Overclock.net › Forums › Components › Hard Drives & Storage › What kind of speed should I expect out of RAID5?
New Posts  All Forums:Forum Nav:

What kind of speed should I expect out of RAID5?

post #1 of 32
Thread Starter 
I am going to have 3 750GB Barracuda 7200.11 in RAID5. What kind of speed should I expect? I know it is nothing like RAID1.
 
Gsvlip Dudyrm
(15 items)
 
Oda'maksv
(9 items)
 
CPUMotherboardGraphicsRAM
3770k @ 4.5 1.312 load Zotac Z77 ITX Wifi GTX 1070 Gaming 2126/2249 w/ Hybrid cooler TridentX 16GB 2400MHz 
Hard DriveHard DriveCoolingCooling
Samsung 850 Pro 1TB Seagate 2TB H105 EVGA Hybrid GPU cooler 
OSMonitorKeyboardPower
Windows 10 Asus MG279Q - 24" 144Hz 1080p Filco Majestic II w/ Cherry Reds Seasonic X 760W 
CaseMouseMouse PadAudio
Bitfelix Prodigy Logitech G400 Razer Goliath AKG A701 
AudioAudio
JDS Labs Objective 2 JDS Labs ODAC 
CPUMotherboardGraphicsRAM
Core i5 750 3.99 (190x21) 1.376v Load ASUS P7P55d-E Pro GTX 670 FTW <- Poor overclocker :( 8GB (4x2GB) G.Skill DDR3 1600 
Hard DriveHard DriveOptical DriveOS
Samsung 830 Evo 128GB 2x 2TB  Some DVD drive OSX 10.10.4 
MonitorPowerCaseMouse
Asus 1080P Crap TX 750 HAF 922 G400s 
Mouse PadOther
Apple Keyboard Xbox One controler 
CPURAMHard DriveHard Drive
C2D 2,26GHz under volted @ .978v 8GB  Crucial M4 64GB SSD 500GB Scorpio Black 
OSMonitorKeyboardMouse
OS X 10.0 1280x800 Built-in Trackpad 
Audio
Built-in 
  hide details  
Reply
 
Gsvlip Dudyrm
(15 items)
 
Oda'maksv
(9 items)
 
CPUMotherboardGraphicsRAM
3770k @ 4.5 1.312 load Zotac Z77 ITX Wifi GTX 1070 Gaming 2126/2249 w/ Hybrid cooler TridentX 16GB 2400MHz 
Hard DriveHard DriveCoolingCooling
Samsung 850 Pro 1TB Seagate 2TB H105 EVGA Hybrid GPU cooler 
OSMonitorKeyboardPower
Windows 10 Asus MG279Q - 24" 144Hz 1080p Filco Majestic II w/ Cherry Reds Seasonic X 760W 
CaseMouseMouse PadAudio
Bitfelix Prodigy Logitech G400 Razer Goliath AKG A701 
AudioAudio
JDS Labs Objective 2 JDS Labs ODAC 
CPUMotherboardGraphicsRAM
Core i5 750 3.99 (190x21) 1.376v Load ASUS P7P55d-E Pro GTX 670 FTW <- Poor overclocker :( 8GB (4x2GB) G.Skill DDR3 1600 
Hard DriveHard DriveOptical DriveOS
Samsung 830 Evo 128GB 2x 2TB  Some DVD drive OSX 10.10.4 
MonitorPowerCaseMouse
Asus 1080P Crap TX 750 HAF 922 G400s 
Mouse PadOther
Apple Keyboard Xbox One controler 
CPURAMHard DriveHard Drive
C2D 2,26GHz under volted @ .978v 8GB  Crucial M4 64GB SSD 500GB Scorpio Black 
OSMonitorKeyboardMouse
OS X 10.0 1280x800 Built-in Trackpad 
Audio
Built-in 
  hide details  
Reply
post #2 of 32
Fortunately for us RAID is quite mathematical in its performance

RAID 0, as we know is the number of drives * speed. Therefore with 2 drives you get 2*speed of the drive.

With RAID 5 however, you are dealing with a slew of factors such as overhead computing power, RAID card performance and the stripe size you have allocated(128kb etc).

Knowing this, the typical RAID 5 array will display performance = (n-1) * speed. This is because you are keeping one drive for correctional parity information, and only the other two spindles actually record data.

