xattr performance

Hi,

a while ago I was setting & reading extended attributes to ~25000 files 
in a directory structure on an XFS filesystem. The files were usually a 
few MB in size, but some where up to 2GB in size.

Anyway, I *felt* that setting or reading these xattrs was going very
slowly. While the storage may be not the fastest, stat()'ing these
files was fine, but getfattr/setfattr took very long.

I got curious and while it turned out that the slowness was related to the 
wrapper script I used to read/set those values, I created a little test 
suite to 1) create a few thousand files and 2) do xattr operations on 
them and see if xattr performance was filesystem specific:

   http://nerdbynature.de/bits/xattr/

Not very sophisticated, true. But it was interesting to see that 
ext3/ext4/xfs behaved kinda well for all these tests; btrfs/jfs/reiserfs
sometimes took way longer than the others.

Christian.
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[GIT PULL] jfs for 3.10

The following changes since commit 5f243b9b46a22e5790dbbc36f574c2417af49a41:

  Merge tag 'arm64-fixes' of
git://git.kernel.org/pub/scm/linux/kernel/git/cmarinas/linux-aarch64 (2013-01-04 10:41:54 -0800)

are available in the git repository at:

  git://github.com/kleikamp/linux-shaggy.git tags/jfs-3.10

for you to fetch changes up to 73aaa22d5ffb2630456bac2f9a4ed9b81d0d7271:

  jfs: fix a couple races (2013-05-01 11:16:59 -0500)

----------------------------------------------------------------
Dave Kleikamp (1):
      jfs: fix a couple races

Nickolai Zeldovich (1):
      jfs: avoid undefined behavior from left-shifting by 32 bits

 fs/jfs/inode.c      | 2 +-
 fs/jfs/jfs_imap.c   | 2 +-
 fs/jfs/jfs_logmgr.c | 3 ++-
 3 files changed, 4 insertions(+), 3 deletions(-)

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Negative value for inode???

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_______________________________________________
Jfs-discussion mailing list
Jfs-discussion <at> lists.sourceforge.net
https://lists.sourceforge.net/lists/listinfo/jfs-discussion

Re: [PATCH] jfs: avoid undefined behavior from left-shifting by 32 bits

On 01/05/2013 01:19 PM, Nickolai Zeldovich wrote:
> Shifting a 32-bit int by 32 bits is undefined behavior in C, and
> results in different behavior on different architectures (e.g., x86
> and PowerPC).  diAlloc() in fs/jfs/jfs_imap.c computes a mask using
> 0xffffffffu<<(32-bitno), which can left-shift by 32 bits.  To avoid
> unexpected behavior, explicitly check for bitno==0 and use a 0 mask.

Thanks. Pushed to
git://github.com/kleikamp/linux-shaggy.git jfs-next

Shaggy

> 
> Signed-off-by: Nickolai Zeldovich <nickolai <at> csail.mit.edu>
> ---
>  fs/jfs/jfs_imap.c |    2 +-
>  1 file changed, 1 insertion(+), 1 deletion(-)
> 
> diff --git a/fs/jfs/jfs_imap.c b/fs/jfs/jfs_imap.c
> index 6ba4006..f7e042b 100644
> --- a/fs/jfs/jfs_imap.c
> +++ b/fs/jfs/jfs_imap.c
>  <at>  <at>  -1493,7 +1493,7  <at>  <at>  int diAlloc(struct inode *pip, bool dir, struct inode *ip)
>  		/* mask any prior bits for the starting words of the
>  		 * summary map.
>  		 */
> -		mask = ONES << (EXTSPERSUM - bitno);
> +		mask = (bitno == 0) ? 0 : (ONES << (EXTSPERSUM - bitno));
>  		inosmap = le32_to_cpu(iagp->inosmap[sword]) | mask;
>  		extsmap = le32_to_cpu(iagp->extsmap[sword]) | mask;
>  
> 

