Raid stands for redundant array of inexpensive disks. The number of sockets is determined by physical raid controller. Given that block output was fairly close and that there are no parity calculations required for raid10, i would have expected the block rewrite differences between software and hardware to be closer than they are. The xfs filesystem for xfsdefaultnb was created with lazycount1 and mounted with nobarrier. 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. Windows ntfs file system vs xfs linux speed ten forums. It is still software but running on a dedicated controller. I think the key is using enterpriseclass drives, a ups, and really good open source software that is. I recommend ext4 until btrfs catches up in performance, becomes compatible with lilogrub, and gets an fsck tool. Hardware redundant array of inexpensive disks raid and software raid are two main ways for setting up raid system. It is software, but it is a filesystem and storage array wrapped into one.
Btrfsext4xfsf2fs raid 015610 linux benchmarks on four. Everything i say for raid6 vs raid 10 also applies for the zfs equivalent. Hardware raid will cost more, but it will also be free of software raid. Lowend hardware raid vs software raid server fault. You can add one later, but rarely will you need such. What is the difference between hardware and software raid.
Hardware raid or btrfs filesystems best practice to. Id like to provide xfs with a stripe width sw and stripe unit su at mount time for enhanced performance. In a nas device like that, btrfs isnt going to buy you anything. Really you want to talk about dedicated hardware vs cheap software managed hardware vs all software. Cenxfs or xfs extensions for financial services provides a clientserver architecture for financial applications on the microsoft windows platform, especially peripheral devices such as eftpos terminals and atms which are unique to the financial industry. Rather than strip size and stripe size, the xfs man pages use the terms stripe unit and stripe width respectively. Hardware raid or btrfs filesystems best practice to avoid. Generally speaking, operating system treats raid as one disk. Xfs allows specifying the partition raid dimensions to the filesystem, and takes them into consideration with file readswrites, to match the operations. From the same system used as our recent btrfs raid testing, its now time to see how other linux filesystems are performing on the same hardware software setup with a mdadmestablished raid array. A raid can be deployed using both software and hardware. Imho, im a big fan of kernel developers non directly related to zfs, so i really prefere mdadm to hardware raid.
Oct 30, 2015 now, lets see how windows raid0 stacks up to actual hardware raid. Namely, a programs writes to an xfs file system are not guaranteed to be ondisk unless the program issues an fsync call afterwards. An example of a hardware raid device would be one that connects to a scsi controller and presents the raid arrays as a single scsi drive. Nov 03, 2007 so, just for fun i decided to let the raid controller export each disk individually and use the linux software raid and see what performance that would give. It can either be performed in the host servers cpu software raid, or in an external cpu hardware raid. But the real question is whether you should use a hardware raid solution or a software raid solution. Unlike hardware raid, software raid uses the processing power of the operating system in which the raid disks are installed. Not to mention the performance hit under heavy io not having a dedicated hardware controller handling all the striping and parity operations. Raid for everyone faster linux with mdadm and xfs tricks and. As you might know, the data on dynamic volume can be managed either by dedicated computer hardware or software. Generally speaking, raid has socket limitation except for software raid. The same instruction should work on other linux distribution, eg.
It has its own raid implementation raidz and mirroring so you can have redundancy on a software level which is far superior to any other software or hardware raid solution. Zfs would be better compared to md linux software raid lvm xfs or to smartarray hp hardware raid lvm xfs than to xfs alone. Software raid is a type of raid implementation that utilizes operating systembased capabilities to construct and deliver raid services. In cases where rewriting data is a frequent operation, such as running a database server, there can be more than 15% speed gain to using a hardware raid over software. However, windows 10 storage spaces and software raid dont have this limitation. Id stick with xfs and md unless you really, really have a reason to be on the bleeding edge with your storage. Raid1, raid5, raid6, or raid10 is the stuff you should. In still testing the four intel series 530 ssds in a raid array, the new benchmarks today are a comparison of the performance when using btrfs builtin raid capabilities versus setting up a linux 3. Heavy processing can cause some pieces of data to be delayed by a small amount of time. Drive caches are disabled throughout, but the batterybacked cache on the controller is enabled when using hardware raid. 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. Setting up xfs on hardware raid the simple edition percona. At the end as we already ordered the hardware raid we discovered a great improvement 40x. Difference between software raid and hardware raid in high level is presented in this video session.
You can easily move disks from a failed enclosure to a new one, and all your data is preserved. The hardware based array manages the raid subsystem independently from the host and presents to the host only a single disk per raid array. Tips and recommendations for storage server tuning beegfs wiki. The exception to the rule on software raid is xlv under xfs. But with budget favoring the software raid, those wanting optimum performance and efficiency of raid will have to go with the hardware raid.
