[<prev] [next>] [<thread-prev] [day] [month] [year] [list]
Message-ID: <alpine.LFD.2.00.1112191516400.30656@dhcp-27-109.brq.redhat.com>
Date: Mon, 19 Dec 2011 15:17:08 +0100 (CET)
From: Lukas Czerner <lczerner@...hat.com>
To: Lukas Czerner <lczerner@...hat.com>
cc: "Theodore Ts'o" <tytso@....edu>,
Ext4 Developers List <linux-ext4@...r.kernel.org>
Subject: Re: [PATCH 07/10] libext2fs: use the rbtree bitmap by default when
initializing a file system
On Mon, 19 Dec 2011, Lukas Czerner wrote:
> On Sun, 18 Dec 2011, Theodore Ts'o wrote:
>
> > This change causes the max resident memory of mke2fs, as reported by
> > /usr/bin/time, to drop from 9296k to 5328k when formatting a 25
> > gig volume.
>
> Just for the record, creating bigger file system will show much bigger
> difference. For example when creating 100T file system with the old
> bitarray backend it will consume 14GB of memory, but with the new rbtree
> backend it will only consume 220 MB (reported by /usr/bin/time).
>
> Actually the real allocated memory according to valgrind is 54MB for
> rbtree and 3.74GB for bitmap backend. I assume that /usr/bin/time shows
> amount of dirtied memory pages ??
>
> A while ago I have done some testing on older version of e2fsprogs with
> rbtree patches. The numbers might differ now, but the overall difference
> between rbtree and bitmaps should be roughly the same. Here are some
> graphs:
>
> http://people.redhat.com/lczerner/e2fsprogs_memory/graphs.pdf
Also the testing has been done on e2fsck, rather than mke2fs.
>
> Thanks!
> -Lukas
>
> >
> > Signed-off-by: "Theodore Ts'o" <tytso@....edu>
> > ---
> > lib/ext2fs/initialize.c | 1 +
> > 1 files changed, 1 insertions(+), 0 deletions(-)
> >
> > diff --git a/lib/ext2fs/initialize.c b/lib/ext2fs/initialize.c
> > index b050a0a..a63ea18 100644
> > --- a/lib/ext2fs/initialize.c
> > +++ b/lib/ext2fs/initialize.c
> > @@ -112,6 +112,7 @@ errcode_t ext2fs_initialize(const char *name, int flags,
> > fs->magic = EXT2_ET_MAGIC_EXT2FS_FILSYS;
> > fs->flags = flags | EXT2_FLAG_RW;
> > fs->umask = 022;
> > + fs->default_bitmap_type = EXT2FS_BMAP64_RBTREE;
> > #ifdef WORDS_BIGENDIAN
> > fs->flags |= EXT2_FLAG_SWAP_BYTES;
> > #endif
> >
> --
> To unsubscribe from this list: send the line "unsubscribe linux-ext4" in
> the body of a message to majordomo@...r.kernel.org
> More majordomo info at http://vger.kernel.org/majordomo-info.html
>
--
--
To unsubscribe from this list: send the line "unsubscribe linux-ext4" in
the body of a message to majordomo@...r.kernel.org
More majordomo info at http://vger.kernel.org/majordomo-info.html
Powered by blists - more mailing lists