Databases Reference
In-Depth Information
Allocate
Resources
Begin
Attribute
Processing
Reading
Thread
Writing
Thread
Processing
Thread
1
2
3
Connection
Query
Response
Read Buffer
DataCache
File
Read Data
Process Data
Write Data
Read
Buffer 1
DataCache
Buffer 1
Read
Buffer 2
DataCache
Buffer 2
1
2
3
End
Processing
Release
Resources
FIGURE 21.2
To process an attribute, Analysis Services first allocates the resources, and
then starts threads for reading data, processing data, writing data.
All three threads start execution at once. However, in the beginning, only the Read Data
thread is active. Process Data and Write Data threads are blocked and are in the sleep state,
waiting for the Read Data thread to read the first chunk of data from the data source.
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