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'''IOPS''' ([[Input/Output]] Operations Per Second, pronounced ''eye-ops'') is a common performance measurement used to [[benchmark (computing)|benchmark]] [[data storage device|computer storage]] devices like [[hard disk drive]]s (HDD), [[solid state drives]] (SSD), and [[storage area network]]s (SAN). As with any benchmark, IOPS numbers published by storage device manufacturers do not guarantee real-world application performance.<ref name=Scott_Lowe>{{cite web |url=http://www.techrepublic.com/blog/datacenter/calculate-iops-in-a-storage-array/2182 |title=Calculate IOPS in a storage array |last=Lowe |first=Scott |publisher=techrepublic.com |date=2010-02-12 |accessdate=2011-07-03}}</ref><ref name="Symantec">{{cite web |url=http://www.symantec.com/connect/articles/getting-hang-iops-v13 |title=Getting The Hang Of IOPS v1.3 |date=2012-08-03 |accessdate=2013-08-15}}</ref>
 
IOPS can be measured with applications, such as [[Iometer]] (originally developed by [[Intel]]), as well as [[IOzone]] and [[FIO (software)|FIO]]<ref>{{cite web |url=http://freshmeat.net/projects/fio/|title=Flexible IO Tester |last=Axboe |first=Jens |accessdate=2010-06-04}}(source available at http://git.kernel.dk/)</ref> and is primarily used with [[server (computing)|servers]] to find the best storage configuration.
 
The specific number of IOPS possible in any system configuration will vary greatly, depending upon the variables the tester enters into the program, including the balance of read and write operations, the mix of [[Sequential access|sequential]] and [[Random access|random]] access patterns, the number of worker [[Thread (computer science)|threads]] and queue depth, as well as the data block sizes.<ref name=Scott_Lowe/> There are other factors which can also affect the IOPS results including the system setup, storage drivers, OS background operations, etc. Also, when testing SSDs in particular, there are preconditioning considerations that must be taken into account.<ref name=Kent_Smith>{{cite web |url=http://www.lsi.com/downloads/Public/Flash%20Storage%20Processors/LSI_PRS_FMS2009_F2A_Smith.pdf |title=Benchmarking SSDs: The Devil is in the Preconditioning Details |last= Smith |first=Kent |publisher=SandForce.com |date=2009-08-11 |accessdate=2012-08-28}}</ref>
 
==Performance characteristics==
[[Image:Random vs sequential access.svg|thumb|right|Random access compared to sequential access.]]The most common performance characteristics measured are sequential and random operations. Sequential operations access locations on the storage device in a [[Contiguity#Computer science|contiguous manner]] and are generally associated with large data transfer sizes, e.g., 128&nbsp;[[Kilobyte|KB]]. Random operations access locations on the storage device in a non-contiguous manner and are generally associated with small data transfer sizes, e.g., 4&nbsp;KB.
 
The most common performance characteristics are as follows:
 
{| class="wikitable"
|-
! Measurement
! Description
|-
| Total IOPS
| Total number of I/O operations per second (when performing a mix of read and write tests)
|-
| Random Read IOPS
| Average number of random read I/O operations per second
|-
| Random Write IOPS
| Average number of random write I/O operations per second
|-
| Sequential Read IOPS
| Average number of sequential read I/O operations per second
|-
| Sequential Write IOPS
| Average number of sequential write I/O operations per second
|}
 
For HDDs and similar electromechanical storage devices, the random IOPS numbers are primarily dependent upon the storage device's random [[seek time]], whereas for SSDs and similar solid state storage devices, the random IOPS numbers are primarily dependent upon the storage device's internal controller and memory interface speeds. On both types of storage devices the sequential IOPS numbers (especially when using a large block size) typically indicate the maximum sustained bandwidth that the storage device can handle.<ref name=Scott_Lowe/> Often sequential IOPS are reported as a simple [[MB/s#Megabyte per second|MB/s]] number as follows:
 
<blockquote><math>\text{IOPS} * \text{TransferSizeInBytes} = \text{BytesPerSec}</math>    (with the answer typically converted to [[Megabytes per second|MegabytesPerSec]])
</blockquote>
 
