Memory leak in v9.0.2 (OSX)

+Continued from+ http://www.dbvis.com/forum/thread.jspa?threadID=4216 The memory warning dialog appeared today, with slightly different behavior: First, the two open tabs with the most use and rows actually showed a believable amount of memory consumed, 12-13 MB in both cases. When the dialog was shown, the memory meter was around 450M of 505M. I closed the two tabs consuming the most memory through the memory warning dialog, and the memory meter was reduced by about 44MB, and clicked the GC icon, but within a few seconds the memory warning dialog was presented again. I dismissed it, and closed the remaining tabs, but with no tabs open, and the GC run again, the memory warning dialog continued to be displayed, and a restart of DbVis was required. Interestingly, at no point on dismissing the warning dialog was I presented with an "Are you sure?" dialog, which made the orderly shutdown process easier. Product: DbVisualizer Pro 9.0.2 Build: #1912 (2012/12/18 10:21) Java VM: Java HotSpot(TM) 64-Bit Server VM Java Version: 1.6.0_37 Java Vendor: Apple Inc. OS Name: Mac OS X OS Arch: x86_64 OS Version: 10.8.2 Edited by: MattK on Dec 21, 2012 3:54 PM

I have turned the assistive option off, and will see how it goes. As far as the dialog goes, closing tabs from this dialog never helps. They all show less than 1MB used, and even when closing them all, the warning persists. Whatever is consuming memory, DbVis is not showing that it is specific to a particular tab.

Hi Matt, So sorry to hear it is still a problem. Just to be clear, the problem disappear if you disable the assistive devices support again, right? If so, we need to look into how we can work around the memory leaks it causes. Regarding the modal dialog, I agree with you as things stand right now since it doesn't work as intended. The dialog is modal because once you reach the memory utilization limit, anything you do can cause the GUI to freeze and really make it impossible to close things down in an orderly fashion. The only thing you can safely do is to close tabs and stop jobs, and both those things can be done from the dialog. If there are pending editor edits, you get the chance to save them when you close the tab from the dialog, for instance. The problem is that currently there are cases when closing tabs and stopping jobs do not release memory due to bugs. That's why you end up in the situation you describe. If the memory was released, as it should, you would be able to click Continue without having the dialog pop up again. Until we have found a solution for the bugs, we may add a Shutdown button in the dialog to handle this. Best Regards, Hans

Still not fixed. I turned the assistive option back on, and today encountered the memory warning. The addition of the option to not show the warning again only helps a small amount, because once the warnings start, they repeat immediately after being dismissed, making it difficult to save tabs and perform an orderly shutdown. Modal dialogs are a terrible idea, and especially bad here, because the repeated warnings block the UI, preventing me from properly saving and closing the app. I had to force terminate DbVis today being unable to get access to anything but the memory warning. I will also add that in this DbVis session, all recordsets I was working with were less than 5,000 rows, compared to the larger sets in past reports. Edited by: MattK on Feb 12, 2013 2:07 PM

Hi Matt, Thanks for your help with this. We did a number of smaller changes in 9.0.3 related to releasing references to objects so their memory can be reused. I just tested enabling access for assistive devices again, and it seems like the changes we made also makes it unnecessary to disable access. Can you please see if that is true for your cases as well? Best Regards, Hans

> We realize that disabling the assistive devices support is not an option for all, so we will continue to look for other ways to resolve the problem. Please do! So far, memory seems to be in check, and while (for me) DbVisualizer is more important than a window manager add-on, they are nice to have for managing several concurrently used apps.

I installed 9.0.3 right away, and so far it is working well. I am not exercising it as hard this week yet, but will report my findings.

Hi Matt, Thanks for letting us know. We realize that disabling the assistive devices support is not an option for all, so we will continue to look for other ways to resolve the problem. Have you had a chance to test 9.0.3? Any difference? Best Regards, Hans

I had the assistive option on to support a Mac window manager tool - Moom. Several of these exist, and they apparently use the assistive API to move windows around the desktop.

Hi Matt, In many of the cases where I have seen a problem, references to old, closed, result sets are held by instances of a Java class named apple.awt.CAccessible. This class is used to interact with the Mac OS X Accessibilty features, and if you google on it, you find lots of reports of it causing all sorts of problems. Disabling the associative devices support means that the Java VM does not use this class, and hence, the problem with it references old data disappears. I will try to find a way to disable the support programmatically just for the DbVisualizer JVM. We have found a few other odd references to old data from both our own and internal Java classes and have tweaked the code to avoid them. It makes things run better and will be included in the next maintenance release. We will, however, continue to monitor this area and add tweaks as needed. Best Regards, Hans

I did have it enabled. I recall some reason for setting it - some feature hack perhaps. I have disabled it ans will see if it makes a difference. This is an unusual cause, especially for a Java app. Can you share how it relates?

Hi Matt, I believe I have found a key cause for the memory leak you see. Please open Mac OS X System Preferences and select Accessibility. If "Enable access for assistive devices" is enabled, disable it. Please let us know if you notice a difference. Best Regards, Hans

Hi Matt, Thanks for keeping us informed. We're still looking into this issue. Best Regards, Hans

I have had 3 out of memory issues today, each requiring a full restart of the application. As before, the OOM dialog only serves to tell me I must restart, and I have to time the shutdown in between re-appearances of this dialog. Perhaps a delay in between presentations would be useful. In this case, I was running a query that returns about 35,000 records to DbVis. This is a high number of rows, but I was tracking down a data problem, and the ability to quickly browse for patterns is needed. Product: DbVisualizer Pro 9.0.2 Build: #1912 (2012/12/18 10:21) Java VM: Java HotSpot(TM) 64-Bit Server VM Java Version: 1.6.0_37 Java Vendor: Apple Inc. OS Name: Mac OS X OS Arch: x86_64 OS Version: 10.8.2

Hi Matt, Okay, thanks for the clarification. Best Regards, Hans

The memory warning was presented without running another select, but in response to saving an unsaved query in one of the unclose tabs.