Databases
StackOverflow2013
Postsdbo
PO
 

Note that there are some explanatory texts on larger screens.

plurals
  1. PO
    primarykey
    data
    text
    <p>I want to emphasize Brian's point in his comment, because it is important.</p> <p>Finalizers are not deterministic destructors like in C++. As others have pointed out, there is no guarantee of when it will be called, and indeed if you have enough memory, if it will <em>ever</em> be called.</p> <p>But the bad thing about finalizers is that, as Brian said, it causes your object to survive a garbage collection. This can be bad. Why?</p> <p>As you may or may not know, the GC is split into generations - Gen 0, 1 and 2, plus the Large Object Heap. Split is a loose term - you get one block of memory, but there are pointers of where the Gen 0 objects start and end. </p> <p>The thought process is that you'll likely use lots of objects that will be short lived. So those should be easy and fast for the GC to get to - Gen 0 objects. So when there is memory pressure, the first thing it does is a Gen 0 collection. </p> <p>Now, if that doesn't resolve enough pressure, then it goes back and does a Gen 1 sweep (redoing Gen 0), and then if still not enough, it does a Gen 2 sweep (redoing Gen 1 and Gen 0). So cleaning up long lived objects can take a while and be rather expensive (since your threads may be suspended during the operation).</p> <p>This means that if you do something like this:</p> <pre><code>~MyClass() { } </code></pre> <p>Your object, no matter what, will live to Generation 2. This is because the GC has no way of calling the finalizer during garbage collection. So objects that have to be finalized are moved to a special queue to be cleaned out by a different thread (the finalizer thread - which if you kill makes all kinds of bad things happen). This means your objects hang around longer, and potentially force more garbage collections.</p> <p>So, all of that is just to drive home the point that you want to use IDisposable to clean up resources whenever possible and seriously try to find ways around using the finalizer. It's in your application's best interests.</p>
    singulars
    1. This table or related slice is empty.
    1. POWill the Garbage Collector call IDisposable.Dispose for me?
      singulars
      1. PTQuestion
    1. PTAnswer
    1. USMartin Capodici
    1. USCory Foy
    plurals
    1. This table or related slice is empty.
    1. This table or related slice is empty.
    1. This table or related slice is empty.
    1. This table or related slice is empty.
    1. VO
      singulars
      1. PO
      1. This table or related slice is empty.
      1. VTUpMod
    2. VO
      singulars
      1. PO
      1. This table or related slice is empty.
      1. VTUpMod
    3. VO
      singulars
      1. PO
      1. This table or related slice is empty.
      1. VTUpMod
    1. COI agree that you want to use IDisposable whenever possible, but you should also have a finalizer that calls a dispose method. You can call GC.SuppressFinalize() in IDispose.Dispose after calling your dispose method to ensure your object doesn't get put in the finalizer queue.
      singulars
      1. PO
      1. USjColeson
    2. COGenerations are numbered 0-2, not 1-3, but your post is otherwise good. I would add to it, though, that any objects referenced by your object, or any objects referenced by those, etc. will also be protected against garbage-collection (though not against finalization) for at another generation. Thus objects with finalizers should not hold references to anything not needed for finalization.
      singulars
      1. PO
      1. USsupercat
    3. CO[Reference (of a kind) for generation numbers](http://stackoverflow.com/questions/2257563/what-are-the-generations-in-garbage-collection)
      singulars
      1. PO
      1. USLightness Races in Orbit
 

Querying!

 
Guidance
A row detail

Detail views are divided into sections. All the information in the data section comes from columns in the selected row. The other sections display data from other, related rows.

Related data can be related in a to-one or a to-many fashion. Captions of data related in a to-many fashion link to a list view showing a filtered view of the table.

Try moving around until you find a non-empty to-many entry and click on the label to get to one. You can move back to the root by clicking on the database name in the header.

SQuiL has stopped working due to an internal error.

If you are curious you may find further information in the browser console, which is accessible through the devtools (F12).

Reload