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Diskinfo is a small program to access the basic properties of a disk device: sectorsize, mediasize etc. It also contains a small and naïve benchmark which reports on seek and transfer performance.
2003-04-09 10:52:10 +00:00
.\"
.\" Copyright (c) 2003 Poul-Henning Kamp
Add naive benchmark for SSDs in ZFS SLOG role. ZFS SLOGs have very specific access pattern with many cache flushes, which none of benchmarks I know can simulate. Since SSD vendors rarely specify cache flush time, this measurement can be useful to explain why some ZFS pools are slower then expected. This test writes data chunks of different size followed by cache flush, alike to what ZFS SLOG does, and measures average time. To illustrate, here is result for 6 years old SATA Intel 710 Series SSD: Synchronous random writes: 0.5 kbytes: 138.3 usec/IO = 3.5 Mbytes/s 1 kbytes: 137.7 usec/IO = 7.1 Mbytes/s 2 kbytes: 151.1 usec/IO = 12.9 Mbytes/s 4 kbytes: 158.2 usec/IO = 24.7 Mbytes/s 8 kbytes: 175.6 usec/IO = 44.5 Mbytes/s 16 kbytes: 210.1 usec/IO = 74.4 Mbytes/s 32 kbytes: 274.2 usec/IO = 114.0 Mbytes/s 64 kbytes: 416.5 usec/IO = 150.1 Mbytes/s 128 kbytes: 776.6 usec/IO = 161.0 Mbytes/s 256 kbytes: 1503.1 usec/IO = 166.3 Mbytes/s 512 kbytes: 2968.7 usec/IO = 168.4 Mbytes/s 1024 kbytes: 5866.8 usec/IO = 170.5 Mbytes/s 2048 kbytes: 11696.6 usec/IO = 171.0 Mbytes/s 4096 kbytes: 23329.6 usec/IO = 171.5 Mbytes/s 8192 kbytes: 46779.5 usec/IO = 171.0 Mbytes/s , and much newer and supposedly much faster NVMe Samsung 950 PRO SSD: Synchronous random writes: 0.5 kbytes: 2092.9 usec/IO = 0.2 Mbytes/s 1 kbytes: 2013.1 usec/IO = 0.5 Mbytes/s 2 kbytes: 2014.8 usec/IO = 1.0 Mbytes/s 4 kbytes: 2090.7 usec/IO = 1.9 Mbytes/s 8 kbytes: 2044.5 usec/IO = 3.8 Mbytes/s 16 kbytes: 2084.8 usec/IO = 7.5 Mbytes/s 32 kbytes: 2137.1 usec/IO = 14.6 Mbytes/s 64 kbytes: 2173.4 usec/IO = 28.8 Mbytes/s 128 kbytes: 2923.9 usec/IO = 42.8 Mbytes/s 256 kbytes: 3085.3 usec/IO = 81.0 Mbytes/s 512 kbytes: 3112.2 usec/IO = 160.7 Mbytes/s 1024 kbytes: 2430.6 usec/IO = 411.4 Mbytes/s 2048 kbytes: 3788.9 usec/IO = 527.9 Mbytes/s 4096 kbytes: 6198.0 usec/IO = 645.4 Mbytes/s 8192 kbytes: 10764.9 usec/IO = 743.2 Mbytes/s While the first one obviously has maximal throughput limitations, the second one has so high cache flush latency (about 2 millisecond), that it makes one almost useless in SLOG role, despite of its good throughput numbers. Power loss protection is out of scope of this test, but I suspect it can be related. MFC after: 2 weeks Sponsored by: iXsystems, Inc.
2017-07-05 16:20:22 +00:00
.\" Copyright (c) 2017 Alexander Motin <mav@FreeBSD.org>
Diskinfo is a small program to access the basic properties of a disk device: sectorsize, mediasize etc. It also contains a small and naïve benchmark which reports on seek and transfer performance.
2003-04-09 10:52:10 +00:00
.\" All rights reserved.
.\"
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.\" modification, are permitted provided that the following conditions
.\" are met:
.\" 1. Redistributions of source code must retain the above copyright
.\" notice, this list of conditions and the following disclaimer.
