Re: [jgit-dev] .pack file locks not released when PackedGitMMAP=true

[Shawn Pearce <spearce@xxxxxxxxxxx>]

On Thu, Dec 20, 2012 at 12:58 PM, Mike Youngstrom <youngm@xxxxxxxxx> wrote:
> I ran into another instance of not being able to delete a cloned repository
> in windows.  This one appears linked to the use of "PackedGitMMAP".  Is this
> a known problem with trying to use virtual memory mapping?

Yes. The problem is the JVM does not release the memory mapping until
the mapping is garbage collected by the Java GC. This can happen at
any time in the future, possibly never if there is insufficient memory
pressure to force the GC to really look for garbage and reclaim. This
is why we disable the feature by default, we can't predict when the
JVM will finally release the file.

> In this test case if I "setPackedGitMMAP=false" then the repository is
> deleted successfully.

Yes. This is why this is the default.