Some HDDs will improve in performance as the number of outstanding IO's (i.e. queue depth) increases. This is usually the result of more advanced controller logic on the drive performing command queuing and reordering commonly called either [[Tagged Command Queuing]] (TCQ) or [[Native Command Queuing]] (NCQ). Most commodity [[SATA]] drives either cannot do this, or their implementation is so poor that no performance benefit can be seen.{{Citation needed|date=August 2008}} Enterprise class SATA drives, such as the [[Western Digital Raptor]] and Seagate Barracuda NL will improve by nearly 100% with deep queues.<ref>{{cite web|url=http://www.storagereview.com/articles/200607/500_6.html |title=SATA in the Enterprise - A 500 GB Drive Roundup &#124; StorageReview.com - Storage Reviews |publisher=StorageReview.com |date=2006-07-13 |accessdate=2013-05-13}}</ref> High-end [[SCSI]] drives more commonly found in servers, generally show much greater improvement, with the [[Seagate Technology|Seagate]] Savvio exceeding 400 IOPS—more than doubling its performance.{{Citation needed|date=August 2008}}
 
While traditional HDDs have about the same IOPS for read and write operations, most [[Flash memory|NAND flash-based]] SSDs are much slower writing than reading due to the inability to rewrite directly into a previously written location forcing a procedure called [[Garbage collection (SSD)|garbage collection]].<ref name="IBM_WA">{{cite web |title=Write Amplification Analysis in Flash-Based Solid State Drives |author=Hu, X.-Y. and E. Eleftheriou, R. Haas, I. Iliadis, R. Pletka |year=2009 |publisher=[[IBM]] | id = {{citeseerx|10.1.1.154.8668}} |accessdate=2010-06-02}}</ref><ref name="OCZ_WA">{{cite web |url=http://www.oczenterprise.com/whitepapers/ssds-write-amplification-trim-and-gc.pdf |title=SSDs - Write Amplification, TRIM and GC |author= |date= |work= |publisher=OCZ Technology |accessdate=2010-05-31}}</ref><ref>{{cite web |url=http://www.intel.com/cd/channel/reseller/asmo-na/eng/products/nand/feature/index.htm |title=Intel Solid State Drives |author= |date= |work= |publisher=Intel |accessdate=2010-05-31}}</ref> This has caused hardware test sites to start to provide independently measured results when testing IOPS performance.
 
Newer flash SSD drives such as the Intel X25-E have much higher IOPS than traditional hard disk drives. In a test done by Xssist, using IOmeter, 4&nbsp;KB random transfers, 70/30 read/write ratio, queue depth 4, the IOPS delivered by the Intel X25-E 64&nbsp;GB G1 started around 10000 IOPs, and dropped sharply after 8 minutes to 4000 IOPS, and continued to decrease gradually for the next 42 minutes. IOPS vary between 3000 to 4000 from around the 50th minutes onwards for the rest of the 8+ hours test run.<ref>{{cite web |url=http://www.xssist.com/blog/Intel%20X25-E%2064GB%20G1,%204KB%2070%2030%20RW%20Random%20IOPS,%20iometer%20benchmark.htm |title=Intel X25-E 64GB G1, 4KB Random IOPS, iometer benchmark |date=2010-03-27 |accessdate=2010-04-01}}</ref> Even with the drop in random IOPS after the 50th minute, the X25-E still has much higher IOPS compared to traditional hard disk drives. Some SSDs, including the [[OCZ]] RevoDrive 3 x2 PCIe using the [[SandForce]] controller, have shown much higher sustained write performance that more closely matches the read speed.<ref>{{cite web |url=http://thessdreview.com/our-reviews/ocz-revodrive-3-x2-480-gb-pcie-ssd-review-1-5gb-read1-25gb-write200000-iops-for-699/ |title=OCZ RevoDrive 3 x2 PCIe SSD Review – 1.5GB Read/1.25GB Write/200,000 IOPS As Little As $699 |date=2011-06-28 |accessdate=2011-06-30}}</ref>
 
==Examples==
 
Some com­monly accepted aver­ages for random IO operations, calculated as 1/(seek + latency) = IOPS:
{| class="wikitable"
|-
!Device
!Type
!IOPS
!Interface
!Notes
|-
| 7,200 [[Revolutions per minute|rpm]] [[SATA]] drives
| [[Hard disk drive|HDD]]
| ~75-100 IOPS<ref name="Symantec"/>
| SATA 3 [[Gbit/s]]
|
|-
| 10,000 rpm SATA drives
| HDD
| ~125-150 IOPS<ref name="Symantec"/>
| SATA 3 Gbit/s
|
|-
| 10,000 rpm [[Serial Attached SCSI|SAS]] drives
| HDD
| ~140 IOPS<ref name="Symantec"/>
| SAS
|
|-
| 15,000 rpm [[Serial Attached SCSI|SAS]] drives
| HDD
| ~175-210 IOPS<ref name="Symantec"/>
| SAS
|
|-
<!-- | 10,000 rpm [[SATA]] drives, queue depth 24
| HDD
| ~290 IOPS
| SATA 3 Gb/s
| <code>fio -readonly -name iops -rw=randread -bs=512 -runtime=20 -iodepth 24 -filename /dev/sda -ioengine libaio -direct=1</code>
|-  -->
|}
 
