---
name: "ioping"
section: "1"
platform: "linux"
package: "ioping"
version: "1.3-2"
release: "Arch Linux 2026-11-01"
platforms: ["linux"]
url: "https://new.carta.tech/ioping"
---

# ioping(1)

simple disk I/O latency monitoring tool

## NAME

ioping - simple disk I/O latency monitoring tool

## SYNOPSYS

**ioping** \[**-ABCDJLNRWGYykq**\] \[**-a** *count*\] \[**-b** *count*\] \[**-c** *count*\] \[**-e** *seed*\] \[**-i** *interval*\] \[**-l** *speed*\] \[**-r** *rate*\] \[**-t** *time*\] \[**-T** *time*\] \[**-s** *size*\] \[**-S** *wsize*\] \[**-o** *offset*\] \[**-w** *deadline*\] \[**-p** *period*\] \[**-P** *period*\] \[**-I** *\[format\]*\] *directory*\|*file*\|*device*\

**ioping** **-h** \| **-v**\

## DESCRIPTION

This tool generates various I/O patterns and lets you monitor I/O speed and latency in real time.

## OPTIONS

- **-a**, **-warmup** *count*

  Ignore in statistics first *count* requests, default 1. First request usually is much slower due to power-saving features.

- **-b**, **-burst** *count*

  Make series of *count* requests without delay, default **0**. Aggressive power-saving features slow down requests even after short delay.

- **-c**, **-count** *count*

  Stop after *count* requests, default **0** (infinite).

- **-e**, **-entropy** *seed*

  Set seed for random number generator, default **0** (random).

- **-i**, **-interval** *time*

  Set *time* between requests, default **1s**.

- **-l**, **-speed-limit** *size*

  Set speed limit in *size* per second. Increases interval to request-size / speed.

- **-r**, **-rate-limit** *count*

  Set rate limit in *count* per second. Increases interval to 1 / rate.

- **-t**, **-min-time** *time*

  Minimal valid request time (**0us**). Too fast requests are ignored in statistics.

- **-T**, **-max-time** *time*

  Maximum valid request time. Too slow requests are ignored in statistics.

- **-s**, **-size** *size*

  Request size, default **4k**.

- **-S**, **-work-size** *size*

  Working set size (**1m** for directory, whole size for file or device).

- **-o**, **-work-offset** *size*

  Starting offset in the file/device (0).

- **-w**, **-work-time** *time*

  Stop after *time* passed, default **0** (infinite).

- **-p**, **-print-count** *count*

  Print raw statistics for every *count* requests (see format below).

- **-P**, **-print-interval** *time*

  Print raw statistics for every *time*.

- **-A**, **-async**

  Use asynchronous I/O ([**io\_setup**(2)](/io_setup/2.md), [**io\_submit**(2)](/io_submit/2.md) etc syscalls).

- **-B**, **-batch**

  Batch mode. Be quiet and print final statistics in raw format.

- **-C**, **-cached**

  Use cached I/O. Suppress cache invalidation via [**posix\_fadvise**(2)](/posix_fadvise/2.md)) before read and [**fdatasync**(2)](/fdatasync/2.md) after each write.

- **-D**, **-direct**

  Use direct I/O (see **O\_DIRECT** in [**open**(2)](/open/2.md)).

- **-I**, **-time** *\[format\]*

  Print current time for each request. Optional argument defines time format in [**strftime**(3)](/strftime/3.md) notation, default is "%b %d %T" (Jan 01 00:00:00).

- **-J**, **-json**

  Print output in JSON format.

- **-L**, **-linear**

  Use sequential operations rather than random. This also sets default request size to **256k** (as in **-size 256k**).

- **-N**, **-nowait**

  Set RWF\_NOWAIT on I/O, indicating to the kernel to do not wait if request cannot be executed immediately. (see **RWF\_NOWAIT** in [**preadv2**(2)](/preadv2/2.md))

- **-R**, **-rapid**

  Disk seek rate test, or bandwidth test if used together with **-linear**.

  This option suppress human-readable output for each request (as **-quiet**), sets default interval to zero (**-interval 0**), stops measurement after 3 seconds (**-work-time 3**) and increases default working set size to 64m (**-work-size 64m**). Working set (**-work-size**) should be increased accordingly if disk has huge hardware cache.

- **-W**, **-write**

  Use writes rather than reads. Safe for temporary file in directory target. Write I/O gives more reliable results for systems where non-cached reads are not supported or cached at some level.

-

  Might be **\*DANGEROUS\*** for file/device: it will shred your data. In this case should be repeated three times (**-WWW**).

- **-G**, **-read-write**

  Alternate read and write requests.

- **-Y**, **-sync**

  Use sync I/O (see **O\_SYNC** in [**open**(2)](/open/2.md)).

- **-y**, **-dsync**

  Use data sync I/O (see **O\_DSYNC** in [**open**(2)](/open/2.md)).

- **-k**, **-keep**

  Keep and reuse temporary working file "ioping.tmp" (only for directory target).

- **-q**, **-quiet**

  Suppress periodical human-readable output.

- **-h**, **-help**

  Display help message and exit.

- **-v**, **-version**

  Display version and exit.

