Summary : SharePoint 2013 Shredded Storage – How it Works,How does Shredded Storage works in SharePoint 2013
A new feature of SharePoint 2013, “Shredded Storage” is being loved Everywhere.In this post we explain in detail how it actually works in SharePoint 2013.
Firstly, a Short Description about Shredded Storage.
What is Shredded Storage?
Its a new Feature Introduced in SharePoint 2013 where Documents and Changes to the Documents are stored as “Shredded BLOBS”.Unlike SharePoint 2010, it helps to lower down the amount of storage required for saving files by saving only the Changes and not the entire Versions of the Files in database.
Now Let me Introduce you to some new additions that were made to support Shredded Storage.
1. DocStreams Data Table – DocStreams is a new data table that gets created with each new Content database.This table contains File Blobs also known as “Shredded BLOBS” in individual rows.
2. BLOB Cache – As in SharePoint 2010 BLOB Cache enables a farm administrator to control the size of incremental reads when a client requests a file.
3. BLOB Index – Blob Index keeps track of Various shreds and its his duty to make sure that a file can be reassembled when it is requested.It combines the entries of unchanged shreds of the previous versions of a file, with the new entries that point to the newly added changed shreds.This in whole creates a file to be served.
How it Works –
Every Document in SharePoint 2013 is now stored as multiple “shredded BLOBS” in the new “DocStreams” data table.Whenever a new Version of a document is created, a new Record is written in this data table that contains only the “Shred BLOB” of the original document that corresponds to the Change, merged with the new Changes.In other words a new Blob with Changes is added as a new row in the table.Each BLOB that gets added Contains a numerical Id that represents the source BLOB.At the end it is the job of BLOB Index to keep the track of Blobs and to create a full file with the Combination of entries that point to the unchanged shreds of the previous version(s) and the entries that point to the newly added Changed shreds.
A new property “SPWebService.FileWriteChunkSize property” has been Introduced that allows admins to Change the maximum size that will be used for each shreds. The Shred size is 64kB.
FileWriteChunkSize – FileWriteChunkSize is new in SharePoint 2013.It is a new property loosely related to FileReadChunkSize is provided to allow control of the size of a shredded BLOB. The size of shredded BLOBS can be configured by a server farm administrator in a manner similar to updating FileReadChunkSize with SharePoint 2010 using the FileWriteChunkSize property value.Configuring the FileWriteChunkSize property should be thoroughly tested in a non-production environment prior to committing any changes as a performance penalty may be incurred when too small a chunk size is configured and large file such as video files are being used frequently.