You may be thinking now that you should get the speed of two drives(like in RAID 0) but we haven't factored in the RAID card's capabilities and the time it takes to process the parity information into meta-data.

Therefore, if we were to compare a RAID 5 array to a RAID 0, the following comparisons would immediately be apparent.

- Reduced random read speed(but only by a small amount)
- Drastically reduced write speeds(of course, there is a huge CPU overhead here on the RAID Card)
- Fault tolerance of 1 drive(over 0 in RAID 0).
- Of course read//write speeds will depend on the stripe size you have set up, if you wish to know about how stripe size affects the performance of your array post back.


Hope this has been helpful in some way.
Edited by Razultull - 4/16/11 at 7:13am
Bernard
(13 items)
 
  
CPUMotherboardGraphicsRAM
i7 950 @ 3.71 Ghz | 1.17v Rampage III Extreme EVGA GTX 580 Corsair Dominators GTX 6gb 1925MHz 7-7-7-20 
Hard DriveOptical DriveOSMonitor
64Gb C300 SATA 6 Gb/s, 2 x 320 Gb F4's RAID 0 ASUS 24x -_- Windows 7 Home(Who needs ultimate?!) ASUS VH226H 21.5 Inch 1080p 
PowerCaseMouseMouse Pad
Corsair HX1000 + Custom Sleeving NZXT Tempest Evo Razer Naga NONE 
  hide details  
Reply
Bernard
(13 items)
 
  
CPUMotherboardGraphicsRAM
i7 950 @ 3.71 Ghz | 1.17v Rampage III Extreme EVGA GTX 580 Corsair Dominators GTX 6gb 1925MHz 7-7-7-20 
Hard DriveOptical DriveOSMonitor
64Gb C300 SATA 6 Gb/s, 2 x 320 Gb F4's RAID 0 ASUS 24x -_- Windows 7 Home(Who needs ultimate?!) ASUS VH226H 21.5 Inch 1080p 
PowerCaseMouseMouse Pad
Corsair HX1000 + Custom Sleeving NZXT Tempest Evo Razer Naga NONE 
  hide details  
Reply
post #3 of 32
What was posted above it true, but to sumarize it in one sentance:

What controller are you using, what stripe size are you planing on and what will you be writing to the array?
post #4 of 32
Here's an example for the equation for RAID 0 Razultull. 2 drives * 7200rpm=14400. For RAID 5, n would be the number of drives so (5-1)*7200rpm=4*7200rpm=28800.
Trinity
(19 items)
 
  
CPUMotherboardGraphicsRAM
AMD A10-5800K Biostar Hi-Fi A85W APU Integrated Graphics G.Skill 8GB (2 x 4GB) 1600MHz CL9 
Hard DriveHard DriveOptical DriveCooling
Crucial M4 64GB Western Digital WD Blue 500GB Lite-On iHAS124 CD/DVD Burner Cooler Master Hyper 212 EVO (Pull Configuration) 
OSMonitorMonitorKeyboard
Windows 7 Home Premium 64-Bit NEC MultiSync LCD1970VX NEC MultiSync LCD1970VX Filco Majestouch Black w/ Cherry MX Blue (JIS l... 
PowerCaseMouseMouse Pad
Corsair CX430 NZXT Source 220 Logitech Click! Mouse SteelSeries QcK Mini Diablo III Edition 
AudioAudioOther
Sony SRS-T10PC USB Portable Speaker Realtek Onboard Audio Intel Centrino Desktop Wireless 
  hide details  
Reply
Trinity
(19 items)
 
  
CPUMotherboardGraphicsRAM
AMD A10-5800K Biostar Hi-Fi A85W APU Integrated Graphics G.Skill 8GB (2 x 4GB) 1600MHz CL9 
Hard DriveHard DriveOptical DriveCooling
Crucial M4 64GB Western Digital WD Blue 500GB Lite-On iHAS124 CD/DVD Burner Cooler Master Hyper 212 EVO (Pull Configuration) 
OSMonitorMonitorKeyboard
Windows 7 Home Premium 64-Bit NEC MultiSync LCD1970VX NEC MultiSync LCD1970VX Filco Majestouch Black w/ Cherry MX Blue (JIS l... 
PowerCaseMouseMouse Pad
Corsair CX430 NZXT Source 220 Logitech Click! Mouse SteelSeries QcK Mini Diablo III Edition 
AudioAudioOther
Sony SRS-T10PC USB Portable Speaker Realtek Onboard Audio Intel Centrino Desktop Wireless 
  hide details  
Reply
post #5 of 32
Thread Starter 
Onboard Intel RAID controller (AKA my SB). I am going to leave the stripe size default. It is mainly for backup.
 
