HDFS-9042. Update document for the Storage policy name (Contributed by J.Andreina)

(cherry picked from commit d8455479b8)
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Vinayakumar B 2015-09-12 12:36:12 +05:30
parent f2cc6b5fdf
commit 7d3e882a49
2 changed files with 5 additions and 2 deletions

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@ -44,6 +44,9 @@ Release 2.7.2 - UNRELEASED
HDFS-9033. dfsadmin -metasave prints "NaN" for cache used%.
(Brahma Reddy Battula via aajisaka)
HDFS-9042. Update document for the Storage policy name
(J.Andreina via vinayakumarb)
Release 2.7.1 - 2015-07-06
INCOMPATIBLE CHANGES

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@ -73,14 +73,14 @@ The following is a typical storage policy table.
| **Policy** **ID** | **Policy** **Name** | **Block Placement** **(n  replicas)** | **Fallback storages** **for creation** | **Fallback storages** **for replication** |
|:---- |:---- |:---- |:---- |:---- |
| 15 | Lasy\_Persist | RAM\_DISK: 1, DISK: *n*-1 | DISK | DISK |
| 15 | Lazy\_Persist | RAM\_DISK: 1, DISK: *n*-1 | DISK | DISK |
| 12 | All\_SSD | SSD: *n* | DISK | DISK |
| 10 | One\_SSD | SSD: 1, DISK: *n*-1 | SSD, DISK | SSD, DISK |
| 7 | Hot (default) | DISK: *n* | \<none\> | ARCHIVE |
| 5 | Warm | DISK: 1, ARCHIVE: *n*-1 | ARCHIVE, DISK | ARCHIVE, DISK |
| 2 | Cold | ARCHIVE: *n* | \<none\> | \<none\> |
Note that the Lasy\_Persist policy is useful only for single replica blocks. For blocks with more than one replicas, all the replicas will be written to DISK since writing only one of the replicas to RAM\_DISK does not improve the overall performance.
Note that the Lazy\_Persist policy is useful only for single replica blocks. For blocks with more than one replicas, all the replicas will be written to DISK since writing only one of the replicas to RAM\_DISK does not improve the overall performance.
### Storage Policy Resolution