.\" 2. Redistributions in binary form must reproduce the above copyright
.\" notice, this list of conditions and the following disclaimer in the
.\" documentation and/or other materials provided with the distribution.
.\" 3. The names of the authors may not be used to endorse or promote
.\" products derived from this software without specific prior written
.\" permission.
.\"
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.\" ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
.\" IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
.\" ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
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.\" DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
.\" OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
.\" HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
.\" LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
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.\" SUCH DAMAGE.
.\"
.\" $FreeBSD$
.\"
Add naive benchmark for SSDs in ZFS SLOG role. ZFS SLOGs have very specific access pattern with many cache flushes, which none of benchmarks I know can simulate. Since SSD vendors rarely specify cache flush time, this measurement can be useful to explain why some ZFS pools are slower then expected. This test writes data chunks of different size followed by cache flush, alike to what ZFS SLOG does, and measures average time. To illustrate, here is result for 6 years old SATA Intel 710 Series SSD: Synchronous random writes: 0.5 kbytes: 138.3 usec/IO = 3.5 Mbytes/s 1 kbytes: 137.7 usec/IO = 7.1 Mbytes/s 2 kbytes: 151.1 usec/IO = 12.9 Mbytes/s 4 kbytes: 158.2 usec/IO = 24.7 Mbytes/s 8 kbytes: 175.6 usec/IO = 44.5 Mbytes/s 16 kbytes: 210.1 usec/IO = 74.4 Mbytes/s 32 kbytes: 274.2 usec/IO = 114.0 Mbytes/s 64 kbytes: 416.5 usec/IO = 150.1 Mbytes/s 128 kbytes: 776.6 usec/IO = 161.0 Mbytes/s 256 kbytes: 1503.1 usec/IO = 166.3 Mbytes/s 512 kbytes: 2968.7 usec/IO = 168.4 Mbytes/s 1024 kbytes: 5866.8 usec/IO = 170.5 Mbytes/s 2048 kbytes: 11696.6 usec/IO = 171.0 Mbytes/s 4096 kbytes: 23329.6 usec/IO = 171.5 Mbytes/s 8192 kbytes: 46779.5 usec/IO = 171.0 Mbytes/s , and much newer and supposedly much faster NVMe Samsung 950 PRO SSD: Synchronous random writes: 0.5 kbytes: 2092.9 usec/IO = 0.2 Mbytes/s 1 kbytes: 2013.1 usec/IO = 0.5 Mbytes/s 2 kbytes: 2014.8 usec/IO = 1.0 Mbytes/s 4 kbytes: 2090.7 usec/IO = 1.9 Mbytes/s 8 kbytes: 2044.5 usec/IO = 3.8 Mbytes/s 16 kbytes: 2084.8 usec/IO = 7.5 Mbytes/s 32 kbytes: 2137.1 usec/IO = 14.6 Mbytes/s 64 kbytes: 2173.4 usec/IO = 28.8 Mbytes/s 128 kbytes: 2923.9 usec/IO = 42.8 Mbytes/s 256 kbytes: 3085.3 usec/IO = 81.0 Mbytes/s 512 kbytes: 3112.2 usec/IO = 160.7 Mbytes/s 1024 kbytes: 2430.6 usec/IO = 411.4 Mbytes/s 2048 kbytes: 3788.9 usec/IO = 527.9 Mbytes/s 4096 kbytes: 6198.0 usec/IO = 645.4 Mbytes/s 8192 kbytes: 10764.9 usec/IO = 743.2 Mbytes/s While the first one obviously has maximal throughput limitations, the second one has so high cache flush latency (about 2 millisecond), that it makes one almost useless in SLOG role, despite of its good throughput numbers. Power loss protection is out of scope of this test, but I suspect it can be related. MFC after: 2 weeks Sponsored by: iXsystems, Inc.
2017-07-05 16:20:22 +00:00
.Dd July 4, 2017
Diskinfo is a small program to access the basic properties of a disk device: sectorsize, mediasize etc. It also contains a small and naïve benchmark which reports on seek and transfer performance.