About 18 months ago i wondered why the xfs faq recommended a stripe width half the number. Feb 28, 2018 raid redundant array of independent disks is one of the popular data storage virtualization technology. Mdadm comparison, the dualhdd btrfs raid benchmarks, and fourssd raid. Oct 25, 2007 really you want to talk about dedicated hardware vs cheap software managed hardware vs all software. Apr 11, 2010 xfs allows specifying the partition raid dimensions to the filesystem, and takes them into consideration with file readswrites, to match the operations.
So, if the disks in hardware raid have different capacities. It is used to improve disk io performance and reliability of your server or workstation. Difference between hardware raid and software raid. Linux file systems are generally fragile enough without throwing software raid and questionable hardware into the mix. 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. Side by side, intel % change vs software raid 0 intel performance increase over microsoft. What is the difference between a software and hardware raid. Setting up xfs on hardware raid the simple edition. Basically correct, but xfs has lots of tuning options to take optimum advantage of the hardware. I only wish that the info in hardware raid specs was more exhaustive. May 24, 2005 scott lowe responds to a techrepublic discussion and one members raid dilemma. You need to think of zfs on solaris vs xfs on top of lvm2 on top of md on top of linux. Two disks, sata 3, hardware raid 0 hardware raid 0.
However, when creating the xfs file system at the end, i got. Following the answer of a very similar question, i hoped for an automatic detection of all necessary parameters. Copied same 4gb mkv from ssd this time in xfs format file to sata hdd although it was 4 x 4 tb raid array in software raid 0 config speed running at average of 784. It also permits users to reconfigure arrays without being restricted by the hardware raid controller. Software v hardware is a lot of pros and cons and you need to kind of assemble a big picture for your scenario. But hardware raid is just software raid on a dedicated controller, so there is nothing inherent one way or the other.
Reading this article woke me up on the issue of bit rot, the undetected changing of single bits to multiple bytes on harddisks in a raid array for now i have our servers running a hardware raid6 of twelve 3gb harddisks each and am looking to improve upon the chance of bit rot not happening, at least not undetected would i be better off using btrfs on 12 jboded harddisks. Here are some tips on raid levels and some feedback on the software vs. Linux and unix zfs vs xfs vs ext4 filesystem is open solaris gonna defend linux. Soft possibly the longest running battle in raid circles is which is faster, hardware raid or software raid. Software raid arrays physical disks in my case, the lvm is an extra layer and its not useful since i only have one physical entity that belongs to a volume group. Implementing raid needs to use either hardware raid special controller or software raid an operating system driver. Raid redundant array of inexpensive disks or redundant array of independent disks is a data storage virtualization technology that combines multiple physical disk drive components into one or more logical units for the purposes of data redundancy, performance improvement, or both. But the real question is whether you should use a hardware raid solution or a software raid. So you could put your filesystem on top of a logical volume, or directly on the raid array device. On top of that it supports a wide range of builtin compression algorithms like lz4 and gzip so you can store your files compressed. Aug 19, 2011 the only xfs parameter you can change at runtime is nobarrier see the source code of xfs s remount support in the linux kernel, which you should use if you have a batterybackup unit bbu on your raid card, although the performance boost seems pretty small on dbtype workloads, even with 512mb of ram on the controller.
It combines multiple inexpensive, small disk drives into an array of disks in order to provide redundancy, lower latency maximizing the chanc. Zfs is scalable, and includes extensive protection against data corruption, support for high storage capacities, efficient data compression, integration of the concepts of filesystem and volume management, snapshots and copyonwrite clones, continuous integrity checking and automatic repair, raid. Hardware raids use the arecas raid 10 for both linux and solaris. The raid 0, 1, 10, 5, and 6 levels were all tested using the builtin btrfs. 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. It uses hardware raid controller card that handles the raid tasks transparently to the operating system. We are using software raid here, so no physical hardware raid card is required this article will guide you through the steps to create a software raid 1 in centos 7 using mdadm.
Btrfs the ext4 filesystem does seem to outperform ext3, xfs and btrfs, and it can be optimized for striping on raid arrays. The drives are configured, so that the data is either divided between disks to distribute load, or duplicated to ensure that it can be recovered once a disk fails. Lets say you have a server with standard hardware raid setup running. Hardware raid may have a battery backup, but unless youre willing to front a good deal of cash, they are slower, and prone to failure. Software raid vs hardware raid hard disk drives hdd. Pretty good for open source software, with software raid, on commodity hardware i have a microatx motherboard in a chinese case, administered by a parttime amateur.
Youd be able to migrate the system to another raid level transparently, so ive set this up at my home as a way to store and secure my personal data photos and stuff but i wouldnt set it. But to appease the powers that be, i have explained the two below hardware raid is when you have a dedicated controller to do the work for you. Linux software raid supports external metadata formats, allowing the use of fake raid. A software raid can also be affected if the host computer is heavily loaded. Recommended raid controller for freebsd 11 4 drives 2tb. Maybe with linux software raid and xfs you would see more benifit.