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[PATCH 12/21] jfs: drop vmtruncate

Removed vmtruncate

Signed-off-by: Marco Stornelli <marco.stornelli <at> gmail.com>
---
 fs/jfs/file.c  |    6 ++++--
 fs/jfs/inode.c |   20 ++++++++++++++------
 2 files changed, 18 insertions(+), 8 deletions(-)

diff --git a/fs/jfs/file.c b/fs/jfs/file.c
index 9d3afd1..dd7442c 100644
--- a/fs/jfs/file.c
+++ b/fs/jfs/file.c
 <at>  <at>  -119,9 +119,12  <at>  <at>  int jfs_setattr(struct dentry *dentry, struct iattr *iattr)
 	    iattr->ia_size != i_size_read(inode)) {
 		inode_dio_wait(inode);

-		rc = vmtruncate(inode, iattr->ia_size);
+		rc = inode_newsize_ok(inode, iattr->ia_size);
 		if (rc)
 			return rc;
+
+		truncate_setsize(inode, iattr->ia_size);
+		jfs_truncate(inode);
 	}

 	setattr_copy(inode, iattr);
 <at>  <at>  -133,7 +136,6  <at>  <at>  int jfs_setattr(struct dentry *dentry, struct iattr *iattr)
 }

 const struct inode_operations jfs_file_inode_operations = {
-	.truncate	= jfs_truncate,
 	.setxattr	= jfs_setxattr,
 	.getxattr	= jfs_getxattr,
 	.listxattr	= jfs_listxattr,
diff --git a/fs/jfs/inode.c b/fs/jfs/inode.c
index 4692bf3..b7dc47b 100644
--- a/fs/jfs/inode.c
+++ b/fs/jfs/inode.c
 <at>  <at>  -300,6 +300,16  <at>  <at>  static int jfs_readpages(struct file *file, struct address_space *mapping,
 	return mpage_readpages(mapping, pages, nr_pages, jfs_get_block);
 }

+static void jfs_write_failed(struct address_space *mapping, loff_t to)
+{
+	struct inode *inode = mapping->host;
+
+	if (to > inode->i_size) {
+		truncate_pagecache(inode, to, inode->i_size);
+		jfs_truncate(inode);
+	}
+}
+
 static int jfs_write_begin(struct file *file, struct address_space *mapping,
 				loff_t pos, unsigned len, unsigned flags,
 				struct page **pagep, void **fsdata)
 <at>  <at>  -308,11 +318,8  <at>  <at>  static int jfs_write_begin(struct file *file, struct address_space *mapping,

 	ret = nobh_write_begin(mapping, pos, len, flags, pagep, fsdata,
 				jfs_get_block);
-	if (unlikely(ret)) {
-		loff_t isize = mapping->host->i_size;
-		if (pos + len > isize)
-			vmtruncate(mapping->host, isize);
-	}
+	if (unlikely(ret))
+		jfs_write_failed(mapping, pos + len);

 	return ret;
 }
 <at>  <at>  -326,6 +333,7  <at>  <at>  static ssize_t jfs_direct_IO(int rw, struct kiocb *iocb,
 	const struct iovec *iov, loff_t offset, unsigned long nr_segs)
 {
 	struct file *file = iocb->ki_filp;
+	struct address_space *mapping = file->f_mapping;
 	struct inode *inode = file->f_mapping->host;
 	ssize_t ret;

 <at>  <at>  -341,7 +349,7  <at>  <at>  static ssize_t jfs_direct_IO(int rw, struct kiocb *iocb,
 		loff_t end = offset + iov_length(iov, nr_segs);

 		if (end > isize)
-			vmtruncate(inode, isize);
+			jfs_write_failed(mapping, end);
 	}

 	return ret;
--

-- 
1.7.3.4

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[PATCH 12/21] jfs: drop vmtruncate

