Linux software raid benchmarks

In the case of mdadm and software raid0 on linux, you cannot grow a raid0 group. To see why the rewrite test is important on a parity raid, imagine that you are creating a raid5 using linux software raid on four disks. You can benchmark the performance difference between running a raid using the linux kernel software raid and a hardware raid card. Raid 5 is so bad it should never, ever be used today.

In testing both software and hardware raid performance i employed six 750gb samsung sata drives in three raid configurations 5, 6, and 10. How to set up software raid 0 for windows and linux pc gamer. Latest software can be downloaded from megaraid downloads to configure the raid adapter and create logical arrays use either ctrlh utility during bios post use megaraid storage manager msm running from os. The software raid10 driver has a number of options for tweaking block layout that can bring further performance benefits depending on your io load pattern see here for some simple benchmarks though im not aware of any distributions that support this for of raid 10 from install yet only the more traditional nested arrangement. Linux software raid linux kernels md driver also supports creation of standard raid 0, 1, 4, 5, and 6 configurations. Mdadm is linux based software that allows you to use the operating system to. Linux software raid mdadm testing is a continuation of the earlier standalone benchmarks. Creating a software raid array in operating system software is the easiest way to go. More importantly, raid has welldefined availability goals, making it an ideal candidate application for benchmarking availability. Mdadm is linux based software that allows you to use the operating system to create and handle raid arrays with ssds or normal hdds. Theres nothing inherently wrong with cpuassisted aka software raid, but you should use the software raid that. In general, software raid offers very good performance and is relatively easy. Windows 8 comes with everything you need to use software raid, while the linux package. Ive got a new system on order from the egg set to replace my hacked together homeserver.

How to use mdadm linux raid a highly resilient raid solution. For what its worth, i run software raid on my box at home because for my home environment it really does have the best cost benefit. There is some general information about benchmarking software too. In this article are some new details on kq infotechs zfs kernel module and our results from testing out the zfs filesystem on linux. The problem is that, in spite of your intuition, linux software raid 1 does not use both drives for a single read operation. This is because a copy of the data must be written to. A lot of linux benchmarks ive seen demonstrate things such as encoding with lame. Software linux raid 0, 1 and no raid benchmark osnews. Written by michael larabel in storage on 15 august 2016.

Raid 5 benchmarks, raid 5 performance data from and the phoronix test suite. Using raid 0 it will save as a in first disk and p in the second disk, then again p in first disk and l in second disk. We find that the availability benchmarks are powerful enough not only to quantify the impact of various failure conditions on the avail. Then e in first disk, like this it will continue the round robin process to save the data. My own tests of the two alternatives yielded some interesting results. I dont know if that example holds any water for a servergrade test. Creating software raid0 stripe on two devices using. My old system consists of 5 drives, individual partitions with a mix partitions, file system types and purposes. As the linux software raid howto says, the combination of chunk size and block size matters for your performance.

The tests were performed on a transtec calleo appliance see the test hardware box with eight fast disks in a raid level 0 array with a stripe size of 64kb. To get a speed benefit, you need to have two separate read operations running in parallel. One thing i would like to do in the future when i have more disks is to rerun these benchmarks on a raid 5 array and vary the chunk size. Towards availability and maintainability benchmarks. The results of the benchmarks in this article could help readers choose the most appropriate filesystem for the task at hand. The goal of this study is to determine the cheapest reasonably performant solution for a 5spindle software raid configuration using linux as an nfs file server for a home office. Raid 10 layouts raid10 requires a minimum of 4 disks in theory, on linux mdadm can create a custom raid 10 array using two disks only, but this setup is generally avoided. Raid 6 also uses striping, like raid 5, but stores two distinct parity blocks distributed across each member disk. Benchmark raid 5 vs raid 10 with and without hyperx. We can use full disks, or we can use same sized partitions on different sized drives. Also, it is not unusual to find software raid underlying. Raid 6 requires 4 or more physical drives, and provides the benefits of raid 5 but with security against two drive failures. Reading a single large file will never be faster with raid 1.

In the event of a failed disk, these parity blocks are used to reconstruct the data on a replacement disk. This has been well established even since the 90s that you want mirrored raid only for databases. The recommended software raid implementation in linux is the open source md raid package. The information is quite dated, as can be seen from both the hardware and software specifications.

