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ramkiciti
14 May 2012, 6:59 AM
Hi,
One of my team members researched Ext JS 4.x and says it is very premature to use this product now because it has GC issues and hence severe performance problems. Could you please let me know if it is true and the ext js team is working for an improved version to fix the performance issue. I googled up for Ext JS 4 GC issues and nothing came up.

joeri
15 May 2012, 2:44 AM
I think you need to ask your team member where they got their data.

ramkiciti
15 May 2012, 4:35 AM
I think you need to ask your team member where they got their data.

He said, he did a Proof of Concept and while running the code, it was very slow attributing to GC. I dont even know how to see GC in browsers rendering Java Scripts. He also claims that it happens with Ext JS 4 examples [showcase]. Has there been any such performance issues known with Ext JS 4 unlike the previous versions [ Ext JS 3.4]. How does one find out the GC activity of the browser if a GC thread runs at all like in a JVM.

joeri
15 May 2012, 6:05 AM
You can't directly observe the garbage collector in any browser I know. You can observe the memory usage in chrome's memory timeline, and you can do heap snapshots in chrome's inspector. Both give an indirect way of observing memory usage over time, which can give an indication of garbage collection activity.

I suspect that the performance issues he's seeing have more to do with DOM interaction than with GC.

ramkiciti
15 May 2012, 6:08 AM
You can't directly observe the garbage collector in any browser I know. You can observe the memory usage in chrome's memory timeline, and you can do heap snapshots in chrome's inspector. Both give an indirect way of observing memory usage over time, which can give an indication of garbage collection activity.

I suspect that the performance issues he's seeing have more to do with DOM interaction than with GC.

thanks for your response. Could you please elaborate on "DOM interaction with GC". More so, is there any significant performance issues with Ext JS 4 like my teammate claims.

joeri
15 May 2012, 11:39 PM
I said the performance issues are likely due to DOM interaction instead of GC.

It's the rendering of the content to the page that slows ExtJS apps down, not the execution of javascript code.

I'm not saying ExtJS doesn't have performance issues, but it depends very much on the context of what you're doing whether you find performance acceptable or not.