Bug SSC-3480
2 votes

loss of changes

Created by Davide on 10/24/2017 7:00 PM Last Updated by Martin Kraska on 12/30/2017 3:58 PM
Logged: 0   (hrs)


sometimes something like an history undo is triggered by user inputs (keyboard, mouse), the browser page is reloaded and recent changes are lost (history messed up)

esier for me to trigger it in chrome, happend even in firefox though


probably the issue described here



    Martin Kraska (Saturday, December 30, 2017 3:58 PM) #

I also experience loss of changes. They seam to be triggered by highlighting one or several regions in light blue and then pressing Del or Ctrl-X. The loss is restricted to the last deliberate save using the toolbar button, regardless of how long ago this happened.

This is an example file where this happened frequently: https://en.smath.info/cloud/worksheet/N4gAxVxV

I experienced more annoying interface problems:

- Images can't be inserted repeatedly unless the sheet is reloaded using the browser refresh button. Without doing this, the user experience is that the insert picture menu item just doesn't work any more.

- The visibility of stacked regions sometimes is messed up. If you move text regions around (e.g. if you want to annotate an image with math regions) then they are sometimes behind the image (in the background) and sometimes in the foreground. This seem to be dependent on where the region originally has been created. Also, this can change if the file is reloaded or re-opened.

- Annotations (math regions with single variable names only) aren't formatted properly (italicised). You can enforce italic style by evaluating the region and subsequently deleting the result. This, however, doesn't seem to persist.

In general, these problems are hard to bracket, because of interference with browser cache. You can only be sure to see the persistent state of your worksheet if you share a link and open it in another browser instance (not just in another tab). I even switch between windows and linux running in a virtual machine.

    smath (Monday, October 30, 2017 3:28 PM) #

Normally application does save any change in 3 seconds after this change is done. If user will do another change before 3 seconds expired, save of changes will be aborted and new 3 seconds will start counting.

This logic allows to minimize number of requests to server and also minimizes usage of resources required to perform data serialization and saving changes into the database.

Reported issue may be possible because of SMath Studio in the Cloud application is restarted before changes saved during session alive. The following cases are possible:

  1. New version of the application deployed to the server;
  2. Some critical unhandled exception happened in the app.

So, yes, observation exists, but all the stability improvements done for SMath Studio will also do SMath Studio in the Cloud much more stable. Regarding deployment: I will think what can be done to not disturb users during this process.

Thank you for the report!

    Kim Koch Rasmussen (Monday, October 30, 2017 1:28 PM) #

Can NOT reproduce the bug in Explore, but happen a lot in Chrome...

    Kim Koch Rasmussen (Monday, October 30, 2017 12:44 PM) #

Yes, this is excatly this as described on the link