2003-04-09 10:52:10 +00:00
.Dt DISKINFO 8
.Os
.Sh NAME
.Nm diskinfo
.Nd get information about disk device
.Sh SYNOPSIS
.Nm
Add naive benchmark for SSDs in ZFS SLOG role. ZFS SLOGs have very specific access pattern with many cache flushes, which none of benchmarks I know can simulate. Since SSD vendors rarely specify cache flush time, this measurement can be useful to explain why some ZFS pools are slower then expected. This test writes data chunks of different size followed by cache flush, alike to what ZFS SLOG does, and measures average time. To illustrate, here is result for 6 years old SATA Intel 710 Series SSD: Synchronous random writes: 0.5 kbytes: 138.3 usec/IO = 3.5 Mbytes/s 1 kbytes: 137.7 usec/IO = 7.1 Mbytes/s 2 kbytes: 151.1 usec/IO = 12.9 Mbytes/s 4 kbytes: 158.2 usec/IO = 24.7 Mbytes/s 8 kbytes: 175.6 usec/IO = 44.5 Mbytes/s 16 kbytes: 210.1 usec/IO = 74.4 Mbytes/s 32 kbytes: 274.2 usec/IO = 114.0 Mbytes/s 64 kbytes: 416.5 usec/IO = 150.1 Mbytes/s 128 kbytes: 776.6 usec/IO = 161.0 Mbytes/s 256 kbytes: 1503.1 usec/IO = 166.3 Mbytes/s 512 kbytes: 2968.7 usec/IO = 168.4 Mbytes/s 1024 kbytes: 5866.8 usec/IO = 170.5 Mbytes/s 2048 kbytes: 11696.6 usec/IO = 171.0 Mbytes/s 4096 kbytes: 23329.6 usec/IO = 171.5 Mbytes/s 8192 kbytes: 46779.5 usec/IO = 171.0 Mbytes/s , and much newer and supposedly much faster NVMe Samsung 950 PRO SSD: Synchronous random writes: 0.5 kbytes: 2092.9 usec/IO = 0.2 Mbytes/s 1 kbytes: 2013.1 usec/IO = 0.5 Mbytes/s 2 kbytes: 2014.8 usec/IO = 1.0 Mbytes/s 4 kbytes: 2090.7 usec/IO = 1.9 Mbytes/s 8 kbytes: 2044.5 usec/IO = 3.8 Mbytes/s 16 kbytes: 2084.8 usec/IO = 7.5 Mbytes/s 32 kbytes: 2137.1 usec/IO = 14.6 Mbytes/s 64 kbytes: 2173.4 usec/IO = 28.8 Mbytes/s 128 kbytes: 2923.9 usec/IO = 42.8 Mbytes/s 256 kbytes: 3085.3 usec/IO = 81.0 Mbytes/s 512 kbytes: 3112.2 usec/IO = 160.7 Mbytes/s 1024 kbytes: 2430.6 usec/IO = 411.4 Mbytes/s 2048 kbytes: 3788.9 usec/IO = 527.9 Mbytes/s 4096 kbytes: 6198.0 usec/IO = 645.4 Mbytes/s 8192 kbytes: 10764.9 usec/IO = 743.2 Mbytes/s While the first one obviously has maximal throughput limitations, the second one has so high cache flush latency (about 2 millisecond), that it makes one almost useless in SLOG role, despite of its good throughput numbers. Power loss protection is out of scope of this test, but I suspect it can be related. MFC after: 2 weeks Sponsored by: iXsystems, Inc.
2017-07-05 16:20:22 +00:00
.Op Fl citSvw
Diskinfo is a small program to access the basic properties of a disk device: sectorsize, mediasize etc. It also contains a small and naïve benchmark which reports on seek and transfer performance.
2003-04-09 10:52:10 +00:00
.Ar disk ...