Removed vmtruncate

Signed-off-by: Marco Stornelli <marco.stornelli <at> gmail.com>
---
 fs/jfs/file.c  |    6 ++++--
 fs/jfs/inode.c |   20 ++++++++++++++------
 2 files changed, 18 insertions(+), 8 deletions(-)

diff --git a/fs/jfs/file.c b/fs/jfs/file.c
index 9d3afd1..dd7442c 100644
--- a/fs/jfs/file.c
+++ b/fs/jfs/file.c
 <at>  <at>  -119,9 +119,12  <at>  <at>  int jfs_setattr(struct dentry *dentry, struct iattr *iattr)
 	    iattr->ia_size != i_size_read(inode)) {
 		inode_dio_wait(inode);

-		rc = vmtruncate(inode, iattr->ia_size);
+		rc = inode_newsize_ok(inode, iattr->ia_size);
 		if (rc)
 			return rc;
+
+		truncate_setsize(inode, iattr->ia_size);
+		jfs_truncate(inode);
 	}

 	setattr_copy(inode, iattr);
 <at>  <at>  -133,7 +136,6  <at>  <at>  int jfs_setattr(struct dentry *dentry, struct iattr *iattr)
 }

 const struct inode_operations jfs_file_inode_operations = {
-	.truncate	= jfs_truncate,
 	.setxattr	= jfs_setxattr,
 	.getxattr	= jfs_getxattr,
 	.listxattr	= jfs_listxattr,
diff --git a/fs/jfs/inode.c b/fs/jfs/inode.c
index 4692bf3..b7dc47b 100644
--- a/fs/jfs/inode.c
+++ b/fs/jfs/inode.c
 <at>  <at>  -300,6 +300,16  <at>  <at>  static int jfs_readpages(struct file *file, struct address_space *mapping,
 	return mpage_readpages(mapping, pages, nr_pages, jfs_get_block);
 }

+static void jfs_write_failed(struct address_space *mapping, loff_t to)
+{
+	struct inode *inode = mapping->host;
+
+	if (to > inode->i_size) {
+		truncate_pagecache(inode, to, inode->i_size);
+		jfs_truncate(inode);
+	}
+}
+
 static int jfs_write_begin(struct file *file, struct address_space *mapping,
 				loff_t pos, unsigned len, unsigned flags,
 				struct page **pagep, void **fsdata)
 <at>  <at>  -308,11 +318,8  <at>  <at>  static int jfs_write_begin(struct file *file, struct address_space *mapping,

 	ret = nobh_write_begin(mapping, pos, len, flags, pagep, fsdata,
 				jfs_get_block);
-	if (unlikely(ret)) {
-		loff_t isize = mapping->host->i_size;
-		if (pos + len > isize)
-			vmtruncate(mapping->host, isize);
-	}
+	if (unlikely(ret))
+		jfs_write_failed(mapping, pos + len);

 	return ret;
 }
 <at>  <at>  -326,6 +333,7  <at>  <at>  static ssize_t jfs_direct_IO(int rw, struct kiocb *iocb,
 	const struct iovec *iov, loff_t offset, unsigned long nr_segs)
 {
 	struct file *file = iocb->ki_filp;
+	struct address_space *mapping = file->f_mapping;
 	struct inode *inode = file->f_mapping->host;
 	ssize_t ret;

 <at>  <at>  -341,7 +349,7  <at>  <at>  static ssize_t jfs_direct_IO(int rw, struct kiocb *iocb,
 		loff_t end = offset + iov_length(iov, nr_segs);

 		if (end > isize)
-			vmtruncate(inode, isize);
+			jfs_write_failed(mapping, end);
 	}

 	return ret;
--

-- 
1.7.3.4

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[GIT PULL] jfs bug fix for 3.7

The following changes since commit 8d2b6b3ae280dcf6f6c7a95623670a57cdf562ed:

  Merge tag 'sh-for-linus' of git://github.com/pmundt/linux-sh (2012-10-16 19:24:00 -0700)

are available in the git repository at:

  git://github.com/kleikamp/linux-shaggy.git tags/jfs-3.7-2

for you to fetch changes up to 4e7a4b01222343481d8ff084dbef9b80f7089a19:

  jfs: Fix FITRIM argument handling (2012-10-17 09:18:38 -0500)

----------------------------------------------------------------
Bug fix: Fix FITRIM argument handling

----------------------------------------------------------------
Lukas Czerner (1):
      jfs: Fix FITRIM argument handling

 fs/jfs/jfs_discard.c | 16 ++++++++++------
 1 file changed, 10 insertions(+), 6 deletions(-)

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[PATCH 12/21] jfs: drop vmtruncate

Removed vmtruncate

Signed-off-by: Marco Stornelli <marco.stornelli <at> gmail.com>
---
 fs/jfs/file.c  |    6 ++++--
 fs/jfs/inode.c |   20 ++++++++++++++------
 2 files changed, 18 insertions(+), 8 deletions(-)

diff --git a/fs/jfs/file.c b/fs/jfs/file.c
index 9d3afd1..dd7442c 100644
--- a/fs/jfs/file.c
+++ b/fs/jfs/file.c
 <at>  <at>  -119,9 +119,12  <at>  <at>  int jfs_setattr(struct dentry *dentry, struct iattr *iattr)
 	    iattr->ia_size != i_size_read(inode)) {
 		inode_dio_wait(inode);

-		rc = vmtruncate(inode, iattr->ia_size);
+		rc = inode_newsize_ok(inode, iattr->ia_size);
 		if (rc)
 			return rc;
+
+		truncate_setsize(inode, iattr->ia_size);
+		jfs_truncate(inode);
 	}

 	setattr_copy(inode, iattr);
 <at>  <at>  -133,7 +136,6  <at>  <at>  int jfs_setattr(struct dentry *dentry, struct iattr *iattr)
 }

 const struct inode_operations jfs_file_inode_operations = {
-	.truncate	= jfs_truncate,
 	.setxattr	= jfs_setxattr,
 	.getxattr	= jfs_getxattr,
 	.listxattr	= jfs_listxattr,
diff --git a/fs/jfs/inode.c b/fs/jfs/inode.c
index 4692bf3..b7dc47b 100644
--- a/fs/jfs/inode.c
+++ b/fs/jfs/inode.c
 <at>  <at>  -300,6 +300,16  <at>  <at>  static int jfs_readpages(struct file *file, struct address_space *mapping,
 	return mpage_readpages(mapping, pages, nr_pages, jfs_get_block);
 }

+static void jfs_write_failed(struct address_space *mapping, loff_t to)
+{
+	struct inode *inode = mapping->host;
+
+	if (to > inode->i_size) {
+		truncate_pagecache(inode, to, inode->i_size);
+		jfs_truncate(inode);
+	}
+}
+
 static int jfs_write_begin(struct file *file, struct address_space *mapping,
 				loff_t pos, unsigned len, unsigned flags,
 				struct page **pagep, void **fsdata)
 <at>  <at>  -308,11 +318,8  <at>  <at>  static int jfs_write_begin(struct file *file, struct address_space *mapping,

 	ret = nobh_write_begin(mapping, pos, len, flags, pagep, fsdata,
 				jfs_get_block);
-	if (unlikely(ret)) {
-		loff_t isize = mapping->host->i_size;
-		if (pos + len > isize)
-			vmtruncate(mapping->host, isize);
-	}
+	if (unlikely(ret))
+		jfs_write_failed(mapping, pos + len);

 	return ret;
 }
 <at>  <at>  -326,6 +333,7  <at>  <at>  static ssize_t jfs_direct_IO(int rw, struct kiocb *iocb,
 	const struct iovec *iov, loff_t offset, unsigned long nr_segs)
 {
 	struct file *file = iocb->ki_filp;
+	struct address_space *mapping = file->f_mapping;
 	struct inode *inode = file->f_mapping->host;
 	ssize_t ret;

