Batch 11.7 Partitioned Chunk Processing

gistfile1.txt

1.
 <Create StepContext>
2.
 <Store step level properties in StepContext>
3.
 <->[StepListener.beforeStep...] // thread A
4.
 <->[PartitionReducer.beginPartitionedStep] // thread A
5.
 <->[PartitionMapper.mapPartitions] // thread A
// per partition - on thread Px:
a. [<begin transaction> ]
b. <->ItemReader.open // thread Px
c. <->ItemWriter.open // thread Px
d. [<commit transaction> ]
a. <repeat until no more items> {
i. <begin checkpoint [<begin transaction> ]>
ii. <repeat until commit criteria reached> {
1. <->ItemReader.readItem // thread Px
2. <->ItemProcessor.processItem // thread Px
3. <add item to buffer>
iii. }
iv. <->ItemWriter.writeItems // thread Px
v. <->[ItemReader.checkpointInfo] // thread Px
vi. <->[ItemWriter.checkpointInfo] // thread Px
vii. <Store (partition-local) StepContext persistent area>
viii. <commit checkpoint (commit transaction)>
ix. <->[PartitionCollector.collectPartitionData] // thread Px
e. }
f. [<begin transaction> ]
g. <->ItemWriter.close // thread Px
h. <->ItemReader.close // thread Px
i. [<commit transaction> ]
j. <->[PartitionCollector.collectPartitionData] // thread Px
6.
 [<begin transaction> ] // thread A
7.
 // Actions 9-12 run continuously until all partitions end.
8.
 // when collector payload arrives:
9.
 <->[PartitionAnalyzer.analyzeCollectorData] // thread A
10.
 // when partition ends:
11.
 <->[PartitionAnalyzer.analyzeStatus] // thread A
12.
 // Remaining actions run after all partitions end:
13.
 // if rollback condition occurs:
14.
 <->[PartitionReducer.rollbackPartitionedStep] // thread A
15.
 [<rollback transaction >]
16.
 // else not rollback
17.
 <->[PartitionReducer.beforePartitionedStepCompletion] // thread A
18.
 [<commit transaction> ] // thread A
19.
 <->[PartitionReducer.afterPartitionedStepCompletion] // thread A
20.
 <->[StepListener.afterStep...] // thread A
21.
 <Store StepContext persistent area>
22.
 <Destroy StepContext>