Gsvlip Dudyrm
(15 items)
 
Oda'maksv
(9 items)
 
CPUMotherboardGraphicsRAM
3770k @ 4.5 1.312 load Zotac Z77 ITX Wifi GTX 1070 Gaming 2126/2249 w/ Hybrid cooler TridentX 16GB 2400MHz 
Hard DriveHard DriveCoolingCooling
Samsung 850 Pro 1TB Seagate 2TB H105 EVGA Hybrid GPU cooler 
OSMonitorKeyboardPower
Windows 10 Asus MG279Q - 24" 144Hz 1080p Filco Majestic II w/ Cherry Reds Seasonic X 760W 
CaseMouseMouse PadAudio
Bitfelix Prodigy Logitech G400 Razer Goliath AKG A701 
AudioAudio
JDS Labs Objective 2 JDS Labs ODAC 
CPUMotherboardGraphicsRAM
Core i5 750 3.99 (190x21) 1.376v Load ASUS P7P55d-E Pro GTX 670 FTW <- Poor overclocker :( 8GB (4x2GB) G.Skill DDR3 1600 
Hard DriveHard DriveOptical DriveOS
Samsung 830 Evo 128GB 2x 2TB  Some DVD drive OSX 10.10.4 
MonitorPowerCaseMouse
Asus 1080P Crap TX 750 HAF 922 G400s 
Mouse PadOther
Apple Keyboard Xbox One controler 
CPURAMHard DriveHard Drive
C2D 2,26GHz under volted @ .978v 8GB  Crucial M4 64GB SSD 500GB Scorpio Black 
OSMonitorKeyboardMouse
OS X 10.0 1280x800 Built-in Trackpad 
Audio
Built-in 
  hide details  
Reply
 
Gsvlip Dudyrm
(15 items)
 
Oda'maksv
(9 items)
 
CPUMotherboardGraphicsRAM
3770k @ 4.5 1.312 load Zotac Z77 ITX Wifi GTX 1070 Gaming 2126/2249 w/ Hybrid cooler TridentX 16GB 2400MHz 
Hard DriveHard DriveCoolingCooling
Samsung 850 Pro 1TB Seagate 2TB H105 EVGA Hybrid GPU cooler 
OSMonitorKeyboardPower
Windows 10 Asus MG279Q - 24" 144Hz 1080p Filco Majestic II w/ Cherry Reds Seasonic X 760W 
CaseMouseMouse PadAudio
Bitfelix Prodigy Logitech G400 Razer Goliath AKG A701 
AudioAudio
JDS Labs Objective 2 JDS Labs ODAC 
CPUMotherboardGraphicsRAM
Core i5 750 3.99 (190x21) 1.376v Load ASUS P7P55d-E Pro GTX 670 FTW <- Poor overclocker :( 8GB (4x2GB) G.Skill DDR3 1600 
Hard DriveHard DriveOptical DriveOS
Samsung 830 Evo 128GB 2x 2TB  Some DVD drive OSX 10.10.4 
MonitorPowerCaseMouse
Asus 1080P Crap TX 750 HAF 922 G400s 
Mouse PadOther
Apple Keyboard Xbox One controler 
CPURAMHard DriveHard Drive
C2D 2,26GHz under volted @ .978v 8GB  Crucial M4 64GB SSD 500GB Scorpio Black 
OSMonitorKeyboardMouse
OS X 10.0 1280x800 Built-in Trackpad 
Audio
Built-in 
  hide details  
Reply
post #6 of 32
Thread Starter 
Quote:
Originally Posted by Razultull View Post
Fortunately for us RAID is quite mathematical in its performance

RAID 0, as we know is the number of drives * speed. Therefore with 2 drives you get 2*speed of the drive.

