lsi jbod

The MD and DM modules under Linux:MD (Multiple devices):A Btrfs filesystem can be created on top of many devices, and more devices can is added after the FS have been created.By default, metadata'll be mirrored across-devices and data would be striped across all of the devices present.If only one device is present, metadata'll be duplicated on the that one device.DM (device Mapper):Device Mapper is a universal device mapping mechanism in the Linux2.6 kernel that supports logical volume managemen

Continuous OPEN-E DSS V7 application series six building software iSCSIFirst, the basic introductionUnit (Units): physical hard disk or RAID array. DSS with S0,S1, ..., s[x] represents the Sata/jbod/raid unit, with H0,H1, ..., H[x] on behalf of the IDE unit, with MD0,MD1, ..., Md[x] on behalf of the software raids. You can set up a volume group in a unit, or you can add a new unit to an existing volume group. DSS can only a

on the Advanced blade server that connects the fibre storage network. Even Microsoft Exchange began recommending the evolution from RAID to JBOD, which instead relied on the application layer for fault tolerance.Let's take a closer look at the three requirements of enterprise-class OpenStack.Scalability and Performance (Scalability performance)Scalability is a feature of the system's ability to meet growing system size and load requirements. Perform

the moment, RAID is not a significant cost-saving function, but raid can take advantage of multiple hard drives to achieve speed and throughput far beyond any single hard drive. In addition to performance improvements, RAID can provide good fault tolerance and can continue to work without any problem with any hard drive, and will not be affected by damage to the hard drive.RAID technology is divided into several different levels, each of which offers different speeds, security and cost-performa

that is closer to 0, so that when my memory runs out, I try to turn on a small percentage of swap, which can cause the broker to become very slow, but at least gives the user the opportunity to identify the problem and deal with it.Fifth JVM heap size. first of all, in view of the current Kafka new version already does not support JAVA7, and Java 8 itself is not updated, and even Java9 actually do not do, directly do Java10, so I suggest Kafka at least with Java8 to build. As for the size of th

1. What is RAID0? RAID0, which divides data into several halves and writes data to multiple disks A: A1 A2 ...... Performance improvement. At least two disks are required. Merge multiple disks into a large disk with no redundancy and parallel I/O, with the fastest speed. RAID 0 is also called a zone set. It associates multiple disks to form a large disk. When storing data, the data is segmented by the number of disks and written into these disks at the same time. Therefore, RAID 0 is the fastes

NraidNraid is non-raid. The capacity of all disks is combined into a logical disk without data block entries (no block stripping ). Nraid does not provide data redundancy. At least one disk is required.JbodJbod stands for just a bunch of drives. The disk controller regards each physical disk as an independent disk, so each disk is an independent logical disk. Jbod does not provide data redundancy. At least one disk is required.Raid 0Raid 0 is data str

parallel to increase the speed of access to the disk, many disk drives can transmit data simultaneously, and these disk drives are logically a disk drive. So using RAID can reach the rate of a single disk drive several times. Because the CPU is growing fast, and the data transfer rate of disk drives cannot be greatly improved, a solution is needed to resolve the contradiction between the two.(2) Higher security. Compared to ordinary disk drives, many RAID modes provide a variety of data repair

(Figure 1, 2). Just for many friends, in order to use the old hard drive to buy a new motherboard is not realistic, based on existing hardware to play their greatest effect is their pursuit, so the following is a brief introduction to the formation of SATA and pat a interface hard disk hybrid RAID System topic. The first thing to say is that building such a hybrid RAID system can make your old hard drive a new life, but there are some risks and pitfalls: First of all, the parameters of the t

array, or it can be a collection of unprotected storage (JBOD). *************************************************************************************************************** *********************************************************************************Asmlib and UdevBoth Asmlib and Udev solved the problem of fixed device names. In Linux, the order in which devices are detected and enumerated is not fixed. This is not the same as in Solaris, for

inexpensive to store.RAID 6RAID 6 adds a second independent parity information block compared to RAID 5. Two independent parity systems use different algorithms and the reliability of the data is very high, and any two disks fail at the same time without compromising data integrity. RAID 6 requires more disk space to be assigned to parity information and additional checksum calculations, with more IO operations and computations compared to RAID 5, and its "write performance" strongly depends on

