Raid redundant array of independent disks is one of the popular data storage virtualization technology. The md driver in the linux kernel is an example of a raid solution that is completely hardware independent. I am trying to build a raid array only for reliability. What is exactly the difference and bads and goods of both sides software raid vs hardware raid.
Hardware raid has the ability to take a group of drives and make it appear as a single drive. Imho, im a big fan of kernel developers non directly related to zfs, so i really prefere mdadm to hardware raid. I would give zfs a slight performance edge, but only because the question really comes down to hw raid battery backed cache vs zfs l2arczil. Software raid6 vs hardware all i can find is vague, conflicting comments with nothing to back them up. Is there any performance increase from using the raid supported by the motherboard. It is used to improve disk io performance and reliability of your server or workstation. I have been using raid in linux for many years using mdadm, which is. Hardware raid will cost more, but it will also be free of software raid s.
We can use full disks, or we can use same sized partitions on different sized drives. Software raid vs hardware raid differences explained. This is a method of improving the performance and reliability of. By definition, fake raid has no inherent benefits over honest software raid, they share all hardware and the os people have better watch over the implementations. A hp server that i work on had two disks in a raid1 array, one of my colleagues added an extra disk and made it a raid5, the hardware raid device moved the data around as appropriate while the machine was running and the disk space was expanded without any downtime. It uses hardware raid controller card that handles the raid tasks transparently to the operating system.
I am wondering if anyone has done any benchmarks or tests regarding the performance difference of 2 ssd raid1 on software raid vs hardware raid. It is a way to virtualize multiple, independent hard disk drives into one or more arrays to improve performance, capacity and reliability. It should replace many of the unmaintained and outofdate documents out there such as the software raid howto and the linux raid faq. But with budget favoring the software raid, those wanting optimum performance and. Want to get an idea of what speed advantage adding an expensive hardware raid card to your new server is likely to give you. Oct 30, 2015 while the intel raid controller blows the software raid out of the water on sequential reads, surprisingly the windows software raid was better in nearly every other respect.
From a pure operations perspective, there is very little difference between hardware and software raid. Your best bet for raid on linux is either to stick with the software raid which works ok or to move to an enterprise grade server with. It can either be performed in the host servers cpu software raid, or in an external cpu hardware raid. With its far layout, md raid 10 can run both striped and mirrored, even with only two drives in f2 layout. It is going to be for low performance file serving so performance is not a big issue, only reliability. Software raid, on the other hand, implements the various raid levels in the kernel disk block device code and.
Before raid was raid, software disk mirroring raid 1 was a huge profit generator for system vendors, who sold it as an addon to their operating systems. Software vs hardware raid performance and cache usage. Hardware raid is handled by a specialized raid controller card which does its own processing to make many devices act like one. You can benchmark the performance difference between running a raid using the linux kernel software raid and a hardware raid card. It combines multiple inexpensive, small disk drives into an array of disks in order to provide redundancy, lower latency maximizing the chanc. With the advent of hardware raid systems the battle was joined until the hardware array emerged victorious. Software vs bios vs hardware raid ars technica openforum. We list the pros and cons of hardware vs software raid to help you decide. Aug 14, 2018 raid stands for redundant array of inexpensive disks. There are 2 major types of raid controllers including software and hardware raid.
Software raid has been relegated to lowend, lowcost applications where folks. There will likely be more advanced features, such as drives being hotswappable in case of failure. This is hardware raid and, honestly, im guessing it is slower than software raid if really tested, it lack the horsepower to anything much. Differences between hardware raid, hbas, and software raid.
So, what are the pros and cons of software raid vs. Flexibility is the key advantage of an open source software raid, like linux mdadm. Favoring hardware raid over software raid comes from a time when. On the software side, todays software raid is superfast at least with linux and. So raid is kind of a method for improving the performance and reliability of your storage media by using multiple drives. We list the pros and cons of hardware vs software raid to help you decide which one is best for you.
