Test de perf IO disque

Voir :

https://linuxfr.org/users/xunfr/journaux/how-to-bench-this-ssd

https://blog.hbis.fr/

http://strugglers.net/~andy/blog/2015/08/09/ssds-and-linux-native-command-queuing/

https://www.thomas-krenn.com/en/wiki/Linux_I/O_Performance_Tests_using_dd

https://medium.com/@kenichishibata/test-i-o-performance-of-linux-using-dd-a5074f1de9ce

https://linuxfr.org/users/xunfr/journaux/how-to-bench-this-ssd

http://drup.org/benchmarking-linux

https://wiki.mikejung.biz/Benchmarking

Voir :

atop

stress-ng

iozone3

stress-ng --all 0 --maximize --aggressive
iostat -hx 5 iostat -xmt 1

Linux : tester les performances I/O

hdparm -t -T /dev/sda dd bs=8192 count=$((4096 * 128)) if=/dev/zero of=test conv=fdatasync bonnie++ -d /mnt -r 8000 -u toto

#time -p dd if=/dev/zero of=/tmp/test1.img bs=1M count=500 oflag=dsync #time -p dd if=/dev/zero of=/tmp/test1.img bs=500M count=1 oflag=dsync time -p dd if=/dev/zero of=/tmp/test1.img bs=8192 count=$((4096 * 128)) oflag=dsync
sudo apt-get install sysbench # --file-test-mode=STRING test mode {seqwr, seqrewr, seqrd, rndrd, rndwr, rndrw} sysbench --test=fileio --file-test-mode=seqwr run sysbench --test=fileio --file-total-size=4G prepare sysbench --test=fileio --file-total-size=4G --file-test-mode=rndrd --max-time=5 run sysbench --test=fileio --file-total-size=4G --file-test-mode=rndwr --max-time=5 run sysbench --test=fileio --file-total-size=4G cleanup

Disk Read-Ahead

blockdev --report blockdev --getra /dev/sda blockdev --setra 256 /dev/sdc cat /sys/block/sda/queue/read_ahead_kb

fio

Source https://www.geekarea.fr/wordpress/?p=769

apt-get install fio
cat > plop.fio << EOF [global] bs=64k direct=1 rw=randrw ioengine=libaio iodepth=2 zonesize=256m zoneskip=2g write_bw_log=str [/dev/vdb] EOF fio plop.fio

Linux IO scheduler

# cat /sys/block/sda/queue/scheduler
noop deadline [cfq]

/etc/default/grub

# GRUB_CMDLINE_LINUX_DEFAULT="quiet splash" GRUB_CMDLINE_LINUX_DEFAULT="quiet splash elevator=noop"

IOWAIT

Voir :

https://access.redhat.com/solutions/56117