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From: Erik J Groeneveld <erik@cq2.nl>
To: Andrew Haley <aph@redhat.com>
Cc: "java@gcc.gnu.org" <java@gcc.gnu.org>
Subject: Re: GC leaks debugging
Date: Fri, 15 Apr 2011 07:32:00 -0000	[thread overview]
Message-ID: <3EEDD501-73F7-4BC3-BA9B-E5FA4E6E4F73@cq2.nl> (raw)
In-Reply-To: <4DA6D14F.1080503@redhat.com>



Op 14 apr. 2011 om 12:49 heeft Andrew Haley <aph@redhat.com> het volgende geschreven:

>>> Why do you want to munmap, anyway?  Are you running out of swap space?
>> 
>> Well, I assume that if the GC unmaps a page (hblk), it can always be
>> mapped at any other location when a new block is needed, effectively
>> circumventing fragmentation completely.
> 
> AFAIK it just returns the memory to the OS;

It turns out it doesn't. It remaps it as not accessible. And it is only doing so after the block hasn't been used for a while. 
And there is some complicated code that seems to remap all such blocks into a larger block.

> I don't think it affects
> anything else.

I am still hoping it does. ;-)

Erik


  reply	other threads:[~2011-04-15  7:32 UTC|newest]

Thread overview: 42+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2011-04-01  8:39 Erik Groeneveld
2011-04-01  8:45 ` Andrew Haley
2011-04-01  9:03   ` Erik Groeneveld
2011-04-01  9:34     ` Andrew Haley
2011-04-02  0:27       ` Boehm, Hans
2011-04-02  9:39         ` Erik Groeneveld
2011-04-03 17:15           ` Erik Groeneveld
2011-04-03 18:00             ` Erik Groeneveld
2011-04-04  8:13               ` Andrew Haley
2011-04-04  8:53                 ` Erik Groeneveld
2011-04-04  9:48                   ` Andrew Haley
2011-04-05  4:44                     ` Boehm, Hans
2011-04-05  8:58                       ` Andrew Haley
2011-04-05  6:50                     ` Erik Groeneveld
2011-04-05  9:02                       ` Andrew Haley
2011-04-05 12:02                         ` Erik Groeneveld
2011-04-05 12:55                           ` Andrew Haley
2011-04-06 14:30                             ` Erik Groeneveld
2011-04-06 18:33                               ` Andrew Haley
2011-04-06 18:39                                 ` David Daney
2011-04-07 17:43                                 ` Erik Groeneveld
2011-04-08  8:12                                   ` Erik Groeneveld
2011-04-08 13:56                                   ` Andrew Haley
2011-04-08 15:35                                     ` David Daney
2011-04-08 15:53                                       ` Erik Groeneveld
2011-04-08 15:57                                         ` Andrew Haley
2011-04-08 15:48                                     ` Erik Groeneveld
2011-04-09  1:17                                     ` Boehm, Hans
2011-04-09  8:47                                       ` Andrew Haley
2011-04-09 10:56                                       ` Erik Groeneveld
2011-04-10 11:03                                         ` Erik Groeneveld
2011-04-12 18:43                                           ` Erik Groeneveld
2011-04-13  8:11                                             ` Andrew Haley
2011-04-13 12:11                                               ` Bryce McKinlay
2011-04-13 14:27                                                 ` Andrew Haley
2011-04-14  8:36                                               ` Erik Groeneveld
2011-04-14  8:43                                                 ` Andrew Haley
2011-04-14 10:02                                                   ` Erik Groeneveld
2011-04-14 10:50                                                     ` Andrew Haley
2011-04-15  7:32                                                       ` Erik J Groeneveld [this message]
2011-04-01 17:41 ` David Daney
2011-04-02 16:21   ` Erik Groeneveld

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