[jira] [Commented] (HDFS-5682) Heterogeneous Storage phase 2 - APIs to expose Storage Types
[
https://issues.apache.org/jira/browse/HDFS-5682?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=14384471#comment-14384471
]
Arpit Agarwal commented on HDFS-5682:
-
Most of the remaining work planned for this Jira has been completed under
HDFS-6584 and HDFS-7584. There is also some overlap with HDFS-6581. I plan to
resolve this Jira as obsolete soon.
{quote}
Before you start trying to define multiple types of storage, you need to first
consider the data flow in and out and what sort of processes occur on the
storage and then for each type of storage, how you would implement it.
As an example... What happens to the data when there's an insert, compaction,
major compaction, indexing (secondary) , etc ... and for each of these
categories how the new storage unit will function.
{quote}
Hi [~msegel], none of these are filesystem primitives. HDFS just makes raw
storage types available for use. The kind of analysis you describe is relevant
to components higher up in the stack.
> Heterogeneous Storage phase 2 - APIs to expose Storage Types
>
>
> Key: HDFS-5682
> URL: https://issues.apache.org/jira/browse/HDFS-5682
> Project: Hadoop HDFS
> Issue Type: New Feature
> Components: datanode, namenode
>Reporter: Arpit Agarwal
>Assignee: Arpit Agarwal
> Attachments: 20140522-Heterogeneous-Storages-API.pdf
>
>
> Phase 1 (HDFS-2832) added support to present the DataNode as a collection of
> discrete storages of different types.
> This Jira is to track phase 2 of the Heterogeneous Storage work which
> involves exposing Storage Types to applications and adding Quota Management
> support for administrators.
> This phase will also include tools support for administrators/users.
--
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[jira] [Commented] (HDFS-5682) Heterogeneous Storage phase 2 - APIs to expose Storage Types
[ https://issues.apache.org/jira/browse/HDFS-5682?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=14383717#comment-14383717 ] Michael Segel commented on HDFS-5682: -- You really can't start looking at this issue until you understand how it will impact things like scanning. Before you start trying to define multiple types of storage, you need to first consider the data flow in and out and what sort of processes occur on the storage and then for each type of storage, how you would implement it. As an example... What happens to the data when there's an insert, compaction, major compaction, indexing (secondary) , etc ... and for each of these categories how the new storage unit will function. Looking at the spec, (pdf) this thought process seems to be missing. > Heterogeneous Storage phase 2 - APIs to expose Storage Types > > > Key: HDFS-5682 > URL: https://issues.apache.org/jira/browse/HDFS-5682 > Project: Hadoop HDFS > Issue Type: New Feature > Components: datanode, namenode >Reporter: Arpit Agarwal >Assignee: Arpit Agarwal > Attachments: 20140522-Heterogeneous-Storages-API.pdf > > > Phase 1 (HDFS-2832) added support to present the DataNode as a collection of > discrete storages of different types. > This Jira is to track phase 2 of the Heterogeneous Storage work which > involves exposing Storage Types to applications and adding Quota Management > support for administrators. > This phase will also include tools support for administrators/users. -- This message was sent by Atlassian JIRA (v6.3.4#6332)
[jira] [Commented] (HDFS-5682) Heterogeneous Storage phase 2 - APIs to expose Storage Types
[ https://issues.apache.org/jira/browse/HDFS-5682?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=14071358#comment-14071358 ] Vinayakumar B commented on HDFS-5682: - Hi [~neetagarimella], Most part of this feature is being implemented as part of HDFS-6584 ( Archival Storage Support ). You can take a look at it. Thanks > Heterogeneous Storage phase 2 - APIs to expose Storage Types > > > Key: HDFS-5682 > URL: https://issues.apache.org/jira/browse/HDFS-5682 > Project: Hadoop HDFS > Issue Type: New Feature > Components: datanode, namenode >Reporter: Arpit Agarwal >Assignee: Arpit Agarwal > Attachments: 20140522-Heterogeneous-Storages-API.pdf > > > Phase 1 (HDFS-2832) added support to present the DataNode as a collection of > discrete storages of different types. > This Jira is to track phase 2 of the Heterogeneous Storage work which > involves exposing Storage Types to applications and adding Quota Management > support for administrators. > This phase will also include tools support for administrators/users. -- This message was sent by Atlassian JIRA (v6.2#6252)
