[
https://issues.apache.org/jira/browse/HDFS-8203?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=14529735#comment-14529735
]
Yi Liu edited comment on HDFS-8203 at 5/6/15 1:47 AM:
------------------------------------------------------
Update the patch.
Currently we have the {{curStripedBuf}}, so {{seek}} could be simpler. I
update the logic of {{readOneStripe}}.
In {{readOneStripe}}, we try to read striped group cells to fill the buffer.
But if seek happens, the target pos can be at the middle of striped group cells:
# We don't need to fetch all striped group cells, just need to start from the
cell contains the target pos.
The tests passed in my local env.
was (Author: hitliuyi):
Update the patch.
Current we have the {{curStripedBuf}}, so {{seek}} could be simpler. I update
the logic of {{readOneStripe}}.
In {{readOneStripe}}, we try to read striped group cells to fill the buffer.
But if seek happens, the target pos can be at the middle of striped group cells:
# We don't need to fetch all striped group cells, just need to start from the
cell contains the target pos.
The tests passed in my local env.
> Erasure Coding: Seek and other Ops in DFSStripedInputStream.
> ------------------------------------------------------------
>
> Key: HDFS-8203
> URL: https://issues.apache.org/jira/browse/HDFS-8203
> Project: Hadoop HDFS
> Issue Type: Sub-task
> Reporter: Yi Liu
> Assignee: Yi Liu
> Attachments: HDFS-8203.001.patch, HDFS-8203.002.patch
>
>
> In HDFS-7782 and HDFS-8033, we handle pread and stateful read for
> {{DFSStripedInputStream}}, we also need handle other operations, such as
> {{seek}}, zerocopy read ...
--
This message was sent by Atlassian JIRA
(v6.3.4#6332)
