Does chunk size (stripe size) influence the speed of RAID?
Here you will find out:
- what is chunk size
- how does chunk size influence on RAID 0, 4, 5
- when DiskInternals can help you
Are you ready? Let's read!
What is chunk size (stripe size)?
The RAID chunk size refers to those parts of the strip into which it is divided. In order to get the best array performance, you need to know the correct chunk size and the golden rule for choosing it: small inputs / outputs = large chunk, and large inputs / outputs = small chunk. So, for example, if you are processing photos and images, then the size of the requests will be large. In this case, you will need a small chunk size, because you want to get more bandwidth and ensure that each disk takes up part of the load. In some cases, it will not be possible to determine the size of requests immediately; it will take time to analyze the situation and only then, based on the findings, configure the array with the best performance.
Therefore, if you are not sure about the size of the requests, it is better to take some time to make the right decision.
Chunk size influence on RAID 0, 4, 5
RAID stripe size applies only to certain arrays:
- RAID 0 stripe size
- RAID 4 stripe size
- RAID 5 stripe size
The explanation is simple: stripes are not used for mirroring (RAID 1) or simple concatenation (RAID-linear). The size of the strip itself affects significant processes:
- Delay of writing and reading
- Simultaneously serving of overlapping operation requests
On the Ext2 file system and current kernel read-ahead policies, large sizes always alternate better than small sizes. At the same time, the sizes of interlaces, from a quarter to a full disk cylinder, are standard (the size depends on the disk, since they have recording zones with a different number of sectors and sector caches vary depending on the disk model).
If all disks are already busy reading one file, then an attempt to read several more files at the same time will lead to a conflict. This will naturally degrade performance, as disk ladder algorithms result in searches all over the disk. Therefore, you should know that large bands almost always lead to better performance. However, if you transfer one large file at a time, and the other file requires the highest possible bandwidth, small bands will be more appropriate.
How to recover data from RAID 0, 4, 5 arrays
If you use RAID 0, you can get by with the DiskInternals Uneraser application; it will do an excellent job of recovering files of any type.
If you have RAID 4 or 5, then DiskInternals RAID Recovery is best. The program automatically determines the level of the array, including its basic configurations and characteristics, and restores the maximum amount of lost information. File recovery from a motherboard with RAID support from NVidia, Intel or VIA is also possible. Creating a disk image will always be at your fingertips. Any file found can be viewed before exporting the data for free. The Recovery Wizard will tell you how to do any action during the recovery process, so you can do it if you do not have enough skills. And the recovered data (folders and files) can be exported to local or remote places (including FTP).
Download, install and open RAID Recovery application.
Attach the RAID disks as individual disks.
Run the Wizard, if necessary, and determine the array to scan (the available arrays will be determined automatically; you just need to click on the desired one).
Select the recovery mode: Uneraser, Reader, or Recovery.
Next, you will see the files found on the screen and get read-only access to them. This way, you will see the contents of the files for free.
To export this data, just buy a license and complete the process. It does not take a lot of time!