[jira] [Commented] (HDFS-5682) Heterogeneous Storage phase 2 - APIs to expose Storage Types
[ https://issues.apache.org/jira/browse/HDFS-5682?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=14034729#comment-14034729 ] Neeta Garimella commented on HDFS-5682: --- Hi, I'm trying to determine when this feature will be released. Hadoop roadmap wiki http://wiki.apache.org/hadoop/Roadmap lists this feature under 2.5, though the affected release in the header (at the top) is listed as 3.0. Could you clarify which release will this be delivered and tentative time-frame 4Q14, or 2015 to help us align our product roadmap. Thanks much for your response. > Heterogeneous Storage phase 2 - APIs to expose Storage Types > > > Key: HDFS-5682 > URL: https://issues.apache.org/jira/browse/HDFS-5682 > Project: Hadoop HDFS > Issue Type: Bug >Affects Versions: 3.0.0 >Reporter: Arpit Agarwal >Assignee: Arpit Agarwal > Attachments: 20140522-Heterogeneous-Storages-API.pdf > > > Phase 1 (HDFS-2832) added support to present the DataNode as a collection of > discrete storages of different types. > This Jira is to track phase 2 of the Heterogeneous Storage work which > involves exposing Storage Types to applications and adding Quota Management > support for administrators. > This phase will also include tools support for administrators/users. -- This message was sent by Atlassian JIRA (v6.2#6252)
[jira] [Commented] (HDFS-5682) Heterogeneous Storage phase 2 - APIs to expose Storage Types
[ https://issues.apache.org/jira/browse/HDFS-5682?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=14010512#comment-14010512 ] Zesheng Wu commented on HDFS-5682: -- Thanks for the responses [~arpitagarwal] bq.The function name should communicate that this is disk space quota for a specific storage type, as opposed to the overall quotas which are set with setQuota. If the proposed name is hard to follow, how about get/setsetQuotaByStorageType? Yes, get/setQuotaByStorageType will be clearer. bq.Let's defer this for now. The API and protocol can both be easily extended in a backwards compatible manner in the future without affecting existing applications. OK bq. We have to differentiate between quota unavailability vs disk space availability. The former will result in a quota violation exception, the latter will result in the behavior you described. We discuss the reasons for this in the HDFS-2832 design doc. Got it, thanks. I will look into the HDFS-2832 doc for more details. > Heterogeneous Storage phase 2 - APIs to expose Storage Types > > > Key: HDFS-5682 > URL: https://issues.apache.org/jira/browse/HDFS-5682 > Project: Hadoop HDFS > Issue Type: Bug >Affects Versions: 3.0.0 >Reporter: Arpit Agarwal >Assignee: Arpit Agarwal > Attachments: 20140522-Heterogeneous-Storages-API.pdf > > > Phase 1 (HDFS-2832) added support to present the DataNode as a collection of > discrete storages of different types. > This Jira is to track phase 2 of the Heterogeneous Storage work which > involves exposing Storage Types to applications and adding Quota Management > support for administrators. > This phase will also include tools support for administrators/users. -- This message was sent by Atlassian JIRA (v6.2#6252)
[jira] [Commented] (HDFS-5682) Heterogeneous Storage phase 2 - APIs to expose Storage Types
[
https://issues.apache.org/jira/browse/HDFS-5682?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=14010157#comment-14010157
]
Arpit Agarwal commented on HDFS-5682:
-
Thanks for the feedback [~wuzesheng]. My responses are below.
bq. 1. About the storage type, because I didn't participate the discussion in
HDFS-2832, I am confused by the current storage type DISK and SSD. I think SSD
is also one type of disk, DISK and SSD are not orthogonal. Can we change
storage type to HDD and SDD, this will be more straightforward?