Add -s (serial) and -p (physpath) to diskinfo Return the bare requested information, intended for scripting. The serial number of a SAS/SCSI device can be returned with 'camcontrol inquiry disk -S', but there is no similar switch for SATA. This provides a way to get this information from both SAS and SATA disks the -s and -p flags are mutually exclusive, and cannot be used with any other flags. Reviewed by: rpokala, wblock MFC after: 1 month Sponsored by: ScaleEngine Inc. Differential Revision: https://reviews.freebsd.org/D7828
2017-07-01 21:34:57 +00:00
.Nm
.Op Fl p
.Ar disk ...
.Nm
.Op Fl s
.Ar disk ...
Diskinfo is a small program to access the basic properties of a disk device: sectorsize, mediasize etc. It also contains a small and naïve benchmark which reports on seek and transfer performance.
2003-04-09 10:52:10 +00:00
.Sh DESCRIPTION
The
.Nm
Assorted mdoc(7) fixes.
2003-05-31 18:07:09 +00:00
utility prints out information about a disk device,
and optionally runs a naive performance test on the device.
Diskinfo is a small program to access the basic properties of a disk device: sectorsize, mediasize etc. It also contains a small and naïve benchmark which reports on seek and transfer performance.
2003-04-09 10:52:10 +00:00
.Pp
Small tweaks to the diskinfo(8) manual page, to make it more consistent with others. MFC after: 1 month
2016-09-22 07:55:07 +00:00
The following options are available:
.Bl -tag -width ".Fl v"
.It Fl v
Print fields one per line with a descriptive comment.
.It Fl c
Perform a simple measurement of the I/O read command overhead.
.It Fl i
Perform a simple IOPS benchmark.
Add -s (serial) and -p (physpath) to diskinfo Return the bare requested information, intended for scripting. The serial number of a SAS/SCSI device can be returned with 'camcontrol inquiry disk -S', but there is no similar switch for SATA. This provides a way to get this information from both SAS and SATA disks the -s and -p flags are mutually exclusive, and cannot be used with any other flags. Reviewed by: rpokala, wblock MFC after: 1 month Sponsored by: ScaleEngine Inc. Differential Revision: https://reviews.freebsd.org/D7828
2017-07-01 21:34:57 +00:00
.It Fl p
Return the physical path of the disk.
This is a string that identifies the physical path to the disk in the
diskinfo(8): correct typo in man page Reported by: N.J. Mann <njm@njm.me.uk>
2017-07-02 16:20:49 +00:00
storage enclosure.
Add -s (serial) and -p (physpath) to diskinfo Return the bare requested information, intended for scripting. The serial number of a SAS/SCSI device can be returned with 'camcontrol inquiry disk -S', but there is no similar switch for SATA. This provides a way to get this information from both SAS and SATA disks the -s and -p flags are mutually exclusive, and cannot be used with any other flags. Reviewed by: rpokala, wblock MFC after: 1 month Sponsored by: ScaleEngine Inc. Differential Revision: https://reviews.freebsd.org/D7828
2017-07-01 21:34:57 +00:00
.It Fl s
Fix copy/paste error in diskinfo.8 from r320555 MFC after: 1 week Sponsored by: Spectra Logic Corp
2017-10-03 17:00:01 +00:00
Return the disk ident, usually the serial number.
