storage deal related problems

[leviok]

I personally think that the main task of the current network should be to increase effective storage. Let me talk about the current problems I have encountered.

1. Some people still have a big misunderstanding about the usability of network. They believe that the data stored on the network needs to wait for the seal to complete before it is available. In fact, the data on the miner side can be retrieved after the unseal file is generated in current lotus implementation. This needs to clarify to everyone, especially slingshorters.
2. As i mentioned in [ feature request ] make fast-retrieval really fast! (UX related) #3791, retrieval can be faster and more usable. Let me try to explain more clearly. In the current lotus implementation, the tmp file will be generated after the piece data is uploaded to the miner side, and the unseal file generated by the packing will be generated by them, and will be deleted after the seal completed. So users can retrieve the piece immediately after uploading the piece, obtain the data through the tmp file. After doing this, the user will not feel the seal at all.
3. As i mentioned in event check in parallel #4289, and this https://filecoinproject.slack.com/archives/CP50PPW2X/p1602296605244900. In the current lotus implementation, after the number of deals has grown to a certain level, it will not continue to handle the storage deal correctly. I stopped receiving transactions because of this problem before this pr. It ran for a long time after the pr modification, and the same problem still appeared after the transaction volume increased. Now I have to stop the deal reception again. When I have time I will continue to try to solve this problem, but I think this problem should be more concerned, because it causes the network to be unable to effectively process data storage, which is very serious. if anyone try to investigate and need log or something，I am happy to help.

@whyrusleeping @hannahhoward