Good point, I'll look into making the names clearer. In a subsequent revision
of the API we would like to eliminate the hard-coded names from code altogether.
bq. 2. About setStorageTypeSpaceQuota/getStorageTypeSpaceQuota, these two
names are not very natural. From the literal meaning, it sounds like
setting/getting space quota on some storage type other than some type of
storage. I would suggest that setStorageSpaceQuota/getStorageSpaceQuota will be
better. I am not a native English speaker, if I were wrong, just ignore this.
The function name should communicate that this is disk space quota for a
specific storage type, as opposed to the overall quotas which are set with
{{setQuota}}. If the proposed name is hard to follow, how about
{{get}}/{{setsetQuotaByStorageType}}?
bq. 3. About the command line, hdfs dfsadmin -get(set)StorageTypeSpaceQuota, I
think get(set) one storage type once is simple and straightforward, if we
get(set) more than one once, because there's no atomicity guarantee, it's
complicated to handle failure.
Yes I think we can simplify the command line as you suggested.
bq. 4. About the StoragePreference class, as you said in the design doc in
HDFS-2832, in the future HDFS will support place replicas on different
storages, such as 1 on SSD, and 2 on HDD. I would suggest that
StoragePerference class can support specifying storage type of each replica
now, in this way, we can easily support the above feature in the future.
Let's defer this for now. The API and protocol can both be easily extended in a
backwards compatible manner in the future without affecting existing
applications.
bq. 5. About the create file sematics, as you said in the doc "During file
creation there must be sufficient quota to place at least one block times the
replication factor on the target storage type, otherwise the request is falied
immediately with QuotaExceededException", I think it will be more natural and
friendly that first create the file on the default storage(HDD) if there's not
enough space of desired storage type , and than let the namenode replicate the
block to desired storage lazily when there's enough space available.
We have to differentiate between quota unavailability vs disk space
availability. The former will result in a quota violation exception, the latter
will result in the behavior you described. We discuss the reasons for this in
the HDFS-2832 design doc.
> Heterogeneous Storage phase 2 - APIs to expose Storage Types
>
>
> Key: HDFS-5682
> URL: https://issues.apache.org/jira/browse/HDFS-5682
> Project: Hadoop HDFS
> Issue Type: Bug
>Affects Versions: 3.0.0
>Reporter: Arpit Agarwal
>Assignee: Arpit Agarwal
> Attachments: 20140522-Heterogeneous-Storages-API.pdf
>
>
> Phase 1 (HDFS-2832) added support to present the DataNode as a collection of
> discrete storages of different types.
> This Jira is to track phase 2 of the Heterogeneous Storage work which
> involves exposing Storage Types to applications and adding Quota Management
> support for administrators.
> This phase will also include tools support for administrators/users.
--
This message was sent by Atlassian JIRA
(v6.2#6252)
[jira] [Commented] (HDFS-5682) Heterogeneous Storage phase 2 - APIs to expose Storage Types
[ https://issues.apache.org/jira/browse/HDFS-5682?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=14008153#comment-14008153 ] Zesheng Wu commented on HDFS-5682: -- I read through the API doc, its really very clear:) Following are some minor suggestions: 1. About the storage type, because I didn't participate the discussion in HDFS-2832, I am confused by the current storage type DISK and SSD. I think SSD is also one type of disk, DISK and SSD are not orthogonal. Can we change storage type to HDD and SDD, this will be more straightforward? 2. About setStorageTypeSpaceQuota/getStorageTypeSpaceQuota, these two names are not very natural. From the literal meaning, it sounds like setting/getting space quota on some storage type other than some type of storage. I would suggest that setStorageSpaceQuota/getStorageSpaceQuota will be better. I am not a native English speaker, if I were wrong, just ignore this. 3. About the command line, hdfs dfsadmin -get(set)StorageTypeSpaceQuota, I think get(set) one storage type once is simple and straightforward, if we get(set) more than one once, because there's no atomicity guarantee, it's complicated to handle failure. 