#!/bin/bash

# Source an auxiliary options file if we have one, and pick up OPTIONS,
# SLAPD_OPTIONS, and SLURPD_OPTIONS.
if [ -r /etc/sysconfig/ldap ] ; then
	. /etc/sysconfig/ldap
fi


LDAPUSER="${LDAPUSER:-ldap}"
LDAPGROUP="${LDAPGROUP:-ldap}"
SLAPDCONF="${SLAPDCONF:-/etc/openldap/slapd.conf}"
QUIET=0

bdbdirs=(`awk \
'BEGIN {OFS=":"}
/[:space:]*^database[:space:]*\w*/ {db=$2}
/^[:space:]*directory[:space:]*\w*/ {if (db=="bdb") print $2}' \
$SLAPDCONF|sed -e 's/[" ]//g'`)

if [ -x /usr/bin/slapd_db_stat ]
then
	# private db_stat is the best choice
	DBSTAT=/usr/bin/slapd_db_stat
elif [ -x /usr/bin/db_stat ]
then
	DBSTAT=/usr/bin/db_stat
else
	DBSTAT=""
	echo  "Warning: no db_stat available"
fi

while getopts q option
do
	case "$option" in
		q) QUIET=1;;
	esac
done

function tune () {
	REPORT="$1"
	[ -n "$DBSTAT" ] || return 4
	local MEMREQ
	for dbdir in ${bdbdirs[*]}
	do
		[ "$QUIET" -eq 1 ] || echo "Checking cache size for ${dbdir}"
		MEMREQ=0
		for dbfile in ${dbdir}/*.bdb #id2entry.bdb dn2id.bdb
		do
			MEMREQ=$[MEMREQ+`$DBSTAT -h ${dbdir} -d ${dbfile}|awk '/Number of tree internal pages/ {pages=$1}; /Underlying database page size/ {page_size=$1}; END {print (pages+1)*page_size}'`]
		done
		[ -e ${dbdir}/DB_CONFIG ] && MEMUSED=`awk '/^set_cachesize/ {print (($2*1024^3)+$3)}' ${dbdir}/DB_CONFIG`
		MEMUSED="${MEMUSED:-262144}"
		if [ $MEMUSED -lt $MEMREQ ]
		then
			MEMREQGB="$[MEMREQ/1024/1024/1024]"
			MEMREQKB="$[MEMREQ%(1024*1024*1024)]"
			[ "$QUIET" -eq 1 ] || echo "\tCache memory ($MEMUSED bytes) less than minimum cache memory required ($MEMREQ bytes)"
			[ "$QUIET" -eq 1 ] || echo "You should add \"set_cachesize $MEMREQGB $MEMREQKB 0\" to ${dbdir}/DB_CONFIG"
			[ "$QUIET" -eq 1 ] || echo "and stop and start the service"
			[ "$QUIET" -eq 0 ] || echo "$dbdir set_cachesize $MEMREQGB $MEMREQKB 0"
		else
			if [ "$REPORT" == "full" ]
			then
				if [ "$QUIET" -eq 0 ]
					then echo -e "\tCache ($MEMUSED bytes) > minimum required cache ($MEMREQ bytes)"
					else echo "$dbdir ok"
				fi
			fi
		fi
		if [ "$REPORT" == "full" -a "$QUIET" -eq 0 ]
		then
			#show percentages too
			#gprintf "Cache memory set to: %s kB, minimum required cache memory: %s kB\n" "$MEMUSED" "$MEMREQ"
			PERC=`$DBSTAT -h ${dbdir} -m|awk '/Requested pages found in the cache/ {incache=$1 + incache}; /Requested pages not found in the cache/ {notincache=$1 + notincache}; END {print (incache * 100)/(notincache + incache)}'`
			echo -e "\tAverage pages found in cache for this database: $PERC %"
			if [ "${PERC%%\.*}" -lt 95 ]
			then
				echo -e"\tThis database is under-performing, you may need a bigger cache"
				echo "Please run '$DBSTAT -m -h ${dbdir}' for more statistics"
			fi
		fi
	done
}


tune full