Jul 15, 2008 in situations where you want to run raid 5 and block output speed is as important as your block input speed, using xfs on a hardware raid is the choice. The only xfs parameter you can change at runtime is nobarrier see the source code of xfs s remount support in the linux kernel, which you should use if you have a batterybackup unit bbu on your raid card, although the performance boost seems pretty small on dbtype workloads, even with 512mb of ram on the controller. Favoring hardware raid over software raid comes from a time when hardware was just not powerful enough to handle software raid processing, along with all the other tasks that it was being used for. If i gather it correctly, a software raid on the fs level, as it is offered by zfs and btrfs is. For block input the hardware wins with 312mbsec versus 240mbsec for software using xfs, and 294mbsec for hardware versus 232mbsec for software using ext3. The cost is lower because no additional hardware raid controller is required. Unless you are buying server grade hardware you dont really know how well. This turns out to be the same as the size formulas i gave above. Its especially able to adopt to the physical layout of a raid system, whether its hardware or software raid.
The all software solution in a custom pc works fine because managing disk volumes doesnt take much cpu time. A redundant array of inexpensive disks raid allows high levels of storage reliability. Linux software raid also supports trim if the underlying disks are ssds, which is virtually unheard of in hardware. With cheaper hardware raid you can also lose data if theres a power outage. Zfs is a combined file system and logical volume manager designed by sun microsystems. 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. I would assume the os to see raid array as one single disk. To put those sidebyside, heres the difference you can expect when comparing hardware raid0 to software raid0. The terms hardware raid and software raid are very misleading as all raid controllers do raid using software. Unlike xfs and hardware raid, btrfs can protect your data on a bit level, see this arstechnica article.
Windows software raid vs hardware raid 10 posts arlesterc. To analyze hardware vs software raid, it is inevitable to talk about the dynamic volume. One of the requirements for the project is that it needs to be on cheap storage as opposed to expensive enterprise sannas. Lets start the hardware vs software raid battle with the hardware side. This makes it possible to decode the otherwise confusing text in the mkfs. You will also have no cheap way to recover data from failed controllers, spare buying the same hardware again. In a hardware raid setup, the drives connect to a raid controller card inserted in a fast pciexpress pcie slot in a motherboard. So, just for fun i decided to let the raid controller export each disk individually and use the linux software raid and see what performance that would give. Zfs combines the functions of filesystem, logical volume manager and software raid, which are handled by independent subsystems under linux. With software raid your data can be split across different enclosures for complete redundancy one can completely stop working and your data is still ok. The quest for the fastest linux filesystem tricks and ticks.
Hardware raid offers better reliability compared to software raid. Put xfs or even well set ext3, lvm2 on top of it, and you have very flexible solution open for expansion in the future. Regardless of which type of raid your system is using either hardware or software. In situations where you want to run raid 5 and block output speed is as important as your block input speed, using xfs on a hardware raid is the choice. Configuring software raid 1 in centos 7 linux scripts hub. And for all the other tests i did software raid outperformed the hardware raid.
Software raid, on the other hand, implements the various raid levels in the kernel disk block device code and. As usual, the optimal settings depend on your particular hardware. Btrfsext4xfsf2fs raid 015610 linux benchmarks on four ssds. Hardware raid and implications for the future duration. Hardware raid 1 we tested quite a few options with various filesystems but always got bad performance on fsync rates tested with pveperf. 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. It is an international standard promoted by the european committee for standardization known by the acronym cen, hence cenxfs. In a hardware raid setup, the drives connect to a special raid controller inserted in a fast pciexpress pcie slot in a motherboard. Nov 06, 2014 from the same system used as our recent btrfs raid testing, its now time to see how other linux filesystems are performing on the same hardware software setup with a mdadmestablished raid array.
A software raid can be prone to data corruption, due to the fault of the raid software or driver that is being used. I have two hardware raid 6 arrays concatenated via lvm. 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. I know my stripe unit size 64k, but what stripe width do i provide. Windows software raid vs hardware raid ars technica. Jul 07, 2009 a redundant array of inexpensive disks raid allows high levels of storage reliability. Linux software raid mdadm testing is a continuation of the earlier standalone benchmarks. This is a method of improving the performance and reliability of your storage media by using multiple drives.
Jul 06, 2011 reasons for using software raid versus a hardware raid setup. Reading this article woke me up on the issue of bit rot, the undetected changing of single bits to multiple bytes on harddisks in a raid array for now i have our servers running a hardware raid6 of twelve 3gb harddisks each and am looking to improve upon the chance of bit rot not happening, at least not undetected. The comparison of these two competing linux raid offerings were done with two ssds of raid0 and raid1 and then four ssds using raid0, raid1, and raid10 levels. Software and hardware raid performance ext3, ext4, xfs. Back then, the solution was to use a hardware raid card with a builtin processor that handled the raid calculations offline. It depends on how you want to manage your data and devices. Raid for everyone faster linux with mdadm and xfs tricks.
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