4. About the StoragePreference class, as you said in the design doc in HDFS-2832, in the future HDFS will support place replicas on different storages, such as 1 on SSD, and 2 on HDD. I would suggest that StoragePerference class can support specifying storage type of each replica now, in this way, we can easily support the above feature in the future. 5. About the create file sematics, as you said in the doc "During file creation there must be sufficient quota to place at least one block times the replication factor on the target storage type, otherwise the request is falied immediately with QuotaExceededException", I think it will be more natural and friendly that first create the file on the default storage(HDD) if there's not enough space of desired storage type , and than let the namenode replicate the block to desired storage lazily when there's enough space available. > Heterogeneous Storage phase 2 - APIs to expose Storage Types > > > Key: HDFS-5682 > URL: https://issues.apache.org/jira/browse/HDFS-5682 > Project: Hadoop HDFS > Issue Type: Bug >Affects Versions: 3.0.0 >Reporter: Arpit Agarwal >Assignee: Arpit Agarwal > Attachments: 20140522-Heterogeneous-Storages-API.pdf > > > Phase 1 (HDFS-2832) added support to present the DataNode as a collection of > discrete storages of different types. > This Jira is to track phase 2 of the Heterogeneous Storage work which > involves exposing Storage Types to applications and adding Quota Management > support for administrators. > This phase will also include tools support for administrators/users. -- This message was sent by Atlassian JIRA (v6.2#6252)
[jira] [Commented] (HDFS-5682) Heterogeneous Storage phase 2 - APIs to expose Storage Types
[ https://issues.apache.org/jira/browse/HDFS-5682?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=14006702#comment-14006702 ] Zesheng Wu commented on HDFS-5682: -- Thanks [~arpitagarwal], I will take a look at the API doc and give my feedback soon. > Heterogeneous Storage phase 2 - APIs to expose Storage Types > > > Key: HDFS-5682 > URL: https://issues.apache.org/jira/browse/HDFS-5682 > Project: Hadoop HDFS > Issue Type: Bug >Affects Versions: 3.0.0 >Reporter: Arpit Agarwal >Assignee: Arpit Agarwal > Attachments: 20140522-Heterogeneous-Storages-API.pdf > > > Phase 1 (HDFS-2832) added support to present the DataNode as a collection of > discrete storages of different types. > This Jira is to track phase 2 of the Heterogeneous Storage work which > involves exposing Storage Types to applications and adding Quota Management > support for administrators. > This phase will also include tools support for administrators/users. -- This message was sent by Atlassian JIRA (v6.2#6252)
[jira] [Commented] (HDFS-5682) Heterogeneous Storage phase 2 - APIs to expose Storage Types
[ https://issues.apache.org/jira/browse/HDFS-5682?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=13998940#comment-13998940 ] Nick Dimiduk commented on HDFS-5682: Have you considered making use of the SSD via BucketCache? I did some [experiments|http://www.n10k.com/blog/blockcache-showdown/] with it a while back, to great success. Let's take this conversation to user@hbase if you'd like to discuss further. > Heterogeneous Storage phase 2 - APIs to expose Storage Types > > > Key: HDFS-5682 > URL: https://issues.apache.org/jira/browse/HDFS-5682 > Project: Hadoop HDFS > Issue Type: Bug >Affects Versions: 3.0.0 >Reporter: Arpit Agarwal >Assignee: Arpit Agarwal > > Phase 1 (HDFS-2832) added support to present the DataNode as a collection of > discrete storages of different types. > This Jira is to track phase 2 of the Heterogeneous Storage work which > involves exposing Storage Types to applications and adding Quota Management > support for administrators. > This phase will also include tools support for administrators/users. -- This message was sent by Atlassian JIRA (v6.2#6252)
[jira] [Commented] (HDFS-5682) Heterogeneous Storage phase 2 - APIs to expose Storage Types