Solid State Devices
{| class="wikitable"
|-
!Device
!Type
!IOPS
!Interface
!Notes
|-
| Simple [[Single-level cell|SLC]] [[Solid-state drive|SSD]]
| [[Solid-state drive|SSD]]
| ~400 IOPS {{Citation needed|date=February 2010}}
| SATA 3 Gbit/s
|
|-
| [[Intel#Solid-state drives (SSD)|Intel X25-M G2]] ([[Multi-level cell|MLC]])
| SSD
| ~8,600 IOPS<ref>{{cite web |url=http://www.tomshardware.com/reviews/Intel-x25-m-SSD,2012.html |title=Intel's X25-M Solid State Drive Reviewed                |last1=Schmid |first1=Patrick |last2=Roos |first2=Achim |date=2008-09-08 |accessdate=2011-08-02}}</ref>
| SATA 3 Gbit/s
| Intel's data sheet<ref>http://download.intel.com/design/flash/nand/mainstream/322296.pdf</ref> claims 6,600/8,600 IOPS (80&nbsp;GB/160&nbsp;GB version) and 35,000 IOPS for random 4&nbsp;KB writes and reads, respectively.
|-
| [[Intel#Solid-state drives (SSD)|Intel X25-E]] (SLC)
| SSD
| ~5,000 IOPS<ref>{{cite web|author=1. |url=http://www.tomshardware.com/reviews/intel-x25-e-ssd,2158.html |title=Intel’s X25-E SSD Walks All Over The Competition : They Did It Again: X25-E For Servers Takes Off |publisher=Tomshardware.com |date= |accessdate=2013-05-13}}</ref>
| SATA 3 Gbit/s
| Intel's data sheet<ref>http://download.intel.com/design/flash/nand/extreme/extreme-sata-ssd-datasheet.pdf</ref> claims 3,300 IOPS and 35,000 IOPS for writes and reads, respectively. 5,000 IOPS are measured for a mix. Intel X25-E G1 has around 3 times higher IOPS compared to the Intel X25-M G2.<ref>{{cite web |url=http://www.xssist.com/blog/%5BSSD%5D_Comparison_of_Intel_X25-E_G1_vs_Intel_X25-M_G2.htm |title=Intel X25-E G1 vs Intel X25-M G2 Random 4&nbsp;KB IOPS, iometer |date=May 2010 |accessdate=2010-05-19}}</ref>
|-
| [[G.Skill]] Phoenix Pro
| SSD
| ~20,000 IOPS<ref name="tweakpc">{{cite web|url=http://www.tweakpc.de/hardware/tests/ssd/gskill_phoenix_pro/s05.php |title=G.Skill Phoenix Pro 120 GB Test - SandForce SF-1200 SSD mit 50K IOPS - HD Tune Access Time IOPS (Diagramme) (5/12) |publisher=Tweakpc.de |date= |accessdate=2013-05-13}}</ref>
| SATA 3 Gbit/s
| [[SandForce]]-1200 based SSD drives with enhanced firmware, states up to 50,000 IOPS, but benchmarking shows for this particular drive ~25,000 IOPS for random read and ~15,000 IOPS for random write.<ref name="tweakpc" />
|-
| [[OCZ Technology|OCZ]] Vertex 3
| SSD
| Up to 60,000 IOPS<ref>http://www.ocztechnology.com/res/manuals/OCZ_Vertex3_Product_Sheet.pdf</ref>
| SATA 6 Gbit/s
| Random Write 4&nbsp;KB (Aligned)
|-
| [[Corsair Memory|Corsair]] Force Series GT
| SSD
| Up to 85,000 IOPS<ref>{{cite web|author=Force Series™ GT 240GB SATA 3 6Gb/s Solid-State Hard Drive |url=http://www.corsair.com/us/ssd/force-series-gt-ssd/force-series-gt-240gb-sata-3-6gbps-solid-state-hard-drive.html |title=Force Series™ GT 240GB SATA 3 6Gb/s Solid-State Hard Drive - Force Series GT - SSD |publisher=Corsair.com |date= |accessdate=2013-05-13}}</ref>
| SATA 6 Gbit/s
| 240&nbsp;GB Drive, 555 MB/s sequential read & 525 MB/s sequential write, Random Write 4&nbsp;KB Test (Aligned)
|-
| [[OCZ Technology|OCZ]] Vertex 4
| SSD
| Up to 120,000 IOPS<ref>{{cite web|url=http://www.ocztechnology.com/ocz-vertex-4-sata-iii-2-5-ssd.html#overview |title=OCZ Vertex 4 SSD 2.5" SATA 3 6Gb/s |publisher=Ocztechnology.com |date= |accessdate=2013-05-13}}</ref>