With RAID 5 however, you are dealing with a slew of factors such as overhead computing power, RAID card performance and the stripe size you have allocated(128kb etc).

Knowing this, the typical RAID 5 array will display performance = (n-1) * speed. This is because you are keeping one drive for correctional parity information, and only the other two spindles actually record data.

You may be thinking now that you should get the speed of two drives(like in RAID 0) but we haven't factored in the RAID card's capabilities and the time it takes to process the parity information into meta-data.

Therefore, if we were to compare a RAID 5 array to a RAID 0, the following comparisons would immediately be apparent.

- Reduced random read speed(but only by a small amount)
- Drastically reduced write speeds(of course, there is a huge CPU overhead here on the RAID Card)
- Fault tolerance of 1 drive(over 0 in RAID 0).
- Of course read//write speeds will depend on the stripe size you have set up, if you wish to know about how stripe size affects the performance of your array post back.


Hope this has been helpful in some way.
RAID5 has the parity information spread across all disks, not just put onto one. the RAID your refering to is RAID3
 
Gsvlip Dudyrm
(15 items)
 
Oda'maksv
(9 items)
 
CPUMotherboardGraphicsRAM
3770k @ 4.5 1.312 load Zotac Z77 ITX Wifi GTX 1070 Gaming 2126/2249 w/ Hybrid cooler TridentX 16GB 2400MHz 
Hard DriveHard DriveCoolingCooling
Samsung 850 Pro 1TB Seagate 2TB H105 EVGA Hybrid GPU cooler 
OSMonitorKeyboardPower
Windows 10 Asus MG279Q - 24" 144Hz 1080p Filco Majestic II w/ Cherry Reds Seasonic X 760W 
CaseMouseMouse PadAudio
Bitfelix Prodigy Logitech G400 Razer Goliath AKG A701 
AudioAudio
JDS Labs Objective 2 JDS Labs ODAC 
CPUMotherboardGraphicsRAM
Core i5 750 3.99 (190x21) 1.376v Load ASUS P7P55d-E Pro GTX 670 FTW <- Poor overclocker :( 8GB (4x2GB) G.Skill DDR3 1600 
Hard DriveHard DriveOptical DriveOS
Samsung 830 Evo 128GB 2x 2TB  Some DVD drive OSX 10.10.4 
MonitorPowerCaseMouse
Asus 1080P Crap TX 750 HAF 922 G400s 
Mouse PadOther
Apple Keyboard Xbox One controler 
CPURAMHard DriveHard Drive
C2D 2,26GHz under volted @ .978v 8GB  Crucial M4 64GB SSD 500GB Scorpio Black 
OSMonitorKeyboardMouse
OS X 10.0 1280x800 Built-in Trackpad 
Audio
Built-in 
  hide details  
Reply
 
Gsvlip Dudyrm
(15 items)
 
Oda'maksv
(9 items)
 
CPUMotherboardGraphicsRAM
3770k @ 4.5 1.312 load Zotac Z77 ITX Wifi GTX 1070 Gaming 2126/2249 w/ Hybrid cooler TridentX 16GB 2400MHz 
Hard DriveHard DriveCoolingCooling
Samsung 850 Pro 1TB Seagate 2TB H105 EVGA Hybrid GPU cooler 
OSMonitorKeyboardPower
Windows 10 Asus MG279Q - 24" 144Hz 1080p Filco Majestic II w/ Cherry Reds Seasonic X 760W 
CaseMouseMouse PadAudio
Bitfelix Prodigy Logitech G400 Razer Goliath AKG A701 
AudioAudio
JDS Labs Objective 2 JDS Labs ODAC 
CPUMotherboardGraphicsRAM
Core i5 750 3.99 (190x21) 1.376v Load ASUS P7P55d-E Pro GTX 670 FTW <- Poor overclocker :( 8GB (4x2GB) G.Skill DDR3 1600 
Hard DriveHard DriveOptical DriveOS
Samsung 830 Evo 128GB 2x 2TB  Some DVD drive OSX 10.10.4 
MonitorPowerCaseMouse
Asus 1080P Crap TX 750 HAF 922 G400s 
Mouse PadOther
Apple Keyboard Xbox One controler 
CPURAMHard DriveHard Drive
C2D 2,26GHz under volted @ .978v 8GB  Crucial M4 64GB SSD 500GB Scorpio Black 
OSMonitorKeyboardMouse
OS X 10.0 1280x800 Built-in Trackpad 
Audio
Built-in 
  hide details  
Reply
post #7 of 32
Quote:
Originally Posted by HybridCore View Post
Here's an example for the equation for RAID 0 Razultull. 2 drives * 7200rpm=14400. For RAID 5, n would be the number of drives so (5-1)*7200rpm=4*7200rpm=28800.
RAID 5 is not necessarily 5 drives....you need a minimum of 3.
Bernard
(13 items)
 
