What is the performance difference between raid10 and raid5?

The difference in performance between raid10 and raid5: 1. The utilization rate of RAID10 is [50%], while the utilization rate of RAID5 is [75%]; 2. The security of RAID10 is higher than RAID5; 3. In continuous In terms of write performance, RAID5 will be better than RAID10.

The difference between raid10 and raid5 performance:

RAID10 is more secure than RAID5 , the higher the space utilization of RAID5.

The specific differences between the two:

1. Comparison in terms of security: RAID10 is more secure than RAID5. Through simple analysis: when disk 1 is damaged, for RAID10, only when the mirror disk corresponding to disk 1 is also damaged will the RAID fail. But for RAID5, if any one of the remaining three disks fails, the RAID will fail.

2. Comparison of space utilization: The utilization rate of RAID10 is 50%, and the utilization rate of RAID5 is 75%. The greater the number of hard drives, the higher the space utilization of RAID5.

3. Comparison of read and write performance: Performance difference in read operations: RAID10 has 4 disks that can read valid data, and RAID5 has 4 disks that can read valid data. The number of disks is also 4 (the parity information is distributed on all disks), so the read performance of the two should be basically the same.

4. Performance difference in continuous writing: During the continuous writing operation, if there is a write cache and there is no problem with the algorithm, RAID5 will be better than RAID10, although maybe There's not much difference. (This assumes that the storage has a certain size, a sufficient write cache, and that the CPU for calculating the check will not be bottlenecked).

Extended information:

RAID5 Store data and corresponding parity information on each disk that makes up RAID5, and parity The parity information and corresponding data are stored on different disks, and complete data is stored on any N-1 disks, which means that there is space equivalent to the capacity of one disk for storing parity information.

Therefore, when a disk in RAID5 is damaged, the integrity of the data will not be affected, thus ensuring data security. When the damaged disk is replaced, RAID will automatically use the remaining parity information to reconstruct the data on the disk to maintain the high reliability of RAID5.

All disks in a raid 5 array must have the same capacity. When the capacities are different, the smallest capacity will prevail. It is best to have the same hard disk speed, otherwise performance will be affected, and available space = number of disks n-1. Raid 5 does not have an independent parity disk. All parity information is scattered on all disks, occupying only the capacity of one disk.

In simple language, use at least 3 hard disks (can be more) to form a RAID5 disk array. When data is written to the hard disk, it is written directly to this hard disk according to the method of 1 hard disk. The tracks of the hard disk, if it is RAID5, the data writing will be divided into 3 parts according to the algorithm, and then written to these 3 hard disks. At the same time, verification information will be written on these 3 hard disks.

When reading the written data, the data content will be read from three hard disks respectively, and then verified through the verification information. When one of the hard drives is damaged, the data content of the third hard drive can be calculated from the data stored on the other two hard drives.

That is to say, the storage method of raid5 only allows one hard disk to fail. When a failure occurs, it needs to be replaced as soon as possible. When a failed hard drive is replaced, the data written during the failure is re-verified. If another block breaks before the fault is resolved, it will be catastrophic.

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