IOzone – filesystem benchmark tool

IOzone is a filesystem benchmark tool that generates and measures a wide variety of file operations.

Iozone has been ported to many machines and runs under a variety of operating systems.

Iozone is useful for determining a broad filesystem analysis of a vendor’s computer platform. The benchmark tests file I/O performance for the following operations: Read, write, re-read, re-write, read backwards, read strided, fread, fwrite, random read/write, pread/pwrite variants.

Features include:

  • POSIX async I/O – uses the POSIX standard async I/O interfaces to accomplish this.
  • Mmap() file I/O – map a file into a user’s address space. Once this mapping is in place then stores to this location in memory will result in the data being stored going to a file.
  • Normal file I/O.
  • Single stream measurement.
  • Multiple stream measurement.
  • Distributed fileserver measurements (Cluster).
  • POSIX pthreads.
  • Multi-process measurement.
  • Excel importable output for graph generation.
  • Latency plots.
  • 64bit compatible source.
  • Large file compatible.
  • Stonewalling in throughput tests to eliminate straggler effects.
  • Processor cache size configurable.
  • Selectable measurements with fsync, O_SYNC.
  • Builds for: AIX, BSDI, HP-UX, IRIX, FreeBSD, Linux, OpenBSD, NetBSD, OSFV3, OSFV4, OSFV5, SCO OpenServer, Solaris, MAC OS X, Windows (95/98/Me/NT/2K/XP).

Support: Documentation
Developer: Don Capps
License: No license requirement


IOZone is written in C. Learn C with our recommended free books and free tutorials.

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