UI progress

[casperdcl]

• add progress to other uses of stage.dump
• profile repo.check_modified_graph(), stage.save(), stage.dump() etc to find out what other functions are slow, perhaps add progress for them too
  • md5sums only take about 10% of the total time. There must be other more time consuming functions
• make sure that we show HINT message to enable cache optimization properly when copy is taking too long already
• continues add: cleanup and improve output #2699
• continues UI progress cleanup #2846

[casperdcl]

make sure that we show HINT message to enable cache optimization properly when copy is taking too long already

@shcheklein is this done already? I seem to recall it may have been mentioned in a different PR.

[shcheklein]

@casperdcl so, I'm not sure to be honest. It's super important and should be done in a way that is visible when certain thresholds are passed. I don't remember what is current policy even. I would revisit them.

[efiop]

Current policy is per-link, so it only shows a warning if one individual link takes longer than 10 seconds. It doesn't account for like, 2 links of 5 seconds or anything like that. Feels like we could simply lower the threshold to improve the experience, but need to make protected = True by default first.

[shcheklein]

First thing I would say for this ticket is make sure that it is visible clearly with all these changes to progress bars and whatnot.

[efiop]

Clsoing as stale. Now working on pre-requisites like libifying dvc/objects and creating events, which will then enable proper ui/pbars.