Add naive benchmark for SSDs in ZFS SLOG role. ZFS SLOGs have very specific access pattern with many cache flushes, which none of benchmarks I know can simulate. Since SSD vendors rarely specify cache flush time, this measurement can be useful to explain why some ZFS pools are slower then expected. This test writes data chunks of different size followed by cache flush, alike to what ZFS SLOG does, and measures average time. To illustrate, here is result for 6 years old SATA Intel 710 Series SSD: Synchronous random writes: 0.5 kbytes: 138.3 usec/IO = 3.5 Mbytes/s 1 kbytes: 137.7 usec/IO = 7.1 Mbytes/s 2 kbytes: 151.1 usec/IO = 12.9 Mbytes/s 4 kbytes: 158.2 usec/IO = 24.7 Mbytes/s 8 kbytes: 175.6 usec/IO = 44.5 Mbytes/s 16 kbytes: 210.1 usec/IO = 74.4 Mbytes/s 32 kbytes: 274.2 usec/IO = 114.0 Mbytes/s 64 kbytes: 416.5 usec/IO = 150.1 Mbytes/s 128 kbytes: 776.6 usec/IO = 161.0 Mbytes/s 256 kbytes: 1503.1 usec/IO = 166.3 Mbytes/s 512 kbytes: 2968.7 usec/IO = 168.4 Mbytes/s 1024 kbytes: 5866.8 usec/IO = 170.5 Mbytes/s 2048 kbytes: 11696.6 usec/IO = 171.0 Mbytes/s 4096 kbytes: 23329.6 usec/IO = 171.5 Mbytes/s 8192 kbytes: 46779.5 usec/IO = 171.0 Mbytes/s , and much newer and supposedly much faster NVMe Samsung 950 PRO SSD: Synchronous random writes: 0.5 kbytes: 2092.9 usec/IO = 0.2 Mbytes/s 1 kbytes: 2013.1 usec/IO = 0.5 Mbytes/s 2 kbytes: 2014.8 usec/IO = 1.0 Mbytes/s 4 kbytes: 2090.7 usec/IO = 1.9 Mbytes/s 8 kbytes: 2044.5 usec/IO = 3.8 Mbytes/s 16 kbytes: 2084.8 usec/IO = 7.5 Mbytes/s 32 kbytes: 2137.1 usec/IO = 14.6 Mbytes/s 64 kbytes: 2173.4 usec/IO = 28.8 Mbytes/s 128 kbytes: 2923.9 usec/IO = 42.8 Mbytes/s 256 kbytes: 3085.3 usec/IO = 81.0 Mbytes/s 512 kbytes: 3112.2 usec/IO = 160.7 Mbytes/s 1024 kbytes: 2430.6 usec/IO = 411.4 Mbytes/s 2048 kbytes: 3788.9 usec/IO = 527.9 Mbytes/s 4096 kbytes: 6198.0 usec/IO = 645.4 Mbytes/s 8192 kbytes: 10764.9 usec/IO = 743.2 Mbytes/s While the first one obviously has maximal throughput limitations, the second one has so high cache flush latency (about 2 millisecond), that it makes one almost useless in SLOG role, despite of its good throughput numbers. Power loss protection is out of scope of this test, but I suspect it can be related. MFC after: 2 weeks Sponsored by: iXsystems, Inc.
2017-07-05 16:20:22 +00:00
.It Fl S
Perform synchronous random write test (ZFS SLOG test),
measuring time required to write data blocks of different size and
flush disk cache.
Blocks of more then 128KB are written with multiple parallel operations.
Small tweaks to the diskinfo(8) manual page, to make it more consistent with others. MFC after: 1 month
2016-09-22 07:55:07 +00:00
.It Fl t
Perform a simple and rather naive benchmark of the disks seek
and transfer performance.