  
CPUMotherboardGraphicsRAM
i7 950 @ 3.71 Ghz | 1.17v Rampage III Extreme EVGA GTX 580 Corsair Dominators GTX 6gb 1925MHz 7-7-7-20 
Hard DriveOptical DriveOSMonitor
64Gb C300 SATA 6 Gb/s, 2 x 320 Gb F4's RAID 0 ASUS 24x -_- Windows 7 Home(Who needs ultimate?!) ASUS VH226H 21.5 Inch 1080p 
PowerCaseMouseMouse Pad
Corsair HX1000 + Custom Sleeving NZXT Tempest Evo Razer Naga NONE 
  hide details  
Reply
Bernard
(13 items)
 
  
CPUMotherboardGraphicsRAM
i7 950 @ 3.71 Ghz | 1.17v Rampage III Extreme EVGA GTX 580 Corsair Dominators GTX 6gb 1925MHz 7-7-7-20 
Hard DriveOptical DriveOSMonitor
64Gb C300 SATA 6 Gb/s, 2 x 320 Gb F4's RAID 0 ASUS 24x -_- Windows 7 Home(Who needs ultimate?!) ASUS VH226H 21.5 Inch 1080p 
PowerCaseMouseMouse Pad
Corsair HX1000 + Custom Sleeving NZXT Tempest Evo Razer Naga NONE 
  hide details  
Reply
post #8 of 32
Quote:
Originally Posted by Lord Xeb View Post
Onboard Intel RAID controller (AKA my SB). I am going to leave the stripe size default. It is mainly for backup.
You should expect about 100MB/s read and up to 40MB/s writes. This is ofc sequential with 128kb stripe.

I used to have a 4x 2TB array running on an onboard nForce 8300 which was getting about that.

Once switched to a dedicated card (HP SA p410 512MB BBWC) the speeds went up to 150MB/s read and 130MB/s write.

Parity calculation off-loading does wonders
post #9 of 32
Quote:
Originally Posted by Lord Xeb View Post
RAID5 has the parity information spread across all disks, not just put onto one. the RAID your refering to is RAID3
No not necessarily, i noticed you did not mention a RAID card so i assumed that you would be using on board. With an on board, what happens is that the amount of computing power is determined by the CPU RAID controller and minimized. This results in meta data on all drives but minimal parity information on two and most of it on one drive to optimize the CPU overhead.

To harness the full power of RAID 5 you need a controller so you don't have CPU overhead, and so your onboard controller doesnt limit the computation.

Generally i would not recommend RAID 5 with an onboard controller, but since this is for personal use i guess it will have to do.

Source of information: I work at the matrix technology lab at my University.
Bernard
(13 items)
 
  
CPUMotherboardGraphicsRAM
i7 950 @ 3.71 Ghz | 1.17v Rampage III Extreme EVGA GTX 580 Corsair Dominators GTX 6gb 1925MHz 7-7-7-20 
Hard DriveOptical DriveOSMonitor
64Gb C300 SATA 6 Gb/s, 2 x 320 Gb F4's RAID 0 ASUS 24x -_- Windows 7 Home(Who needs ultimate?!) ASUS VH226H 21.5 Inch 1080p 
PowerCaseMouseMouse Pad
Corsair HX1000 + Custom Sleeving NZXT Tempest Evo Razer Naga NONE 
  hide details  
Reply
Bernard
(13 items)
 
  
CPUMotherboardGraphicsRAM
i7 950 @ 3.71 Ghz | 1.17v Rampage III Extreme EVGA GTX 580 Corsair Dominators GTX 6gb 1925MHz 7-7-7-20 
Hard DriveOptical DriveOSMonitor
64Gb C300 SATA 6 Gb/s, 2 x 320 Gb F4's RAID 0 ASUS 24x -_- Windows 7 Home(Who needs ultimate?!) ASUS VH226H 21.5 Inch 1080p 
PowerCaseMouseMouse Pad
Corsair HX1000 + Custom Sleeving NZXT Tempest Evo Razer Naga NONE 
  hide details  
Reply
post #10 of 32
Thread Starter 
Ah okay then I stand corrected. Thanks for the info. Got any recommendedations for an affordable but decent RAID controller that can support at least 3 drives and is PCIe?
 