| SATA 6 Gbit/s
| 256&nbsp;GB Drive, 560 MB/s sequential read & 510 MB/s sequential write, Random Read 4&nbsp;KB Test 90K IOPS, Random Write 4&nbsp;KB Test 85K IOPS
|-
| [[Texas Memory Systems]] RamSan-20
| SSD
| 120,000+ Random Read/Write IOPS<ref>{{cite web|url=http://www.ramsan.com/products/pcie-storage/ramsan-10-20 |title=IBM System Storage - Flash： Overview |publisher=Ramsan.com |date= |accessdate=2013-05-13}}</ref>
| [[PCIe]]
| Includes RAM cache
|-
| [[Fusion-io]] ioDrive
| SSD
| 140,000 Read IOPS, 135,000 Write IOPS<ref>{{cite web|url=http://community.fusionio.com/media/p/459.aspx |title=Home - Fusion-io Community Forum |publisher=Community.fusionio.com |date= |accessdate=2013-05-13}}</ref>
| PCIe
|
|-
| [[Virident Systems]] tachIOn
| SSD
| 320,000 sustained READ IOPS using 4KB blocks and 200,000 sustained WRITE IOPS using 4KB blocks<ref>http://www.theregister.co.uk/2010/06/16/virident_tachion/</ref>
| PCIe
|
|-
| OCZ RevoDrive 3 X2
| SSD
| 200,000 Random Write 4K IOPS<ref>{{cite web|url=http://www.storagereview.com/ocz_revodrive_3_x2_480gb_review |title=OCZ RevoDrive 3 X2 480GB Review &#124; StorageReview.com - Storage Reviews |publisher=StorageReview.com |date=2011-06-28 |accessdate=2013-05-13}}</ref>
| PCIe
|
|-
| Fusion-io ioDrive Duo
| SSD
| 250,000+ IOPS<ref>{{cite web|url=http://community.fusionio.com/media/p/461.aspx |title=Home - Fusion-io Community Forum |publisher=Community.fusionio.com |date= |accessdate=2013-05-13}}</ref>
| PCIe
|
|-
| [[Violin Memory]] Violin 3200
| SSD
| 250,000+ Random Read/Write IOPS<ref>[http://www.violin-memory.com/products/3200-memory-array/ ]{{dead link|date=May 2013}}</ref>
| PCIe /FC/Infiniband/iSCSI
| Flash Memory Array
|-
| WHIPTAIL, ''ACCELA''
| SSD
| 250,000/200,000+ Write/Read IOPS<ref>{{cite web|url=http://www.whiptail.com/products/accela |title=Products |publisher=Whiptail |date= |accessdate=2013-05-13}}</ref>
| Fibre Channel, iSCSI, Infiniband/SRP, NFS, CIFS
| Flash Based Storage Array
|-
| [[DDRdrive]] X1,
| SSD
| 300,000+ (512B Random Read IOPS) and 200,000+ (512B Random Write IOPS)<ref>http://www.ddrdrive.com/ddrdrive_press.pdf</ref><ref>http://www.ddrdrive.com/ddrdrive_brief.pdf</ref><ref>http://www.ddrdrive.com/ddrdrive_bench.pdf</ref><ref>{{cite web|author=Author: Allyn Malventano |url=http://www.pcper.com/article.php?aid=704 |title=DDRdrive hits the ground running - PCI-E RAM-based SSD &#124; PC Perspective |publisher=Pcper.com |date=2009-05-04 |accessdate=2013-05-13}}</ref>
| PCIe
|
|-
| SolidFire ''SF3010/SF6010''
| SSD
| 250,000 4KB Read/Write IOPS<ref>{{cite web|url=http://www.solidfire.com/solution/solidfire-storage-system/ |title=SSD Cloud Storage System - Examples & Specifications |publisher=SolidFire |date= |accessdate=2013-05-13}}</ref>
| iSCSI
| Flash Based Storage Array (5RU)
|-
|[[Texas Memory Systems]] RamSan-720 Appliance
| SSD
| 500,000 Optimal Read, 250,000 Optimal Write 4KB IOPS<ref>8. https://www.ramsan.com/files/download/798</ref>
| FC / InfiniBand
|
|-
| OCZ Single SuperScale Z-Drive R4 PCI-Express SSD
| SSD
| Up to 500,000 IOPS<ref name="OCZ_Z-Drive">{{cite web |url=http://www.ocztechnology.com/aboutocz/press/2011/445 |title=OCZ Technology Launches Next Generation Z-Drive R4 PCI Express Solid State Storage Systems |date=2011-08-02 |publisher=OCZ |accessdate=2011-08-02}}</ref>
