view auto/cc/sunc @ 7281:bd6563e81cea

Limit req: improved handling of negative times. Negative times can appear since workers only update time on an event loop iteration start. If a worker was blocked for a long time during an event loop iteration, it is possible that another worker already updated the time stored in the node. As such, time since last update of the node (ms) will be negative. Previous code used ngx_abs(ms) in the calculations. That is, negative times were effectively treated as positive ones. As a result, it was not possible to maintain high request rates, where the same node can be updated multiple times from during an event loop iteration. In particular, this affected setups with many SSL handshakes, see http://mailman.nginx.org/pipermail/nginx/2018-May/056291.html. Fix is to only update the last update time stored in the node if the new time is larger than previously stored one. If a future time is stored in the node, we preserve this time as is. To prevent breaking things on platforms without monotonic time available if system time is updated backwards, a safety limit of 60 seconds is used. If the time stored in the node is more than 60 seconds in the future, we assume that the time was changed backwards and update lr->last to the current time.
author Maxim Dounin <mdounin@mdounin.ru>
date Wed, 30 May 2018 15:40:34 +0300
parents d8e8ced78e77
children
line wrap: on
line source


# Copyright (C) Igor Sysoev
# Copyright (C) Nginx, Inc.


# Sun C 5.7 Patch 117837-04 2005/05/11    Sun Studio 10
# Sun C 5.8 2005/10/13                    Sun Studio 11
# Sun C 5.9 SunOS_i386 2007/05/03         Sun Studio 12
# Sun C 5.9 SunOS_sparc 2007/05/03
# Sun C 5.10 SunOS_i386 2009/06/03        Sun Studio 12.1
# Sun C 5.11 SunOS_i386 2010/08/13        Oracle Solaris Studio 12.2
# Sun C 5.12 SunOS_i386 2011/11/16        Oracle Solaris Studio 12.3
# Sun C 5.13 SunOS_i386 2014/10/20        Oracle Solaris Studio 12.4
# Sun C 5.14 SunOS_i386 2016/05/31        Oracle Developer Studio 12.5

NGX_SUNC_VER=`$CC -V 2>&1 | grep 'Sun C' 2>&1 \
                          | sed -e 's/^.* Sun C \(.*\)/\1/'`

echo " + Sun C version: $NGX_SUNC_VER"

have=NGX_COMPILER value="\"Sun C $NGX_SUNC_VER\"" . auto/define


cat << END > $NGX_AUTOTEST.c

int main(void) {
    printf("%d", __SUNPRO_C);
    return 0;
}

END

eval "$CC -o $NGX_AUTOTEST $NGX_AUTOTEST.c >> $NGX_ERR 2>&1"

if [ -x $NGX_AUTOTEST ]; then
    ngx_sunc_ver=`$NGX_AUTOTEST`
fi

rm -rf $NGX_AUTOTEST*

# 1424 == 0x590, Sun Studio 12

if [ "$ngx_sunc_ver" -ge 1424 ]; then
    ngx_sparc32="-m32"
    ngx_sparc64="-m64"
    ngx_amd64="-m64"

else
    ngx_sparc32="-xarch=v8plus"
    ngx_sparc64="-xarch=v9"
    ngx_amd64="-xarch=amd64"
fi

case "$NGX_MACHINE" in

    i86pc)
        NGX_AUX=" src/os/unix/ngx_sunpro_x86.il"
    ;;

    sun4u | sun4v)
        NGX_AUX=" src/os/unix/ngx_sunpro_sparc64.il"
    ;;

esac

MAIN_LINK=
MODULE_LINK="-G"


# optimizations

# 20736 == 0x5100, Sun Studio 12.1

if [ "$ngx_sunc_ver" -ge 20736 ]; then
    ngx_fast="-fast"

else
    # older versions had problems with bit-fields
    ngx_fast="-fast -xalias_level=any"
fi

IPO=-xipo
CFLAGS="$CFLAGS $ngx_fast $IPO"
CORE_LINK="$CORE_LINK $ngx_fast $IPO"


case $CPU in
    pentium)
        # optimize for Pentium and Athlon
        CPU_OPT="-xchip=pentium"
    ;;

    pentiumpro)
        # optimize for Pentium Pro, Pentium II
        CPU_OPT="-xchip=pentium_pro"
    ;;

    pentium3)
        # optimize for Pentium III
        CPU_OPT="-xchip=pentium3"
        #CPU_OPT="$CPU_OPT -xarch=sse"
        CPU_OPT="$CPU_OPT -xcache=16/32/4:256/32/4"
    ;;

    pentium4)
        # optimize for Pentium 4
        CPU_OPT="-xchip=pentium4"
        #CPU_OPT="$CPU_OPT -xarch=sse2"
        CPU_OPT="$CPU_OPT -xcache=8/64/4:256/128/8"
    ;;

    opteron)
        # optimize for Opteron
        CPU_OPT="-xchip=opteron"
        #CPU_OPT="$CPU_OPT -xarch=sse2"
        CPU_OPT="$CPU_OPT -xcache=64/64/2:1024/64/16"
    ;;

    sparc32)
        # build 32-bit UltraSparc binary
        CPU_OPT="$ngx_sparc32"
        CORE_LINK="$CORE_LINK $ngx_sparc32"
        CC_AUX_FLAGS="$CC_AUX_FLAGS $ngx_sparc32"
        NGX_CPU_CACHE_LINE=64
    ;;

    sparc64)
        # build 64-bit UltraSparc binary
        CPU_OPT="$ngx_sparc64"
        CORE_LINK="$CORE_LINK $ngx_sparc64"
        CC_AUX_FLAGS="$CC_AUX_FLAGS $ngx_sparc64"
        NGX_CPU_CACHE_LINE=64
    ;;

    amd64)
        # build 64-bit amd64 binary
        CPU_OPT="$ngx_amd64"
        CORE_LINK="$CORE_LINK $ngx_amd64"
        CC_AUX_FLAGS="$CC_AUX_FLAGS $ngx_amd64"
        NGX_AUX=" src/os/unix/ngx_sunpro_amd64.il"
        NGX_CPU_CACHE_LINE=64
    ;;

esac


CFLAGS="$CFLAGS $CPU_OPT"


if [ ".$PCRE_OPT" = "." ]; then
    PCRE_OPT="$ngx_fast $IPO $CPU_OPT"
fi

if [ ".$ZLIB_OPT" = "." ]; then
    ZLIB_OPT="$ngx_fast $IPO $CPU_OPT"
fi


# stop on warning
CFLAGS="$CFLAGS -errwarn=%all"

# debug
CFLAGS="$CFLAGS -g"