Inspector now uses the app manager to open autoplot windows

[pfafflabatuiuc]

Inspectr now uses the app manager to open new autoplot window in separate process.

[wpfff]

@astafan8 and @jenshnielsen would one of you be able to have a look at this?
we have been working a bit on launching plots more robustly. they are now each running in a separate process, which solves #298 rigorously and will make some other features we have in mind easier to implement (like #240 for example).

it works great as is in our lab on monitr, but this PR is also moving this to inspectr. but since we don't use the qcodes database here it'd be great to get your opinion.

[jenshnielsen]

Thanks @pfafflabatuiuc and @wpfff I will try to have a look asap

[wpfff]

great, thanks! no immediate rush, but definitely looking forward to hear your opinion.

[astafan8]

@wpfff i've tested it just now, it seems to work, and indeed launches separate processes per plot and all.

however opening a new plot window is noticable slower that with the original implementation (say 1-2s vs 5s on my machine). i did not profile the code, but perhaps it's the price to pay for launching a separate process and all. Did you notice a slowdown when you migrated to the app manager?

@jenshnielsen for info

[wpfff]

interesting, thanks for having a look @astafan8 -- we can have a closer look at that. i think for our non-qcodes db backend i didn't notice that.
plus we started migrating a lot of measurement machines to linux, where i in general had the feeling things are pretty snappy.

@marcosfrenkel could you have a look how speed compares for you between the old and new way? (both qcodes/hdf5 backends, and maybe also linux vs windows?)

[marcosfrenkel]

@astafan8 @jenshnielsen It seems like the slowdown is the price you pay for starting new processes. Trying it with monitr and ddh5 files, no matter what way you use to start a new process with autoplot (from a terminal or an app) there is a slowdown when starting the new process and loading the data than doing it in the same process.

I tested a few different combinations and it seems like on my computer with using matplotlib it takes somewhere about 1~1.5 seconds extra to open a new process instead of plotting it in the same one. The new process slowdown is bigger for the Qcodes database than the ddh5 files we use though.

[wpfff]

we here currently think this is acceptable (the fact that each plotting window has its own process makes the entire app more robust and each autoplot window a bit faster).

But before merging it'd be great to get an explicit OK @jenshnielsen and @astafan8 :)

It would of course also be possible to make this optional through a user setting.

[jenshnielsen]

@wpfff Will do some real world testing and come back to you

[wpfff]

@jenshnielsen did you ever manage to look at this?