#!/bin/bash

COUNT=$1

RUNTIME=12
NR_FIO_JOBS=8
SCSI_DBG_NDELAY=10000

# set higher aio limit
echo 524288 > /proc/sys/fs/aio-max-nr

#figure out the CAN_QUEUE
CAN_QUEUE=$((($COUNT + 1) * ($COUNT / 2) / 2))

rmmod scsi_debug > /dev/null 2>&1
modprobe scsi_debug virtual_gb=128 max_luns=$COUNT ndelay=$SCSI_DBG_NDELAY max_queue=$CAN_QUEUE

# figure out scsi_debug disks
HOSTS=`ls -d /sys/bus/pseudo/drivers/scsi_debug/adapter0/host*`
HOSTNAME=`basename $HOSTS`
HOST=`echo $HOSTNAME | grep -o -E '[0-9]+'`

SDISKS=`ls -d /sys/bus/pseudo/drivers/scsi_debug/adapter*/$HOSTNAME/target*/*/block/*`
DISKS=""
for SD in $SDISKS; do
	DISKS+="/dev/"`basename $SD`
	DISKS+=" "
done

MY_CAN_QUEUE=`cat /sys/class/scsi_host/$HOSTNAME/can_queue`
echo "host: $HOSTNAME, can_queue: $MY_CAN_QUEUE, LUNs: $COUNT"

USE_MQ=`cat /sys/module/scsi_mod/parameters/use_blk_mq`
if [ $USE_MQ = "Y" ]; then
	SCHEDS=("none" "mq-deadline" "kyber")
else
	SCHEDS=("noop" "deadline" "cfq")
fi
SCHEDS_NR=3

FIO_JOBS=""
cnt=0
for SD in $DISKS; do
	cnt=$((cnt+1))
	FIO_JOBS=$FIO_JOBS" --name=job1 --filename=$SD: "
	DEV_NAME=`basename $SD`
	Q_PATH=/sys/block/$DEV_NAME/queue

	sched_idx=$(($cnt % $SCHEDS_NR))
	echo ${SCHEDS[$sched_idx]} > $Q_PATH/scheduler
	echo $cnt > $Q_PATH/../device/queue_depth

	MY_SCHED=`cat $Q_PATH/scheduler | sed -n 's/.*\[\(.*\)\].*/\1/p'`
	MY_SCSI_QD=`cat $Q_PATH/../device/queue_depth`
	#echo "Dev. $cnt-$DEV_NAME, SCHED: $MY_SCHED, SCSI QD: $MY_SCSI_QD"
done

echo "start I/O: $NR_FIO_JOBS jobs/disk"
fio --rw=randread --size=128G --direct=1 --ioengine=libaio --iodepth=2048 --numjobs=$NR_FIO_JOBS --bs=4k --group_reporting=1 --group_reporting=1 --runtime=$RUNTIME --loops=10000 $FIO_JOBS > /dev/null 2>&1 &

sleep 7
echo -e "delete all disks\n"
for SD in $DISKS; do
	DEV_NAME=`basename $SD`
	DPATH=/sys/block/$DEV_NAME/device
	[ -f $DPATH/delete ] && echo 1 > $DPATH/delete
done

wait