Another limitation of linux software raid is expanding raid groups. Whether or not youre looking to set up your own server, optimize the performance of your data storage solution, or just make sure youre protected as best you can be against data loss, a raid solution is going to come in handy. The performance of a softwarebased array depends on the server cpu performance and load. My experience with hardware and fakehardware raid is that as long as you stay with the same vendor, the raid metadata will be recognized ive seen this when moving drives between various hp, areca and lsi hardware raid controllers, and with intel, amd and even via hostraid i was pretty surprised when i connected a 250gb hard drive from some old amd desktop box to a hp g1 microserver, and. While the intel raid controller blows the software raid out of the water on sequential reads, surprisingly the windows software raid was better in nearly every other respect. Different types of raid controllers support different raid levels. So if i recall correctly, software raid would for an example is to be utilizing a intel option rom raid controller. The basic idea of raid redundant arrays of inexpensive disks is to combine multiple small, independent disk drives into an array of disk drives which yields performance and recoverability exceeding that of a single large expensive drive sled. This integration is really what has allowed software raid to dramatically outpace hardware raid. It is generally fine, however, to use windows software raid on simple storage. Nov 16, 2007 another limitation of linux software raid is expanding raid groups. Feb 28, 2018 raid redundant array of independent disks is one of the popular data storage virtualization technology. A raid can be deployed using both software and hardware. I have scoured through articles written about tuning software and i have used linux software raid for over 10 years.
What is the difference between a software and hardware raid. Jul 07, 2009 a redundant array of inexpensive disks raid allows high levels of storage reliability. While you might think the computer you are using is the most important part of your everyday and professional workflows, there is. Someone told me that linuxs software raid was less reliable than hardware raid. This site is the linux raid kernel list communitymanaged reference for linux software raid as implemented in recent version 4 kernels and earlier. This card is either configured through bios extensionsyou may get an extra hit esc to setup message on boot or through proprietary utilities. The raid can be implemented either using a special controller hardware raid, or by an operating system driver software raid. A redundant array of inexpensive disks raid allows high levels of storage reliability. While a file server setup to use software raid would likely sport a quad core cpu with 8 or 16gb of ram, the relative differences in performance. Comparing hardware raid vs software raid setups deals with how the storage drives in a raid array connect to the motherboard in a server or pc, and the management of those drives. Hardware redundant array of inexpensive disks raid and software raid are two main ways for setting up raid system.
In a hardware raid setup, the drives connect to a special raid controller inserted in a fast pciexpress pcie slot in a motherboard. Synology diskstation ds, buffalo terastation, are examples. What if one disk fails, will software raid still allow. Your best bet for raid on linux is either to stick with the software raid which works ok or to move to an enterprise grade server with an integrated raid controller and supported disks. Unfortunately sgi did not put xlv support into the linux xfs. The performance of a softwarebased array is dependent on the server cpu performance and load. Software vs hardware raid performance and cache usage server. In my case the setup will be used for a website doing heavy io readwriteimages with a big db. A hp server that i work on had two disks in a raid 1 array, one of my colleagues added an extra disk and made it a raid 5, the hardware raid device moved the data around as appropriate while the machine was running and the disk space was expanded without any downtime. What are the differences between the different raid levels. So it looks like hardware raid 10 is the winner for windows setup providing you can replace the card in event of failure, and software raid 10 is a viable option for linux etc. My own tests of the two alternatives yielded some interesting results. The linux software raid stack is just as much of a component as a hardware card, and its failure modes are numerous and amusing except when you get hit by. It is usually os agnostic, so volumes are not specific to an os file system like software raid.
Where that processing occurs can be important depending on the complexity of your raid setup. Standard raid levels include raid 0, raid 1, raid 2, raid 4, raid 5, raid 6, raid 10, etc. Boosts system performance for backups and restoration, especially in. Or raid 1 if you only need the speedcapacity of a single pair. Software raid is a type of raid implementation that utilizes operating systembased capabilities to construct and deliver raid services. Software raid also works with cheaper ide disks as well as scsi disks. Aug 15, 2006 before raid was raid, software disk mirroring raid 1 was a huge profit generator for system vendors, who sold it as an addon to their operating systems. A brief history of raid raid has been around since 1970s 1989 berkeley paper was a taxonomy 1989 witnessed the first raid5 in software 1990s saw many hardware raid3, 5s lsi, 3ware, maxstrat, highpoint, intel 1990s also saw the introduction of raidframe mdraid came along in 2001. For software raid i used the linux kernel software raid functionality of a system running 64bit fedora 9. Apr 05, 2019 hardware raid has the ability to take a group of drives and make it appear as a single drive. Software raid, as you might already know, is usually builtin on your os and unlike a hardware raid, you will need to spend a little extra on a controller card. With hardware raid, because the processing work is done on a discrete controller card in the server or at the level of the storage subsystem, theres no added load to the server processor and buses. When running basic io tests ddoflagdirect 5k to 100g files, hdparam t, etc.