| PCIe
|
|-
| WHIPTAIL, ''INVICTA''
| SSD
| 650,000/550,000+ Read/Write IOPS<ref>{{cite web|url=http://www.whiptail.com/products/invicta |title=Products |publisher=Whiptail |date= |accessdate=2013-05-13}}</ref>
| Fibre Channel, iSCSI, Infiniband/SRP, NFS
| Flash Based Storage Array
|-
| [[Violin Memory]] Violin 6000
| 3RU Flash Memory Array
| 1,000,000+ Random Read/Write IOPS<ref>{{cite web|author=6000 Series Flash Memory Arrays |url=http://www.violin-memory.com/products/6000-flash-memory-array/ |title=Flash Memory Arrays, Enterprise Flash Storage Violin Memory |publisher=Violin-memory.com |date= |accessdate=2013-11-14}}</ref>
| /FC/Infiniband/10Gb(iSCSI)/ PCIe
|
|-
| [[Texas Memory Systems]] RamSan-630 Appliance
| SSD
| 1,000,000+ 4KB Random Read/Write IOPS<ref>{{cite web|url=http://www.ramsan.com/products/rackmount-flash-storage/ramsan-630 |title=IBM flash storage and solutions: Overview |publisher=Ramsan.com |date= |accessdate=2013-11-14}}</ref>
| FC / InfiniBand
|
|-
| Fusion-io ioDrive Octal (single PCI Express card)
| SSD
| 1,180,000+ Random Read/Write IOPS<ref>{{cite web|url=http://www.fusionio.com/products/iodriveoctal/ |title=ioDrive Octal |publisher=Fusion-io |date= |accessdate=2013-11-14}}</ref>
| PCIe
|
|-
| OCZ 2x SuperScale Z-Drive R4 PCI-Express SSD
| SSD
| Up to 1,200,000 IOPS<ref name="OCZ_Z-Drive"/>
| PCIe
|
|-
| [[Texas Memory Systems]] RamSan-70
| SSD
| 1,200,000 Random Read/Write IOPS<ref>{{cite web|url=http://www.ramsan.com/products/pcie-storage/ramsan-70 |title=IBM flash storage and solutions: Overview |publisher=Ramsan.com |date= |accessdate=2013-11-14}}</ref>
| PCIe
| Includes RAM cache
|-
| [[Kaminario]] K2
| Flash/DRAM/Hybrid SSD
| Up to 1,200,000 IOPS SPC-1 IOPS with the K2-D ([[DRAM]])<ref name="The Register">{{cite web|last=Mellor |first=Chris |url=http://www.theregister.co.uk/2012/07/30/kaminario_spc_1/ |title=Chris Mellor, The Register, July 30, 2012: "Million-plus IOPS: Kaminario smashes IBM in DRAM decimation" |publisher=Theregister.co.uk |date=2012-07-30 |accessdate=2013-11-14}}</ref><ref name="Storage Performance Council">http://www.storageperformance.org/results/benchmark_results_spc1/#kaminario_spc1</ref>
| [[Fibre Channel|FC]]
|
|-
| Fusion-io ioDrive2
| SSD
| Up to 9,608,000 IOPS<ref>{{cite web|url=http://www.fusionio.com./press-releases/fusion-io-achieves-more-than-nine-million-iops-from-a-single-iodrive2/ |title=Achieves More Than Nine Million IOPS From a Single ioDrive2 |publisher=Fusion-io |date= |accessdate=2013-11-14}}</ref>
| PCIe
|
|}
 
==See also==
* [[Instructions per second]]
* [[Performance per watt]]
 
==References==
{{reflist|30em}}
 
{{Solid-state Drive}}
 
{{DEFAULTSORT:Iops}}
[[Category:Computer performance]]
[[Category:Data transmission]]
[[Category:Units of frequency]]

Latest revision as of 23:00, 24 December 2014

Nice to satisfy you, I am Marvella Shryock. To collect cash is one of the things I adore most. California is exactly where I've always been residing and I love every day residing right here. Hiring is his profession.

Here is my web blog :: std home test (just click the following web page)

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