Add naive benchmark for SSDs in ZFS SLOG role. ZFS SLOGs have very specific access pattern with many cache flushes, which none of benchmarks I know can simulate. Since SSD vendors rarely specify cache flush time, this measurement can be useful to explain why some ZFS pools are slower then expected. This test writes data chunks of different size followed by cache flush, alike to what ZFS SLOG does, and measures average time. To illustrate, here is result for 6 years old SATA Intel 710 Series SSD: Synchronous random writes: 0.5 kbytes: 138.3 usec/IO = 3.5 Mbytes/s 1 kbytes: 137.7 usec/IO = 7.1 Mbytes/s 2 kbytes: 151.1 usec/IO = 12.9 Mbytes/s 4 kbytes: 158.2 usec/IO = 24.7 Mbytes/s 8 kbytes: 175.6 usec/IO = 44.5 Mbytes/s 16 kbytes: 210.1 usec/IO = 74.4 Mbytes/s 32 kbytes: 274.2 usec/IO = 114.0 Mbytes/s 64 kbytes: 416.5 usec/IO = 150.1 Mbytes/s 128 kbytes: 776.6 usec/IO = 161.0 Mbytes/s 256 kbytes: 1503.1 usec/IO = 166.3 Mbytes/s 512 kbytes: 2968.7 usec/IO = 168.4 Mbytes/s 1024 kbytes: 5866.8 usec/IO = 170.5 Mbytes/s 2048 kbytes: 11696.6 usec/IO = 171.0 Mbytes/s 4096 kbytes: 23329.6 usec/IO = 171.5 Mbytes/s 8192 kbytes: 46779.5 usec/IO = 171.0 Mbytes/s , and much newer and supposedly much faster NVMe Samsung 950 PRO SSD: Synchronous random writes: 0.5 kbytes: 2092.9 usec/IO = 0.2 Mbytes/s 1 kbytes: 2013.1 usec/IO = 0.5 Mbytes/s 2 kbytes: 2014.8 usec/IO = 1.0 Mbytes/s 4 kbytes: 2090.7 usec/IO = 1.9 Mbytes/s 8 kbytes: 2044.5 usec/IO = 3.8 Mbytes/s 16 kbytes: 2084.8 usec/IO = 7.5 Mbytes/s 32 kbytes: 2137.1 usec/IO = 14.6 Mbytes/s 64 kbytes: 2173.4 usec/IO = 28.8 Mbytes/s 128 kbytes: 2923.9 usec/IO = 42.8 Mbytes/s 256 kbytes: 3085.3 usec/IO = 81.0 Mbytes/s 512 kbytes: 3112.2 usec/IO = 160.7 Mbytes/s 1024 kbytes: 2430.6 usec/IO = 411.4 Mbytes/s 2048 kbytes: 3788.9 usec/IO = 527.9 Mbytes/s 4096 kbytes: 6198.0 usec/IO = 645.4 Mbytes/s 8192 kbytes: 10764.9 usec/IO = 743.2 Mbytes/s While the first one obviously has maximal throughput limitations, the second one has so high cache flush latency (about 2 millisecond), that it makes one almost useless in SLOG role, despite of its good throughput numbers. Power loss protection is out of scope of this test, but I suspect it can be related. MFC after: 2 weeks Sponsored by: iXsystems, Inc.
2017-07-05 16:20:22 +00:00
.It Fl w
Allow disruptive write tests.
Small tweaks to the diskinfo(8) manual page, to make it more consistent with others. MFC after: 1 month
2016-09-22 07:55:07 +00:00
.El
.Pp
Assorted mdoc(7) fixes.
2003-05-31 18:07:09 +00:00
If given no arguments, the output will be a single line per specified device
with the following fields: device name, sectorsize, media size in bytes,
Make diskinfo report disk stripe size and offset. It should help users to make file systems optimally aligned and tuned for better performance.
2009-12-24 21:39:30 +00:00
media size in sectors, stripe size, stripe offset, firmware cylinders,
firmware heads, and firmware sectors.
Diskinfo is a small program to access the basic properties of a disk device: sectorsize, mediasize etc. It also contains a small and naïve benchmark which reports on seek and transfer performance.
2003-04-09 10:52:10 +00:00
The last three fields are only present if the information is available.
.Sh HISTORY
Assorted mdoc(7) fixes.
2003-05-31 18:07:09 +00:00
The
Diskinfo is a small program to access the basic properties of a disk device: sectorsize, mediasize etc. It also contains a small and naïve benchmark which reports on seek and transfer performance.
2003-04-09 10:52:10 +00:00
.Nm
command appeared in
Assorted mdoc(7) fixes.
2003-05-31 18:07:09 +00:00
.Fx 5.1 .
Sort sections.
2005-01-18 20:02:45 +00:00
.Sh AUTHORS
Small tweaks to the diskinfo(8) manual page, to make it more consistent with others. MFC after: 1 month
2016-09-22 07:55:07 +00:00
The
.Nm
utility was written by
.An Poul-Henning Kamp Aq Mt phk@FreeBSD.org .
Sort sections.
2005-01-18 20:02:45 +00:00
.Sh BUGS
There are in order of increasing severity: lies,
damn lies, statistics, and computer benchmarks.
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