title: "How Keep works"
...
-The Arvados distributed file system is called *Keep*. Keep is a content-addressable file system. This means that files are managed using special unique identifiers derived from the _contents_ of the file, rather than human-assigned file names (specifically, the MD5 hash). This has a number of advantages:
+The Arvados distributed file system is called *Keep*. Keep is a content-addressable file system. This means that files are managed using special unique identifiers derived from the _contents_ of the file (specifically, the MD5 hash), rather than human-assigned file names. This has a number of advantages:
* Files can be stored and replicated across a cluster of servers without requiring a central name server.
* Both the server and client systematically validate data integrity because the checksum is built into the identifier.
* Data duplication is minimized—two files with the same contents will have in the same identifier, and will not be stored twice.
In order to reassemble the file, Keep stores a *collection* data block which lists in sequence the data blocks that make up the original file. A collection data block may store the information for multiple files, including a directory structure.
-In this example we will use @c1bad4b39ca5a924e481008009d94e32+210@ which we added to Keep in "the first Keep tutorial":{{ site.baseurl }}/user/tutorials/tutorial-keep.html. First let us examine the contents of this collection using @arv keep get@:
+In this example we will use @c1bad4b39ca5a924e481008009d94e32+210@, which we added to Keep in "how to upload data":{{ site.baseurl }}/user/tutorials/tutorial-keep.html. First let us examine the contents of this collection using @arv keep get@:
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<pre><code>~$ <span class="userinput">arv keep get c1bad4b39ca5a924e481008009d94e32+210</span>
projects / arvados.git / blobdiff