[ https://issues.apache.org/jira/browse/HDFS-5682?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=13998277#comment-13998277 ] Arpit Agarwal commented on HDFS-5682: - bq. Last week I looked into HDFS-2832 and found that we need HDFS-5682 to be finished before heterogeneous storage can be used, so I asked for the progress of this issue. As you said this was deprioritized, I am wondering whether you can give a more specific plan, and I can spend some time working on some of the subtasks. Now that 2.4 is finished we'll have an API doc out soon. > Heterogeneous Storage phase 2 - APIs to expose Storage Types > > > Key: HDFS-5682 > URL: https://issues.apache.org/jira/browse/HDFS-5682 > Project: Hadoop HDFS > Issue Type: Bug >Affects Versions: 3.0.0 >Reporter: Arpit Agarwal >Assignee: Arpit Agarwal > > Phase 1 (HDFS-2832) added support to present the DataNode as a collection of > discrete storages of different types. > This Jira is to track phase 2 of the Heterogeneous Storage work which > involves exposing Storage Types to applications and adding Quota Management > support for administrators. > This phase will also include tools support for administrators/users. -- This message was sent by Atlassian JIRA (v6.2#6252)
[jira] [Commented] (HDFS-5682) Heterogeneous Storage phase 2 - APIs to expose Storage Types
[ https://issues.apache.org/jira/browse/HDFS-5682?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=13998366#comment-13998366 ] Zesheng Wu commented on HDFS-5682: -- Thanks [~arpitagarwal] Looking forward to read the API doc soon:) > Heterogeneous Storage phase 2 - APIs to expose Storage Types > > > Key: HDFS-5682 > URL: https://issues.apache.org/jira/browse/HDFS-5682 > Project: Hadoop HDFS > Issue Type: Bug >Affects Versions: 3.0.0 >Reporter: Arpit Agarwal >Assignee: Arpit Agarwal > > Phase 1 (HDFS-2832) added support to present the DataNode as a collection of > discrete storages of different types. > This Jira is to track phase 2 of the Heterogeneous Storage work which > involves exposing Storage Types to applications and adding Quota Management > support for administrators. > This phase will also include tools support for administrators/users. -- This message was sent by Atlassian JIRA (v6.2#6252)
[jira] [Commented] (HDFS-5682) Heterogeneous Storage phase 2 - APIs to expose Storage Types
[ https://issues.apache.org/jira/browse/HDFS-5682?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=13996072#comment-13996072 ] Zesheng Wu commented on HDFS-5682: -- Thanks [~ndimiduk], here are some details of our SLA requirements: The background is that we have a structured data storage system which is very similar with amazon DynamoDB and is built on HBase. This system is intended to serve multi-tenants, in order to ensure the SLA, such as 99% read/write latency, we need to place the data on SSD. One straightforward way is to set up a hdfs cluster with all SSD data disks, but this is cost too much. So we need to reduce the cost. Another way is to set up a hdfs cluster with both SSD and HDD data disks, we can put 1 replica on SSD, and the other 2 on HDD. This is really a typical scenario of hdfs heterogeneous storage. > Heterogeneous Storage phase 2 - APIs to expose Storage Types > > > Key: HDFS-5682 > URL: https://issues.apache.org/jira/browse/HDFS-5682 > Project: Hadoop HDFS > Issue Type: Bug >Affects Versions: 3.0.0 >Reporter: Arpit Agarwal >Assignee: Arpit Agarwal > > Phase 1 (HDFS-2832) added support to present the DataNode as a collection of > discrete storages of different types. > This Jira is to track phase 2 of the Heterogeneous Storage work which > involves exposing Storage Types to applications and adding Quota Management > support for administrators. > This phase will also include tools support for administrators/users. -- This message was sent by Atlassian JIRA (v6.2#6252)
[jira] [Commented] (HDFS-5682) Heterogeneous Storage phase 2 - APIs to expose Storage Types