However this also fundamentally precludes integration of features into the os and file system. The reason for this is the performance you can get out of an xlv on xfs. Someone told me that linux s software raid was less reliable than hardware raid. How to create a software raid 5 in linux mint ubuntu. Hardware raid is mostly used by the application to scale up the availability and performance whereas software raid is mostly suited for the workstation with limited data storage requirements and. Those tests were done using the btrfs builtin raid capabilities while today are some comparison tests against those numbers when using the linux software raid setup via mdadm. Comparison of software raid on windows versus linux by angsuman chakraborty, gaea news network sunday, february 18, 2007. My experience with hardware and fake hardware raid is that as long as you stay with the same vendor, the raid metadata will be recognized ive seen this when moving drives between various hp, areca and lsi hardware raid controllers, and with intel, amd and even via hostraid i was pretty surprised when i connected a 250gb hard drive from some old amd desktop box to a hp g1 microserver, and. Bsd opensolaris and linux raid software drivers are open source. With zfs you can move that l2arc and zil to fast ssd or nvme drives which are much larger and hence the edge.
Raid stands for redundant array of inexpensive disks. Windows software raid has a bad reputation, performance wise, and even storage space seems not too different. Comparison of software raid on windows versus linux. We just need to remember that the smallest of the hdds or partitions dictates the arrays capacity. Windows software raid vs hardware raid ars technica. With todays fast cpus, software raid performance can excel against hardware raid. Jun, 2016 comparing hardware raid vs software raid setups deals with how the storage drives in a raid array connect to the motherboard in a server or pc, and the management of those drives. Usually, hardware raid has better performance with the advanced raid levels than software raid. The linux kernel contains an md driver that allows the raid solution to be completely hardware independent. But the real question is whether you should use a hardware raid solution or a software raid solution. Beyond that, hardware raid usually has at least options for battery backed or newer capacitorflash based write caches. Mar 14, 20 by definition, fake raid has no inherent benefits over honest software raid, they share all hardware and the os people have better watch over the implementations.
The performance of a software based array depends on the server cpu performance and load. Software raid 6 vs hardware all i can find is vague, conflicting comments with nothing to back them up. The linux software raid stack is just as much of a component as a hardware card, and its failure modes are numerous and. Better performance, especially in more complex raid configurations. Difference between hardware raid and software raid. Smbs using nas devices for backup and restore purposes will find many softwareraid based options. It seems that no matter if you use a hardware or a software raid controller, you should expect to lose performance when youre duplicating every write, which makes sense. Comparing hardware raid vs software raid deals with how the. Ultimately, the difference comes down to where the raid processing is performed. Apr 14, 2020 there are 2 major types of raid controllers including software and hardware raid.
With todays faster cpus, software raid outperforms hardware raid. Linux md raid is exceptionally fast and versatile, but linux io stack is composed of multiple independent pieces that you need to carefully understood to extract maximum performance. What is the difference between hardware raid and software. Regular raid 1, as provided by linux software raid, does not stripe reads, but can perform reads in parallel. Ive been hoping other people would post with some experience, because im in the middle of a decision and am leaning toward software but just basically fear the unknown. We have privately tested linux kernel raid versus popular professional. Hardware raid will cost more, but it will also be free of software raids. Whether software raid vs hardware raid is the one for you depends on what you need to do and how much you want to pay. But with budget favoring the software raid, those wanting optimum performance and efficiency of raid will have to go with the hardware raid.
Software vs hardware raid nixcraft nixcraft linux tips. I do agree though, that hardware raid is the best choice on business class windows servers or even important. So if iorom is software, and if i recall correctly linux os raid is hardware raid and therefore if iorom software raid fails you lose all data but with linux os hardware raid if the raid is lost, your data is recoverable. The advantage of hardware raid is performance, plain and simple. In testing both software and hardware raid performance i employed six 750gb samsung sata drives in three raid configurations 5, 6, and 10. Nov 15, 2019 hardware raid handles its arrays independently from the host and it still presents the host with a single disk per raid array.
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