage: $0 [OPTIONS]
Options:
--cflags [$cflags]
--include [$include]
--libs [$libs]
--libs_r [$libs_r]
--plugindir [$plugindir]
--socket [$socket]
--port [$port]
--version [$version]
--libmysqld-libs [$embedded_libs]
--variable=VAR VAR is one of:
pkgincludedir [$pkgincludedir]
pkglibdir [$pkglibdir]
plugindir [$plugindir]
EOF
exit 1
}
if test $# -le 0; then usage; fi
while test $# -gt 0; do
case $1 in
--cflags) echo "$cflags" ;;
--include) echo "$include" ;;
--libs) echo "$libs" ;;
--libs_r) echo "$libs_r" ;;
--plugindir) echo "$plugindir" ;;
--socket) echo "$socket" ;;
--port) echo "$port" ;;
--version) echo "$version" ;;
--embedded-libs | --embedded | --libmysqld-libs) echo "$embedded_libs" ;;
--variable=*)
var=`echo "$1" | sed 's,^[^=]*=,,'`
case "$var" in
pkgincludedir) echo "$pkgincludedir" ;;
pkglibdir) echo "$pkglibdir" ;;
plugindir) echo "$plugindir" ;;
*) usage ;;
esac
;;
*) usage ;;
esac
shift
done
#echo "ldata: '"$ldata"'"
#echo "execdir: '"$execdir"'"
#echo "bindir: '"$bindir"'"
#echo "pkglibdir: '"$pkglibdir"'"
#echo "pkgincludedir: '"$pkgincludedir"'"
#echo "version: '"$version"'"
#echo "socket: '"$socket"'"
#echo "port: '"$port"'"
#echo "ldflags: '"$ldflags"'"
#echo "client_libs: '"$client_libs"'"
exit 0