Fio read tests showed raid1 with both 2 and 4 disk configurations performing much better than the btrfs builtin raid1 functionality. We apply the methodology to measure the availability of the software raid systems shipped with linux, solaris 7 server, and windows 2000 server, and find that the methodology is powerful enough. The drives used for testing were four ocztoshiba trion 150 120gb ssds. Raid can be created, if there are minimum 2 number of disk connected to a raid controller and make a logical volume or more drives can be added in an array according to defined raid levels. Unfortunately you need to be a member to get hold of the software which is proced up to tier 1 hardware vendor levels. Each raid mode provides an enhancement in one aspect of data management. For a raid 1 array this doesnt matter since there is no chunk size to deal with. I use software raid 5, and linux benchmarks its algorithms at runtime for calculating the parity information in order to pick the best one.

I have not done any benchmarks myself so i cannot comment further on that. There is some general information about benchmarking software. Software raid how to optimize software raid on linux. A single drive provides a read speed of 85 mbs and a write speed of 88 mbs. This list of linux benchmark scripts and tools should prove useful for quick performance check of cpu, storage, memory and network on linux servers and vps.

The controller is not used for raid, only to supply sufficient sata ports. This section contains a number of benchmarks from a realworld system using software raid. Contains comprehensive benchmarking of linux ubuntu 7. However, the raid10 functionality with btrfs seemed to perform much.

This machine will primarily be used for in no particular order av storage entire cd. Using mdadm linux soft raid were ext4, f2fs, and xfs while btrfs raid0 raid1 was also tested using that filesystems integratednative. Linux benchmark scripts and tools last updated may 31, 2019 published april 6, 2019 by hayden james, in blog linux. A lot of software raids performance depends on the. Lets start the hardware vs software raid battle with the hardware side. Intel has enhanced md raid to support rst metadata and orom and it is validated and supported by intel for server. Benchmark samples were done with the bonnie program, and at all times on files twice or more the size of the physical ram in the machine. This means that you cant add drives to an existing raid0 group without having to rebuild the entire raid group but having to restore all the data from a backup. Benchmarking linux filesystems on software raid 1 lone. The operating system will see all the disks individually, then present a new raided volume to. In general, software raid offers very good performance and is relatively easy to maintain. Unless software raid and linux io options in general start advancing at an absurd rate, there will remain a market for real enterprise storage technologies for a long, long time. In this article are some ext4 and xfs filesystem benchmark results on the four drive ssd raid array by making use of the linux md raid. All drives are attached to the highpoint controller.

Linux does have drivers for some raid chipsets, but instead of trying to get some unsupported, propietary driver to work with your system, you may be better off with the md driver, which is opensource and well supported. Linux disks utility benchmark is used so we can see the performance graph. 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. It is easy to find raid information elsewhere, but here are my thoughts. Phoronix takes a brand new, unstable zfs linux kernel module and benchmarks it agains btrfs, zfsfuse, ext4, and xfs with interesting results. Linux benchmarking tools closed ask question asked 10 years. We just need to remember that the smallest of the hdds or partitions dictates the arrays capacity. I think in hardware raid, if the hardware fails on the raid, you need the exact copy of the hardware to recover the data, i. Must wait for the write to occur to all of the disks in the mirror. Software raid are available without using physical hardware those are called as software raid. Normal io includes home directory service, mostlyreadonly large file service e.

Want to get an idea of what speed advantage adding an expensive hardware raid card to your new server is likely to give you. From this we come to know that raid 0 will write the half of the data to first disk and other half of the data to second disk. In a hardware raid setup, the drives connect to a raid controller card inserted in a fast pciexpress pcie slot in a motherboard. Depending on the failed disk it can tolerate from a minimum of n 2 1 disks failure in the case that all failed disk have the same data to a maximum of n 2 disks. Motherboard raid, also known as fake raid, is almost always merely biosassisted software raid, implemented in firmware and is closedsource, proprietary, nonstandard, and often buggy, and almost always slower than the timetested and reliable software raid found in linux. 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. Software raid does not require any special raid card, and is handled by the operating system. As the comments on my recent post apples new kickbutt file system showed, some folks cant believe that software raid could be faster than a. Some raid 1 implementations treat arrays with more than two disks differently, creating a nonstandard raid level known as raid 1e. The raid will be created by default with a 64 kilobyte kb chunk size, which means that over the four disks there will be three chunks of 64kb and one 64kb chunk being the parity, as shown in the diagram. In this layout, data striping is combined with mirroring. This software raid solution has been used primarily on mobile, desktop, and workstation platforms and, to a limited extent, on server platforms. Ive personally seen a software raid 1 beat an lsi hardware raid 1 that was using the same drives.