. About BL2 startup process: BL2 copies the OS image (BL3) to the DDR and then checks the integrity of the OS image. In BL2, the system clock is initialized and the DDR is initialized. If necessary, uart, net, emmc, and sdcard can also be initialized. The Process Code in BL2 does not depend on BL1, that is, BL2 will no longer go back to call the BL1 process. The starting process of each phase is basically like this. Next we will introduce how to divide each segment of the internal memory in

1. Login to VCenter via VSphere client. Go to the VM2. Create a 1G new disk (SCSI 1:2) for the VM temperary3. Change SCSI controller1 to paravirtual from Logical LSI SAS4. Boot VM, and upgrade VMtools5. Shutdown the VM6. Remove the new disk (SCSI 1:2) and SCSI controller1 'll be removed automatic7. Change SCSI Controller0 to paravirtual from Logical LSI SAS8. Change options mem/cpu HotPlug to enable9. Remov

Disk array is a long-standing technology on the server, it is widely used by most server OEMs to make reasonable use of space and performance in different array modes to match the cost-effective disk array. Among them, LSI Company's MegaRAID SAS products are widely used in various brands (except HP) x86 servers.Why is there a cache?Array Card core technology consists of three parts: 1, Data stripe, 2, data redundancy, 3, cache. Where the cache is know

design, 25MHz)LSE (OSC): External low-speed crystal (default is 32.768KHZ)LSI (RC): Internal low-speed crystal oscillator, ~40khzPLLCLK: Locked loop multiplier output, maximum frequency less than 72MHz, note: pllclk source HSE,HSE/2,HSI/2(2) System clock SourceSYSCLK: System clockSOURCE Hsi,pllclk,hse, if the CSS (Clock monitoring System) detects a HSE failure, SYSCLK = HSI;(3) Main output clock sourceHCLK: High performance bus clock (sysclk via AHB

Code Cache 4X32KB 8-Way Collection Association L1 Data Cache 4X32KB 4-Way Collection Association L2 Cache 4X256KB 8-Way Collection Association L3 Cache 8MB 16-Way Collection Association Server Board Motherboard model HP ProLiant DL120 G7 Motherboard chipset HP ProLiant DL120 G7 North Bridge chip characteristics 2xQPIVt-d

= "image" Src= "http://s3.51cto.com/wyfs02/M02/6C/B7/wKiom1VQaaHyFW2nAADR6x6UQug607.jpg" width= "608" height= "388"/>650) this.width=650; "title=" image "style=" border-right-width:0px;border-bottom-width:0px;border-top-width:0px; " Border= "0" alt= "image" Src= "http://s3.51cto.com/wyfs02/M00/6C/B7/wKiom1VQaaawNypoAAFTbUvxjgQ223.jpg" width= "607" height= "444"/>650) this.width=650; "title=" image "style=" border-right-width:0px;border-bottom-width:0px;border-top-width:0px; " Border= "0" alt= "i

, 0.35355339059327373), (7, 0.35355339059327373)], [(8, 0.18147115159841573), (9, 0.49169813431045906), (10, 0.49169813431045906), (11, 0.49169813431045906), (12, 0.49169813431045906)], [(8, 0.2084041054460164), (13, 0.5646732768699807), (14, 0.5646732768699807), (15, 0.5646732768699807)]]Obviously, the length of the sentence is different, so the dimensions of the TFIDF vector are different. So how do we do this? --You can use LSI vectors to e

1. In stm32, there are five clock sources:HSI,HSE,LSI,LSE,PLL. ①HSIIt is a high-speed internal clock, RC oscillator, and the frequency is 8 MHz. ②HSEIt is a high-speed external clock, which can be connected to a Z/Ceramic Resonator or an external clock source. The frequency range is 4 MHz ~ 16 MHz. Generally, it is connected to 8 MHz. ③LSIIt is a low-speed internal clock, RC oscillator, and the frequency is 40 kHz. ④LSEIt is a Z crystal with a low-spe

improvements and optimizations make the relevant hardware more outstanding in the Red Flag Advanced Server 4.1 for IBM pSeries system, including: IBM ServeRAID Ibm ppc Linux RAID Adapter Network Bonding Serial ATA Adaptec RAID LSI Logic RAID LSI Logic MPT Fusion Compaq SA53xx Controllers QLogic Fib