[jira] [Commented] (HDFS-5182) BlockReaderLocal must allow zero-copy reads only when the DN believes it's valid

2014-02-05 Thread Haohui Mai (JIRA)
[ https://issues.apache.org/jira/browse/HDFS-5182?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=13892684#comment-13892684 ] Haohui Mai commented on HDFS-5182: -- Thanks very much for the clarification. > BlockReader

[jira] [Commented] (HDFS-5182) BlockReaderLocal must allow zero-copy reads only when the DN believes it's valid

2014-02-05 Thread Todd Lipcon (JIRA)
[ https://issues.apache.org/jira/browse/HDFS-5182?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=13892476#comment-13892476 ] Todd Lipcon commented on HDFS-5182: --- I think you guys are talking past each other here.

[jira] [Commented] (HDFS-5182) BlockReaderLocal must allow zero-copy reads only when the DN believes it's valid

2014-02-04 Thread Colin Patrick McCabe (JIRA)
[ https://issues.apache.org/jira/browse/HDFS-5182?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=13891547#comment-13891547 ] Colin Patrick McCabe commented on HDFS-5182: bq. Okay now it looks more clear t

[jira] [Commented] (HDFS-5182) BlockReaderLocal must allow zero-copy reads only when the DN believes it's valid

2014-02-04 Thread Haohui Mai (JIRA)
[ https://issues.apache.org/jira/browse/HDFS-5182?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=13891536#comment-13891536 ] Haohui Mai commented on HDFS-5182: -- Okay now it looks more clear to me now. Thanks for the

[jira] [Commented] (HDFS-5182) BlockReaderLocal must allow zero-copy reads only when the DN believes it's valid

2014-02-04 Thread Colin Patrick McCabe (JIRA)
[ https://issues.apache.org/jira/browse/HDFS-5182?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=13891500#comment-13891500 ] Colin Patrick McCabe commented on HDFS-5182: bq. I should have said it more con

[jira] [Commented] (HDFS-5182) BlockReaderLocal must allow zero-copy reads only when the DN believes it's valid

2014-02-04 Thread Haohui Mai (JIRA)
[ https://issues.apache.org/jira/browse/HDFS-5182?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=13891378#comment-13891378 ] Haohui Mai commented on HDFS-5182: -- I should have said it more concretely. What I'm propos

[jira] [Commented] (HDFS-5182) BlockReaderLocal must allow zero-copy reads only when the DN believes it's valid

2014-02-04 Thread Colin Patrick McCabe (JIRA)
[ https://issues.apache.org/jira/browse/HDFS-5182?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=13891350#comment-13891350 ] Colin Patrick McCabe commented on HDFS-5182: [~wheat9]: the shared memory segme

[jira] [Commented] (HDFS-5182) BlockReaderLocal must allow zero-copy reads only when the DN believes it's valid

2014-02-04 Thread Haohui Mai (JIRA)
[ https://issues.apache.org/jira/browse/HDFS-5182?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=13891257#comment-13891257 ] Haohui Mai commented on HDFS-5182: -- I'm curious why shared memory segment is necessary --

[jira] [Commented] (HDFS-5182) BlockReaderLocal must allow zero-copy reads only when the DN believes it's valid

2014-02-04 Thread Colin Patrick McCabe (JIRA)
[ https://issues.apache.org/jira/browse/HDFS-5182?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=13891238#comment-13891238 ] Colin Patrick McCabe commented on HDFS-5182: [~wheat9]: I think you're mixing u

[jira] [Commented] (HDFS-5182) BlockReaderLocal must allow zero-copy reads only when the DN believes it's valid

2014-02-04 Thread Haohui Mai (JIRA)
[ https://issues.apache.org/jira/browse/HDFS-5182?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=13891042#comment-13891042 ] Haohui Mai commented on HDFS-5182: -- It looks like to me that passing the file descriptor i

[jira] [Commented] (HDFS-5182) BlockReaderLocal must allow zero-copy reads only when the DN believes it's valid

2014-01-09 Thread Todd Lipcon (JIRA)
[ https://issues.apache.org/jira/browse/HDFS-5182?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=13867175#comment-13867175 ] Todd Lipcon commented on HDFS-5182: --- bq. What I was referring to here is where a client h

[jira] [Commented] (HDFS-5182) BlockReaderLocal must allow zero-copy reads only when the DN believes it's valid

2014-01-09 Thread Colin Patrick McCabe (JIRA)
[ https://issues.apache.org/jira/browse/HDFS-5182?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=13867110#comment-13867110 ] Colin Patrick McCabe commented on HDFS-5182: bq. That seems much longer than ne

[jira] [Commented] (HDFS-5182) BlockReaderLocal must allow zero-copy reads only when the DN believes it's valid

2014-01-09 Thread Todd Lipcon (JIRA)
[ https://issues.apache.org/jira/browse/HDFS-5182?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=13867073#comment-13867073 ] Todd Lipcon commented on HDFS-5182: --- bq. it will check to see if the segment is anchorabl

[jira] [Commented] (HDFS-5182) BlockReaderLocal must allow zero-copy reads only when the DN believes it's valid

2014-01-09 Thread Colin Patrick McCabe (JIRA)
[ https://issues.apache.org/jira/browse/HDFS-5182?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=13866545#comment-13866545 ] Colin Patrick McCabe commented on HDFS-5182: A few notes about the planned impl

[jira] [Commented] (HDFS-5182) BlockReaderLocal must allow zero-copy reads only when the DN believes it's valid

2013-12-06 Thread Colin Patrick McCabe (JIRA)
[ https://issues.apache.org/jira/browse/HDFS-5182?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=13841882#comment-13841882 ] Colin Patrick McCabe commented on HDFS-5182: The data xceiver protocol would st

[jira] [Commented] (HDFS-5182) BlockReaderLocal must allow zero-copy reads only when the DN believes it's valid

2013-12-06 Thread Todd Lipcon (JIRA)
[ https://issues.apache.org/jira/browse/HDFS-5182?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=13841685#comment-13841685 ] Todd Lipcon commented on HDFS-5182: --- bq. It's edge-triggered in the sense that both the D

[jira] [Commented] (HDFS-5182) BlockReaderLocal must allow zero-copy reads only when the DN believes it's valid

2013-12-03 Thread Colin Patrick McCabe (JIRA)
[ https://issues.apache.org/jira/browse/HDFS-5182?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=13838283#comment-13838283 ] Colin Patrick McCabe commented on HDFS-5182: bq. Can you explain further what y

[jira] [Commented] (HDFS-5182) BlockReaderLocal must allow zero-copy reads only when the DN believes it's valid

2013-12-03 Thread Todd Lipcon (JIRA)
[ https://issues.apache.org/jira/browse/HDFS-5182?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=13838215#comment-13838215 ] Todd Lipcon commented on HDFS-5182: --- {quote} The other way (let's call this choice #2) is

[jira] [Commented] (HDFS-5182) BlockReaderLocal must allow zero-copy reads only when the DN believes it's valid

2013-12-03 Thread Colin Patrick McCabe (JIRA)
[ https://issues.apache.org/jira/browse/HDFS-5182?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=13838159#comment-13838159 ] Colin Patrick McCabe commented on HDFS-5182: So, previously we discussed a few