From: Andrew Morton <akpm@linux-foundation.org>
To: Johannes Stezenbach <js@sig21.net>
Cc: linux-mm@kvack.org, linux-kernel@vger.kernel.org,
Thomas Gleixner <tglx@linutronix.de>
Subject: Re: huge debug_objects_cache. swapping but 25% mem free
Date: Fri, 3 Feb 2012 15:12:18 -0800 [thread overview]
Message-ID: <20120203151218.59ceb1c1.akpm@linux-foundation.org> (raw)
In-Reply-To: <20120201182932.GA15518@sig21.net>
On Wed, 1 Feb 2012 19:29:32 +0100
Johannes Stezenbach <js@sig21.net> wrote:
> On Mon, Jan 30, 2012 at 04:40:48PM +0100, Johannes Stezenbach wrote:
> >
> > According to slabtop debug_objects_cache eats half the
> > memory, is this expected? The Kconfig help text does not
> > suggest it.
>
> FWIW, today after running full backup using rsync:
>
> OBJS ACTIVE USE OBJ SIZE SLABS OBJ/SLAB CACHE SIZE NAME
> 4025450 4025447 99% 0.36K 183977 22 1471816K debug_objects_cache
> 170266 87241 51% 1.74K 9645 18 308640K ext3_inode_cache
> 54855 40215 73% 0.58K 2034 27 32544K dentry
> 38124 12474 32% 0.42K 2119 18 16952K buffer_head
> 17794 17464 98% 0.51K 574 31 9184K sysfs_dir_cache
> 11434 8494 74% 0.87K 713 18 11408K radix_tree_node
> 11400 5570 48% 0.38K 570 20 4560K kmalloc-64
>
> /sys/kernel/debug/debug_objects/stats:
> max_chain :870
> warnings :0
> fixups :0
> pool_free :258
> pool_min_free :252
> pool_used :4025193
> pool_max_used :4025195
>
>
> then after "echo 3 >/proc/sys/vm/drop_caches":
>
> OBJS ACTIVE USE OBJ SIZE SLABS OBJ/SLAB CACHE SIZE NAME
> 4030488 4030485 99% 0.36K 184206 22 1473648K debug_objects_cache
> 17955 9071 50% 0.58K 665 27 10640K dentry
> 17763 17455 98% 0.51K 573 31 9168K sysfs_dir_cache
> 9408 9156 97% 0.33K 392 24 3136K kmalloc-8
>
>
> I'm still not sure if this is normal behaviour of DEBUG_OBJECTS or a bug?
Bug. It appears that you hadn't been using CONFIG_DEBUG_OBJECTS before
3.2 so we don't know if it is a regression.
prev parent reply other threads:[~2012-02-03 23:12 UTC|newest]
Thread overview: 3+ messages / expand[flat|nested] mbox.gz Atom feed top
2012-01-30 15:40 huge debug_objects_cache. swapping but 25% mem free Johannes Stezenbach
2012-02-01 18:29 ` Johannes Stezenbach
2012-02-03 23:12 ` Andrew Morton [this message]
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