### Argument suffixes

For options that expect time argument (**-interval**, **-print-interval** and **-work-time**), default is seconds, unless you specify one of the following suffixes (case-insensitive):

- **ns**, **nsec**

  nanoseconds (a billionth of a second, 1 / 1 000 000 000)

- **us**, **usec**

  microseconds (a millionth of a second, 1 / 1 000 000)

- **ms**, **msec**

  milliseconds (a thousandth of a second, 1 / 1 000)

- **s**, **sec**

  seconds

- **m**, **min**

  minutes

- **h**, **hour**

  hours

For options that expect "size" argument (**-size**, **-speed-limit**, **-work-size** and **-work-offset**), default is bytes, unless you specify one of the following suffixes (case-insensitive):

- **sector**

  disk sectors (a sector is always 512).

- **KiB**, **k**, **kb**

  kilobytes (1 024 bytes)

- **page**

  memory pages (a page is always 4KiB).

- **MiB**, **m**, **mb**

  megabytes (1 048 576 bytes)

- **GiB**, **g**, **gb**

  gigabytes (1 073 741 824 bytes)

- **TiB**, **t**, **tb**

  terabytes (1 099 511 627 776 bytes)

For options that expect "number" argument (**-count** and **-print-count**) you can optionally specify one of the following suffixes (case-insensitive):

- **k**

  kilo (thousands, 1 000)

- **m**

  mega (millions, 1 000 000)

- **g**

  giga (billions, 1 000 000 000)

- **t**

  tera (trillions, 1 000 000 000 000)

## EXIT STATUS

Returns **0** upon success. The following error codes are defined:

- **1**

  Invalid usage (error in arguments).

- **2**

  Error during preparation stage.

- **3**

  Error during runtime.

## RAW STATISTICS

**ioping -print-count 100 -count 200 -interval 0 -quiet .**\
 `99 10970974 9024 36961531 90437 110818 358872 30756 100 12516420`\
 `100 9573265 10446 42785821 86849 95733 154609 10548 100 10649035`\
 `(1) (2)     (3)   (4)      (5)   (6)   (7)    (8)   (9) (10)`\

`(1) count of requests in statistics`\
 `(2) running time         (nanoseconds)`\
 `(3) requests per second  (iops)`\
 `(4) transfer speed       (bytes per second)`\
 `(5) minimal request time (nanoseconds)`\
 `(6) average request time (nanoseconds)`\
 `(7) maximum request time (nanoseconds)`\
 `(8) request time standard deviation (nanoseconds)`\
 `(9) total requests       (including warmup, too slow or too fast)`\
 `(10) total running time  (nanoseconds)`

## JSON OUTPUT

`With option -J|--json ioping prints json array of objects:`\
 **\[**\
 **...**\
 {\
   // timestamps\
   "timestamp": (unix time in seconds as float),\
   "localtime": (local time ISO 8601),

  // io target\
   "target": {\
     "path": (target path),\
     "fstype": (filesystem name),\
     "device": (device name),\
     "device\_size": (device size in bytes)\
   },

  // io request\
   "io": {\
     "request": (request index),\
     "operation": (request type: "read" \| "write"),\
     "size": (request size in bytes),\
     "time": (io time in ns),\
     "ignored": (ignored in statistics: true \| false)\
   },

  // statistics\
   "stat": {\
     "count": (nr reqeusts),\
     "size": (total io size in bytes),\
     "time": (total io time in ns),\
     "iops": (avg iops),\
     "bps": (avg rate),\
     "min": (min io time in ns),\
     "avg": (avg io time in ns),\
     "max": (max io time in ns),\
     "mdev": (standard deviation in ns)\
   },

  // load statistics\
   "load": {\
     "count": (nr requests),\
     "size": (total io size in bytes),\
     "time": (total real time in ns),\
     "iops": (avg iops),\
     "bps": (avg rate)\
   },\
 },\
 **...**\
 **\]**

## EXAMPLES

- **ioping .**

  Show disk I/O latency using the default values and the current directory, until interrupted. This command prepares temporary (unlinked/hidden) working file and reads random chunks from it using non-cached read requests.

- **ioping -c 10 -s 1M /tmp**

  Measure latency on **/tmp** using 10 requests of 1 megabyte each.

- **ioping -R /dev/sda**

  Measure disk seek rate.

- **ioping -RL /dev/sda**

  Measure disk sequential speed.

- **ioping -RLB . \| awk '{print $4}'**

  Get disk sequential speed in bytes per second.

- **ioping -J . \| jq -r --stream 'fromstream(1\|truncate\_stream(inputs)) \| \[.localtime, .io.time/1000000\] \| @tsv'**

  Select localtime and io time in milliseconds from json outout.

## SEE ALSO

[**iostat**(1)](/iostat/1.md), [**dd**(1)](/dd/1.md), [**fio**(1)](/fio/1.md), [**stress**(1)](/stress/1.md), [**stress-ng**(1)](/stress-ng/1.md), [**dbench**(1)](/dbench/1.md), [**sysbench**(1)](/sysbench/1.md), **fsstress,** **xfstests,** [**hdparm**(8)](/hdparm/8.md), [**badblocks**(8)](/badblocks/8.md),

## HOMEPAGE

⟨https://github.com/koct9i/ioping/⟩.

## AUTHORS

This program was written by Konstantin Khlebnikov ⟨koct9i@gmail.com⟩.\
 Man-page was written by Kir Kolyshkin ⟨kir@openvz.org⟩.