[ https://issues.apache.org/jira/browse/HDFS-5682?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=13995299#comment-13995299 ] Arpit Agarwal commented on HDFS-5682: - Hi [~wuzesheng], this was deprioritized due to 2.4 stabilization. We will post a document describing the proposed API within the next couple of weeks, followed shortly by the detailed design doc. > Heterogeneous Storage phase 2 - APIs to expose Storage Types > > > Key: HDFS-5682 > URL: https://issues.apache.org/jira/browse/HDFS-5682 > Project: Hadoop HDFS > Issue Type: Bug >Affects Versions: 3.0.0 >Reporter: Arpit Agarwal >Assignee: Arpit Agarwal > > Phase 1 (HDFS-2832) added support to present the DataNode as a collection of > discrete storages of different types. > This Jira is to track phase 2 of the Heterogeneous Storage work which > involves exposing Storage Types to applications and adding Quota Management > support for administrators. > This phase will also include tools support for administrators/users. -- This message was sent by Atlassian JIRA (v6.2#6252)
[jira] [Commented] (HDFS-5682) Heterogeneous Storage phase 2 - APIs to expose Storage Types
[ https://issues.apache.org/jira/browse/HDFS-5682?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=13996033#comment-13996033 ] Nick Dimiduk commented on HDFS-5682: Hi [~wuzesheng]. Can you describe your SLA requirements in detail? Maybe these needs can be addressed in other ways? > Heterogeneous Storage phase 2 - APIs to expose Storage Types > > > Key: HDFS-5682 > URL: https://issues.apache.org/jira/browse/HDFS-5682 > Project: Hadoop HDFS > Issue Type: Bug >Affects Versions: 3.0.0 >Reporter: Arpit Agarwal >Assignee: Arpit Agarwal > > Phase 1 (HDFS-2832) added support to present the DataNode as a collection of > discrete storages of different types. > This Jira is to track phase 2 of the Heterogeneous Storage work which > involves exposing Storage Types to applications and adding Quota Management > support for administrators. > This phase will also include tools support for administrators/users. -- This message was sent by Atlassian JIRA (v6.2#6252)
[jira] [Commented] (HDFS-5682) Heterogeneous Storage phase 2 - APIs to expose Storage Types
[ https://issues.apache.org/jira/browse/HDFS-5682?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=13995944#comment-13995944 ] Zesheng Wu commented on HDFS-5682: -- Thanks [~arpitagarwal], recently some of the our users have strong requirement of read/write SLA on HBase, and we notice that HDFS's heterogeneous storage feature is really interesting and helpful, thanks for your valuable work on this:) Last week I looked into HDFS-2832 and found that we need HDFS-5682 to be finished before heterogeneous storage can be used, so I asked for the progress of this issue. As you said this was deprioritized, I am wondering whether you can give a more specific plan, and I can spend some time working on some of the subtasks. > Heterogeneous Storage phase 2 - APIs to expose Storage Types > > > Key: HDFS-5682 > URL: https://issues.apache.org/jira/browse/HDFS-5682 > Project: Hadoop HDFS > Issue Type: Bug >Affects Versions: 3.0.0 >Reporter: Arpit Agarwal >Assignee: Arpit Agarwal > > Phase 1 (HDFS-2832) added support to present the DataNode as a collection of > discrete storages of different types. > This Jira is to track phase 2 of the Heterogeneous Storage work which > involves exposing Storage Types to applications and adding Quota Management > support for administrators. > This phase will also include tools support for administrators/users. -- This message was sent by Atlassian JIRA (v6.2#6252)
[jira] [Commented] (HDFS-5682) Heterogeneous Storage phase 2 - APIs to expose Storage Types
[ https://issues.apache.org/jira/browse/HDFS-5682?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=13994405#comment-13994405 ] Zesheng Wu commented on HDFS-5682: -- Hi [~arpitagarwal] how is this issue going? When will you plan to release an usable version of HSM ? > Heterogeneous Storage phase 2 - APIs to expose Storage Types > > > Key: HDFS-5682 > URL: https://issues.apache.org/jira/browse/HDFS-5682 > Project: Hadoop HDFS > Issue Type: Bug >Affects Versions: 3.0.0 >Reporter: Arpit Agarwal >Assignee: Arpit Agarwal > > Phase 1 (HDFS-2832) added support to present the DataNode as a collection of > discrete storages of different types. > This Jira is to track phase 2 of the Heterogeneous Storage work which > involves exposing Storage Types to applications and adding Quota Management > support for administrators. > This phase will also include tools support for administrators/users. -- This message was sent by Atlassian JIRA (v6.2#6252)
