Data Random Read Write Performance

How many times per second a device can read or write to small chunks of data. Measured in IOPS (Input Outputs per Second) or MBps.

Hardware Level

• HDD usually meet 105 IOPS
• NVMe SSD meet 100,000 IOPS

OS Level

Operations with physical hardware are often the slowest part of a program. We measure IOPS during:

• Finding a file (ls)
• Opening a file
• Reading a file
• Writing to a file
• Move the file pointer (seek())
• Close the file