 <at>  <at>  -341,7 +349,7  <at>  <at>  static ssize_t jfs_direct_IO(int rw, struct kiocb *iocb,
 		loff_t end = offset + iov_length(iov, nr_segs);

 		if (end > isize)
-			vmtruncate(inode, isize);
+			jfs_write_failed(mapping, end);
 	}

 	return ret;
--

-- 
1.7.3.4

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[PATCH 00/21 v3] drop vmtruncate

Hi all,

I sent the third version of the patch series. After a couple of comments 
by Al and Christoph, now the patches are no more 1:1 replace of 
vmtruncate. A lot of inode_newsize_ok() and truncate_setsize() are now 
gone. For each fs, where needed, I wrote a new fs_write_failed() (as 
suggested by Al watching the ext2 code). The modifications are a bit 
deeper and they are *not* tested. I ask for comments to each fs 
maintainers. I hope the series can be pushed for 3.8.

Changes:
v3: reworked after Al and Christoph comments
v2: add documentation cleaning
v1: first draft

Marco Stornelli (21):
   ufs: drop vmtruncate
   sysv: drop vmtruncate
   reiserfs: drop vmtruncate
   procfs: drop vmtruncate
   omfs: drop vmtruncate
   ocfs2: drop vmtruncate
   adfs: drop vmtruncate
   affs: drop vmtruncate
   bfs: drop vmtruncate
   hfs: drop vmtruncate
   hpfs: drop vmtruncate
   jfs: drop vmtruncate
   hfsplus: drop vmtruncate
   logfs: drop vmtruncate
   minix: drop vmtruncate
   ncpfs: drop vmtruncate
   nilfs2: drop vmtruncate
   ntfs: drop vmtruncate
   vfs: drop vmtruncate
   mm: drop vmtruncate
   Documentation: drop vmtruncate

  Documentation/filesystems/Locking |    6 ------
  Documentation/filesystems/porting |    2 +-
  Documentation/filesystems/vfs.txt |   11 -----------
  fs/adfs/inode.c                   |   15 ++++++++++-----
  fs/affs/file.c                    |   18 ++++++++++++------
  fs/affs/inode.c                   |    5 ++++-
  fs/bfs/file.c                     |   15 ++++++++++-----
  fs/hfs/inode.c                    |   26 ++++++++++++++++++--------
  fs/hfsplus/inode.c                |   27 ++++++++++++++++-----------
  fs/hpfs/file.c                    |   18 ++++++++++++------
  fs/hpfs/inode.c                   |    5 ++++-
  fs/jfs/file.c                     |    6 ++++--
  fs/jfs/inode.c                    |   20 ++++++++++++++------
  fs/libfs.c                        |    2 --
  fs/logfs/readwrite.c              |   10 ++++++++--
  fs/minix/file.c                   |    6 ++++--
  fs/minix/inode.c                  |   17 ++++++++++++-----
  fs/ncpfs/inode.c                  |    4 +---
  fs/nilfs2/file.c                  |    1 -
  fs/nilfs2/inode.c                 |   24 +++++++++++++++---------
  fs/nilfs2/nilfs.h                 |    1 +
  fs/nilfs2/recovery.c              |    3 ++-
  fs/ntfs/file.c                    |   16 +++++++++++++---
  fs/ntfs/inode.c                   |    8 ++++++--
  fs/ntfs/inode.h                   |    4 ++++
  fs/ocfs2/file.c                   |   19 +------------------
  fs/omfs/file.c                    |   22 +++++++++++++++-------
  fs/proc/base.c                    |    3 ++-
  fs/proc/generic.c                 |    3 ++-
  fs/proc/proc_sysctl.c             |    3 ++-
  fs/reiserfs/file.c                |    3 +--
  fs/reiserfs/inode.c               |   15 +++++++++++----
  fs/reiserfs/reiserfs.h            |    1 +
  fs/sysv/file.c                    |    5 +++--
  fs/sysv/itree.c                   |   17 ++++++++++++-----
  fs/ufs/inode.c                    |   15 ++++++++++-----
  include/linux/fs.h                |    1 -
  include/linux/mm.h                |    1 -
  mm/truncate.c                     |   23 -----------------------
  39 files changed, 231 insertions(+), 170 deletions(-)

