Disk Performance

Sequential Write

dd if=/dev/zero of=/tmp/tempfile bs=1M count=1024 conv=fdatasync
:'
1024+0 records in
1024+0 records out
1073741824 bytes (1.1 GB, 1.0 GiB) copied, 0.521978 s, 2.1 GB/s
'

Sequential Read » Clean Buffer

echo 'sync;echo 3 >/proc/sys/vm/drop_caches'|sudo bash
dd if=/tmp/tempfile of=/dev/null bs=1M count=1024
:'
1024+0 records in
1024+0 records out
1073741824 bytes (1.1 GB, 1.0 GiB) copied, 0.978744 s, 1.1 GB/s
'

Sequential Read » Using Buffer

dd if=/tmp/tempfile of=/dev/null bs=1M count=1024
:'
1024+0 records in
1024+0 records out
1073741824 bytes (1.1 GB, 1.0 GiB) copied, 0.151489 s, 7.1 GB/s
'

Benchmark Random Read & Write

iozone -t1 -i0 -i2 -r1k -s1g /tmp
-t  : Number of threads or processes to use in throughput test

-i  : Test to run
      0=write/rewrite,    1=read/re-read,      2=random-read/write, 3=Read-backwards,
      4=Re-write-record,  5=stride-read,       6=fwrite/re-fwrite,  7=fread/Re-fread,
      8=random_mix,       9=pwrite/Re-pwrite, 10=pread/Re-pread,   11=pwritev/Re-pwritev, 12=preadv/Re-preadv

-r  : record size in Kb
      k .. size in kB
      m .. size in MB
      g .. size in GB

-s  : file size in Kb
      k .. size in kB
      m .. size in MB
      g .. size in GB

/tmp: test path

Playground

echo 'sync;echo 3 >/proc/sys/vm/drop_caches && swapoff -a && swapon -a'|sudo bash free -th		echo 'apt update;apt list --upgradable;apt upgrade'|sudo bash bottom
docker network prune -f docker volume prune -f docker system prune -f docker image ls	cat <<'EXE' | bash for d in system network volume do docker ${d} prune -f;done EXE	cat <<'EXE' | ssh [email protected] for d in system network volume do docker ${d} prune -f;done EXE

References

Linux » Free up RAM, Cache, Buffer & Swap Linux » Disk Performance
SSH » Connection Hang Forever Free Up RAM Ruby on Rails TensorFlow Homebrew Linuxbrew PyEnv TMux CURL