Object Storage Service:Use automatic storage tiering of OSS-HDFS to reduce storage costs

Usage notes

• If the version of JindoSDK is earlier than 6.4.0, you cannot create an object in an IA, Archive, or Cold Archive directory. If you need to create an object in an IA, Archive, or Cold Archive directory, you can create an object and save it in a Standard directory. Then, move the object to the IA, Archive, or Cold Archive directory by using the rename operation.

  If you want to directly create an object in the IA, Archive, or Cold Archive directory, you must upgrade JindoSDK to 6.4.0 or later.

• When you convert the storage class of objects to Archive or Cold Archive, additional system overheads are generated and data restoration is slow. Proceed with caution.

• You can convert the storage class of Archive objects to Cold Archive, but cannot convert the storage class of Cold Archive objects to Archive.

Billing rules

• Data retrieval fees

  You are charged data retrieval fees when you read IA, Archive, or Cold Archive objects in OSS-HDFS. We recommend that you do not store frequently accessed data as IA, Archive, or Cold Archive objects. For more information about the data retrieval fees, see Data processing fees.

• Tag fees

  When you configure a storage policy for data in OSS-HDFS, you must add tags to data blocks. You are charged for the tags based on object tagging billing rules. For more information, see Object tagging fees.

• Storage usage of objects that are stored for less than the minimum storage duration

  The minimum storage duration is 30 days for IA objects, 60 days for Archive objects, and 180 days for Cold Archive objects. To avoid unnecessary costs, make sure that objects meet the minimum storage duration requirements when you use jindofs to convert the storage class of the objects. The following table provides examples.

  Storage class conversion	Example	Calculation method of the minimum storage duration	Actual storage usage	Method to prevent storage usage of an object that is stored for less than the minimum storage duration
  Hot to cold	Conversion from Standard (stored for 10 days) to IA	OSS-HDFS does not recalculate the storage duration when the storage class of the object changes. The number of days in which the object is stored in the Standard storage class before the storage class conversion is included in the minimum storage duration of the IA object.	Storage usage of the Standard object for 10 days	Continue storing the IA object for 20 days
  	Conversion from IA (store for 10 days) to Archive		Storage usage of the IA object for 10 days	Continue storing the Archive object for 50 days
  	Conversion from Standard (store for 10 days) to Cold Archive	OSS-HDFS recalculates the storage duration when the storage class of the object changes. The number of days in which the object is stored in the Standard storage class before the storage class conversion is not included in the minimum storage duration of the Cold Archive object.	Storage usage of the Standard object for 10 days	Continue storing the Cold Archive object for 180 days
  Cold to hot	Conversion from Cold Archive (store for 10 days) to IA		Storage usage of the Cold Archive object for 10 days	Continue storing the Cold Archive object for 170 days Continue storing the IA object for 30 days after the storage class conversion

Procedure

1. Connect to an Elastic Compute Service (ECS) instance. For more information, see Connect to an instance.

2. Download the JindoFS SDK JAR package.

3. Configure the AccessKey pair and environment variables.

   1. Go to the bin directory of the installed JindoFS SDK JAR package.

      The following sample code provides an example on how to go to the bin directory of the jindofs-sdk-x.x.x-linux JAR package. If you use a different version of JindoFS SDK, replace the package name with the name of the corresponding JindoFS SDK JAR package.

      cd jindofs-sdk-x.x.x-linux/bin/

   2. Create a configuration file named jindosdk.cfg in the bin directory, and then add the following parameters to the configuration file:

      [client]
      <! -- Specify the AccessKey ID and AccessKey secret that are used to access OSS-HDFS.   -->
      fs.oss.accessKeyId = LTAI********    
      fs.oss.accessKeySecret = KZo1********
      <!-- In this example, the endpoint of the China (Hangzhou) region is used. Specify your actual endpoint.   -->
      fs.oss.endpoint = cn-hangzhou.oss-dls.aliyuncs.com                                     

   3. Configure environment variables.

      Note

      Set <JINDOSDK_CONF_DIR> to the absolute path of the jindofs.cfg configuration file.

      export JINDOSDK_CONF_DIR=<JINDOSDK_CONF_DIR>

4. Specify a storage policy for the data that is written to OSS-HDFS. The following table describes the storage policy.

   Scenario	Command	Result
   IA	./jindofs fs -setStoragePolicy -path oss://examplebucket/dir1 -policy CLOUD_IA	The objects in the dir1/ directory have a tag whose key is transition-storage-class and whose value is IA.
   Archive	./jindofs fs -setStoragePolicy -path oss://examplebucket/dir2 -policy CLOUD_AR	The objects in the dir2/ directory have a tag whose key is transition-storage-class and whose value is Archive.
   Cold Archive	./jindofs fs -setStoragePolicy -path oss://examplebucket/dir3 -policy CLOUD_COLD_AR	The objects in the dir3/ directory have a tag whose key is transition-storage-class and whose value is ColdArchive.

5. Enable the automatic storage tiering feature.

   1. Log on to the OSS console.

   2. In the left-side navigation pane, click Buckets. On the Buckets page, click the name of the bucket for which you want to enable the automatic storage tiering feature.

   3. In the left-side navigation tree, choose Data Lake > OSS-HDFS.

   4. On the OSS-HDFS tab, click Configure.

   5. In the Basic Settings section of the Automatic Storage Tiering panel, turn on Status.

      

      To prevent the automatic storage tiering feature from failing to run as expected due to incorrect configurations, OSS automatically creates a lifecycle rule to convert the storage class of objects in OSS-HDFS that have a specific tag:

      • The lifecycle rule specifies that the storage class of the objects that have a tag whose key is transition-storage-class and whose value is IA in the .dlsdata/ directory is converted to IA one day after they are last modified.

      • The lifecycle rule specifies that the storage class of the data that contains a tag whose key is transition-storage-class and whose value is Archive in the .dlsdata/ directory is changed to Archive one day after the data is last modified.

      • The lifecycle rule specifies that the storage class of the objects that have a tag whose key is transition-storage-class and whose value is ColdArchive in the .dlsdata/ directory is converted to Cold Archive one day after they are last modified.

      Important

      Do not modify the lifecycle rule that is automatically created after the automatic storage tiering feature is enabled. Otherwise, data or OSS-HDFS exceptions may occur.

   6. Click OK.

      • OSS-HDFS converts the storage class of objects based on the configured storage policy.

      • OSS loads a lifecycle rule within 24 hours after the lifecycle rule is created. After the lifecycle rule is loaded, OSS starts to execute the lifecycle rule at 08:00 (UTC+8) every day. The specific time varies based on the number of objects. The objects are converted to the specified storage class within at least 48 hours.

Related commands

./jindofs fs -setStoragePolicy -path <path> -policy <policy>

./jindofs fs -getStoragePolicy -path <path>

./jindofs fs -unsetStoragePolicy -path <path>

./jindofs fs -checkStoragePolicy -path <path>

./jindofs fs -setStoragePolicy -path <path> -policy <policy> -restoreDays <restoreDays>

FAQ

• What do I do if I accidentally delete a lifecycle rule configured for OSS-HDFS data after the automatic storage tiering feature is enabled?

• Can I convert the storage class of objects from Archive or Cold Archive to Standard or IA?

References

• Storage classes

• Storage fees