**UPDATE: I'm pretty confident that this has been addressed by the following pull request - https://github.com/sproutcore/sproutcore20/pull/174
In our main application, we're experiencing significant performance issues with IE 7/8 after a small amount of usage. The performance degrades very quickly, to the point where long running script warnings are presented by IE to the user. We've attempted to reproduce this issue in a very basic application (this), to help in debugging and hopefully fixing what appears to be a memory leak in Sproutcore collection views when underlying bound data is refreshed, causing the view contents to update.
- Load index.html
- Hit the 'Refresh View' button
- Take a snapshot of the memory profile
- Repeat several times and then view comparisons of memory snapshots between refreshes of the view data.
- Each snapshot diff shows many thousand more objects created than deleted, accumulating over time, despite that the same number of views are rendered on each refresh.
While it isn't the main point of this particular test, there's another interesting thing that happens with the store. If you try to unload all records of a type from the store before performing the remote query, the time of each view refresh will grow significantly each time. I suspect this is a datastore issue though.
To reproduce, uncomment the line in main.js App.Datasource.refresh()
/* store.unloadRecords(query.recordType) */
There are two other branches that show variants of the problem...
The second branch called 'no_handlebars', just overrides render instead of using a template for each item in the collection. This one reduces the number of accumulating objects but doesn't prevent it. One thing to note is that in master and no_handlebars branches, I am loading new records into the store on each view refresh so there will be some natural accumulation of objects due to this.
I've created a second branch that strips everything back even further called 'basic_paging'. This does a single query and then lets you page through the results, assigning the sliced array to the controller content each time. This reduces the number of objects that accumulate each time (partly due to the fact that less items are being rendered each time) but they still accumulate.