Re: Memory leak because of fragmented Large Object Heap?

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From: David Browne (meat_at_hotmail.com)
Date: 03/02/05 

Date: Wed, 2 Mar 2005 14:46:25 -0600

"Jon Skeet [C# MVP]" <skeet@pobox.com> wrote in message
news:MPG.1c9027b6a3edf92c98be07@msnews.microsoft.com...
> Zeng <Zeng5000@hotmail.com> wrote:
>> hm, the article says "never compacted" for LOH
>
> Yes, but as Henning was saying, "never compacted" doesn't mean "never
> collected". There's a big difference.
>
> Large objects will be collected, and that space reused if there are
> suitable new large objects created. What won't happen is the space
> between two uncollected large objects being compacted.
>

Also when they say "never compacted", that doesn't mean that the LOH isn't
managed somehow. It means that it's not compacted evey time it's collected
and will tend to show some bloat over time. This is in contrast to the
generational heaps which are compacted after each collection. I've only
ever seen about 20% bloat with the LOH. Whether that's because it's
periodically compacted or just the behavior of the heap allocation logic is
an implementation detail.

So although the large object heap will develop slack space which you won't
be able to use, I wouldn't consider this a "Memory Leak" unless the amount
of slack space in the LOH failed to level off at some reasonable percentage
of the LOH size.

David

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