--

-- 
1.7.3.4
---

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[PATCH] jfs: Fix FITRIM argument handling

Currently when 'range->start' is beyond the end of file system
nothing is done and that fact is ignored, where in fact we should return
EINVAL. The same problem is when 'range.len' is smaller than file system
block.

Fix this by adding check for such conditions and return EINVAL
appropriately.

Signed-off-by: Lukas Czerner <lczerner <at> redhat.com>
---
 fs/jfs/jfs_discard.c |   16 ++++++++++------
 1 files changed, 10 insertions(+), 6 deletions(-)

diff --git a/fs/jfs/jfs_discard.c b/fs/jfs/jfs_discard.c
index 9947563..dfcd503 100644
--- a/fs/jfs/jfs_discard.c
+++ b/fs/jfs/jfs_discard.c
 <at>  <at>  -83,7 +83,7  <at>  <at>  int jfs_ioc_trim(struct inode *ip, struct fstrim_range *range)
 	struct bmap *bmp = JFS_SBI(ip->i_sb)->bmap;
 	struct super_block *sb = ipbmap->i_sb;
 	int agno, agno_end;
-	s64 start, end, minlen;
+	u64 start, end, minlen;
 	u64 trimmed = 0;

 	/**
 <at>  <at>  -93,15 +93,19  <at>  <at>  int jfs_ioc_trim(struct inode *ip, struct fstrim_range *range)
 	 * minlen:	minimum extent length in Bytes
 	 */
 	start = range->start >> sb->s_blocksize_bits;
-	if (start < 0)
-		start = 0;
 	end = start + (range->len >> sb->s_blocksize_bits) - 1;
-	if (end >= bmp->db_mapsize)
-		end = bmp->db_mapsize - 1;
 	minlen = range->minlen >> sb->s_blocksize_bits;
-	if (minlen <= 0)
+	if (minlen == 0)
 		minlen = 1;

+	if (minlen > bmp->db_agsize ||
+	    start >= bmp->db_mapsize ||
+	    range->len < sb->s_blocksize)
+		return -EINVAL;
+
+	if (end >= bmp->db_mapsize)
+		end = bmp->db_mapsize - 1;
+
 	/**
 	 * we trim all ag's within the range
 	 */
--

-- 
1.7.7.6

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finding inodes via block

I have a jfs partition on a linux 2.6.32 install on which 3 sectors recently
became unreadable.  I was able to write zeros to those sectors using dd and
the disk appears to think they're fine and readable again; at least no
sectors are marked reallocated or currently pending by the disk.

  dd of=/dev/sdc if=/dev/zero seek=640 count=1 bs=4096
  dd of=/dev/sdc if=/dev/zero seek=935 count=1 bs=4096
  dd of=/dev/sdc if=/dev/zero seek=1283 count=1 bs=4096

I would like to find out which files on the disk were in those blocks and
thus are now damaged.  Since I have the logical block numbers I assume I 
can get inode numbers from them somehow.

Tried using the 'd' command in jfs_debugfs but am not able to get anything 
that remotely looks correct.  Probably I'm not using a correct offset value, but
I have no idea what I should give it.  Is there a better method?

  Disk /dev/sdc: 3907029168s
  Sector size (logical/physical): 512B/512B
  Partition Table: gpt

  Number  Start  End          Size         File system  Name     Flags
   1      2048s  3907028991s  3907026944s  jfs          primary

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