vine: imbalanced temp file replication

[JinZhou5042]

In the following run I intended to set a large number of temp file replications. Although I didn’t encounter any issues like tasks being forsaken or slowdowns in the end, the imbalance in temp file replications concerns me a bit.

If the workflow runs long enough, every file will eventually reach its expected replication count. But within a specific time period, some files get replicated really well, while others are under-replicated, which could increase the risk of submitting recovery tasks.

The x-axis represents numerical file index while the y-axis represents the number of replicas for each file. File pruning was disabled.

[JinZhou5042]

solved with #4076, this was because some source workers holding a specific replica just cannot transfer more...