Oracle 视图 DBA_HIST_CHANNEL_WAITS 官方解释,作用,如何使用详细说明
本站中文解释
表
Oracle视图DBA_HIST_CHANNEL_WAITS是属于Oracle的性能分析视图,它显示channel操作的等待信息。所谓channel是指Oracle流传输服务(Oracle Streams)中用来收发消息的传输管道,也就是传输通道。
使用该视图可以帮助DBA检查当前系统中channel出现的等待事件。可以分析每个操作平均的等待时间、最长的等待时间等,从而找出导致等待的原因,进而寻找及解决等待事件的解决办法。
官方英文解释
DBA_HIST_CHANNEL_WAITS
display the amount of messages broadcast on KSR and KSXR channels as well as the total time taken for the broadcast to complete.
KSR channels are local to an instance, that is, only processes within an instance subscribed to the channel can receive the message. KSXR channels allow messages to be broadcast across instances. The messages broadcast and the total time to broadcast are cumulative from the start of the instance. Channels with high overall average wait times could indicate potential problems with a subscriber on that channel which can lead to poor scaled performance.
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Unique snapshot ID |
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Database ID for the snapshot |
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Instance number for the snapshot |
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The name of the KSR or KSXR channel |
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The cumulative count of messages published on the channel (from instance startup) |
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The total number of times a publisher has waited for a broadcast to complete. This metric is only pertinent for asynchronous broadcasts where the broadcast can be dispatched and publisher can wait for completion at a later point of time. A high wait count along with increased wait time can indicate a potential performance bottleneck. |
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The cumulative amount of time in microseconds that publishers have waited for message broadcast to complete. Average time for broadcast on a channel can be computed by dividing |
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The database ID of the PDB for the sampled session |
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The ID of the container that
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