Hi Team,
I want to understand how exactly the space reclamation job works and why do we need it when we have Data Aging.
What is the Data verification and how it works in the background.
Thanks.
Answer
Space reclamation and Data verification
+1Best answer by Damian Andre
So will the same works for Micro pruning and Macro pruning as well??
No it does not. Macro pruning is about deleting the whole chunk file. Every block needs to be prunable for macro pruning to take place. Generally macro pruning is never done with deduplication unless something has gone wrong :-)
+23- Vaulter
The data aging job removes no data, its a logical job that calculates which jobs become eligible for pruning based on their retention settings. Once a job becomes aged, there are a few triggers in the software that will start the processing of the physical deletes.
Space reclamation is only required if your storage does not support sparse files. HyperScale X falls into this category, as well as some older NAS devices or other weird and wonderful file systems that folks like to use to store data.
Sparse files allow us to delete data from any spot within a file, but not the file itself. Since a file/chunk could be 1MB in size, and we only need to delete a single 128K block, file system sparse support is required to delete the specific 128K range of data in the file.
If sparse is not supported by the disk library file system, we can only truncate the ends of the file but cannot reclaim space in the middle - this is where space reclamation comes in.
Its a process that allows us to read the file/chunk, discard the data that we no longer need, and then rewrite the file/chunk as new sans the deleted blocks. Its much more intensive which is why there are various levels to pick from, which is a trade off of performance vs reclaimed space.
+1
So will the same works for Micro pruning and Macro pruning as well??
+23- Vaulter
- Answer
So will the same works for Micro pruning and Macro pruning as well??
No it does not. Macro pruning is about deleting the whole chunk file. Every block needs to be prunable for macro pruning to take place. Generally macro pruning is never done with deduplication unless something has gone wrong :-)
Enter your E-mail address. We'll send you an e-mail with instructions to reset your password.