From owner-freebsd-hackers@FreeBSD.ORG  Wed Jan  6 22:17:37 2010
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Date: Wed, 6 Jan 2010 13:49:44 -0800
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From: shrivatsan <shrivatsan@gmail.com>
To: freebsd-hackers@freebsd.org
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Subject: Question regarding memory disks
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Hi,

I have configured a malloc-backed memory disk, and I mount the device on to
the file system. I write some data onto the file system. I see that the free
memory indicated by kmem_map_free goes down, and this is proportional to the
size of the data written. However, even after removing all the
data, kmem_map_free doesn't seem to go up. Its only after detaching the
memory disk does the free memory go up. May I know the reason for this
behavior?


Thanks,
-shrivatsan