Shulou(Shulou.com)06/02 Report--

RAID technology for storage details 1.RAID technology:

The controller in storage integrates the hard disk according to certain rules, thus speeding up the reading and writing efficiency of the hard disk in storage.

Technical characteristics of 2.RAID

(1) provide redundancy of hard drives in storage

(2) improve the reading and writing efficiency of the hard disk in storage.

3. Common RAID

RAID0

RAID1

RAID5

RAID6

RAID10

RAID01

4.RAID0 technology: improving the efficiency of reading and writing

RAID0 Overview: in storage, the hard disk is divided into many small blocks; in the file, the file is also divided into many small pieces, and then the small pieces of the file are evenly stored in different blocks of the hard disk, so as to improve the reading and writing efficiency of the hard disk.

RAID0 storage mode: when writing data into A1 blocks, the data will be divided into many small blocks and stored evenly in A1 and B1. (if there are more hard drives, the data will be stored evenly in A1 Magi B1 C1. ).

RAID0 disadvantage: there is no redundancy. As long as one hard disk in the storage is damaged, all the data is damaged!

RAID0 use environment: the reading and writing efficiency of the hard disk is very high, and there are no requirements for the reliability and security of the data.

5. RAID1 technology: provide mirroring

RAID1 Overview: also divide the hard disk and files into many small chunks, when writing data to hard disk 1, the corresponding location of hard disk 2 will be mirrored, thus providing redundancy.

RAID1 storage mode: when writing data to A1 block, a mirror is generated in B1 block.

RAID1 disadvantages: improved read performance, but no improvement in write performance.

Advantages of RAID1: mirror image is generated, which improves the security of data, but wastes half the space.

6. RAID5 technology

RAID5 Overview: RAID5 is unique in writing data. If there are 4 hard drives, then when writing data, only write data to 3 hard drives, and then write to the fourth hard disk through some calculation method.

RAID5 storage mode: when the data is stored in A1 block, the data will be divided into many small blocks, which will be evenly stored in A1 Magi B1 C1, and then saved to D1 by some calculation method.

RAID5 features: if the data is stored in 4 hard drives, any one of these four hard drives is broken, the data in the damaged hard disk can be recovered through the data in the remaining 3 disks.

RAID5 advantages: improve read efficiency, but write efficiency is relatively poor, but also provide redundancy, up to a maximum of 1 bad hard disk. If 2 hard drives are broken, all the data in the storage will be lost!

The disadvantage of RAID5: wasted 1Pay's space, n = the number of hard disks in storage.

Big disadvantage of RAID5: when RAID5 breaks down any hard drive, the overall performance will degrade sharply! The reason is that when a hard disk is damaged, if you want to read the data of that hard disk, you need to calculate it in the rest of the hard disk.

7. RAID6 (the popularity is OK)

RAID6 Overview: the mechanism of RAID6 is the same as that of RAID5. Suppose there are four hard drives, the data will be written on two hard drives, and then some calculation will be used to write the data to the remaining two hard drives. So RAID6 provides redundancy and allows 2 hard drives to break. When three hard drives are damaged, all data in the storage is corrupted.

Pros and cons of RAID6: it increases the read rate, but the write rate is worse than RAID5. Redundancy is provided, allowing 2 hard drives to be broken. Wasted 2 percent of space, where n = the total number of hard drives.

Important disadvantage of RAID6: when RAID6 destroys 1 hard drive, the performance degradation is not obvious. When RAID6 breaks down two hard drives, performance, like RAID5, degrades sharply.

8. RAID01 (popular)

RAID01 Overview: RAID01 actually combines the advantages of RAID0 and RAID1. The first two hard drives do RAID0, thus improving the reading and writing efficiency, forming a hard disk group, and making two hard disk groups into a RAID1 to achieve redundancy.

RAID01 advantages: achieve read and write performance improvement and redundancy.

RAID01 shortcomings, serious waste of space, wasted 50%.

9. RAID10 (popular)

RAID10 Overview: the situation of RAID10 is similar to that of RAID01. First, two hard drives are RAID1 to form two hard disk groups to achieve redundancy, and then two hard disk groups are RAID0 to improve the read and write efficiency of the hard disk.

RAID10 advantages: achieve read and write performance improvement and redundancy.

RAID10 shortcomings, serious waste of space, wasted 50%.

10. Summary of RAID application

RAID0 improves the efficiency of reading and writing, and RAID1 provides redundancy.

RAID5 allows you to break one hard drive, and RAID6 allows you to break two hard drives. RAID5 and RAID6 allow for a sharp drop in performance when the last hard drive is damaged.

RAID10 and RAID01, which combine the characteristics of RAID1 and RAID0, are now the most popular and are also recommended. But RAID10 and RAID01 waste a lot of space.

-end-

Welcome to subscribe "Shulou Technology Information " to get latest news, interesting things and hot topics in the IT industry, and controls the hottest and latest Internet news, technology news and IT industry trends.