Gsvlip Dudyrm
(15 items)
 
Oda'maksv
(9 items)
 
CPUMotherboardGraphicsRAM
3770k @ 4.5 1.312 load Zotac Z77 ITX Wifi GTX 1070 Gaming 2126/2249 w/ Hybrid cooler TridentX 16GB 2400MHz 
Hard DriveHard DriveCoolingCooling
Samsung 850 Pro 1TB Seagate 2TB H105 EVGA Hybrid GPU cooler 
OSMonitorKeyboardPower
Windows 10 Asus MG279Q - 24" 144Hz 1080p Filco Majestic II w/ Cherry Reds Seasonic X 760W 
CaseMouseMouse PadAudio
Bitfelix Prodigy Logitech G400 Razer Goliath AKG A701 
AudioAudio
JDS Labs Objective 2 JDS Labs ODAC 
CPUMotherboardGraphicsRAM
Core i5 750 3.99 (190x21) 1.376v Load ASUS P7P55d-E Pro GTX 670 FTW <- Poor overclocker :( 8GB (4x2GB) G.Skill DDR3 1600 
Hard DriveHard DriveOptical DriveOS
Samsung 830 Evo 128GB 2x 2TB  Some DVD drive OSX 10.10.4 
MonitorPowerCaseMouse
Asus 1080P Crap TX 750 HAF 922 G400s 
Mouse PadOther
Apple Keyboard Xbox One controler 
CPURAMHard DriveHard Drive
C2D 2,26GHz under volted @ .978v 8GB  Crucial M4 64GB SSD 500GB Scorpio Black 
OSMonitorKeyboardMouse
OS X 10.0 1280x800 Built-in Trackpad 
Audio
Built-in 
  hide details  
Reply
 
Gsvlip Dudyrm
(15 items)
 
Oda'maksv
(9 items)
 
CPUMotherboardGraphicsRAM
3770k @ 4.5 1.312 load Zotac Z77 ITX Wifi GTX 1070 Gaming 2126/2249 w/ Hybrid cooler TridentX 16GB 2400MHz 
Hard DriveHard DriveCoolingCooling
Samsung 850 Pro 1TB Seagate 2TB H105 EVGA Hybrid GPU cooler 
OSMonitorKeyboardPower
Windows 10 Asus MG279Q - 24" 144Hz 1080p Filco Majestic II w/ Cherry Reds Seasonic X 760W 
CaseMouseMouse PadAudio
Bitfelix Prodigy Logitech G400 Razer Goliath AKG A701 
AudioAudio
JDS Labs Objective 2 JDS Labs ODAC 
CPUMotherboardGraphicsRAM
Core i5 750 3.99 (190x21) 1.376v Load ASUS P7P55d-E Pro GTX 670 FTW <- Poor overclocker :( 8GB (4x2GB) G.Skill DDR3 1600 
Hard DriveHard DriveOptical DriveOS
Samsung 830 Evo 128GB 2x 2TB  Some DVD drive OSX 10.10.4 
MonitorPowerCaseMouse
Asus 1080P Crap TX 750 HAF 922 G400s 
Mouse PadOther
Apple Keyboard Xbox One controler 
CPURAMHard DriveHard Drive
C2D 2,26GHz under volted @ .978v 8GB  Crucial M4 64GB SSD 500GB Scorpio Black 
OSMonitorKeyboardMouse
OS X 10.0 1280x800 Built-in Trackpad 
Audio
Built-in 
  hide details  
Reply
New Posts  All Forums:Forum Nav:
  Return Home
  Back to Forum: Hard Drives & Storage
Overclock.net › Forums › Components › Hard Drives & Storage › What kind of speed should I expect out of RAID5?