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Posted to commits@cassandra.apache.org by Apache Wiki <wi...@apache.org> on 2010/10/14 17:05:16 UTC
[Cassandra Wiki] Update of "ArchitectureCommitLog" by JingguoYao
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The "ArchitectureCommitLog" page has been changed by JingguoYao.
The comment on this change is: Disable link.
http://wiki.apache.org/cassandra/ArchitectureCommitLog?action=diff&rev1=4&rev2=5
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Each insertion (deletion) has to first write a log entry to the !CommitLog.
* The writing of all log entries is handled by a single thread in !CommitLogExecutorService.
- * For the first insert to a given !ColumnFamily CF in each !CommitLogSegment, the !CommitLogHeader is updated: the CF's dirty bit is turned on and the replay offset for CF in the !CommitLogHeader is updated with the current position (represented by a !CommitLogContext object) in the CommitLog file.
+ * For the first insert to a given !ColumnFamily CF in each !CommitLogSegment, the !CommitLogHeader is updated: the CF's dirty bit is turned on and the replay offset for CF in the !CommitLogHeader is updated with the current position (represented by a !CommitLogContext object) in the !CommitLog file.
* A !RowMutation entry is then appended to the !CommitLogSegment
* If !CommitLogSync is set to batch, the insertion further waits until the !CommitLogSegment is sync-ed to disk before the insert is allowed to proceed
* Once a !CommitLogSegment becomes too large, a new segment is created and new operations are appended there instead.