Commit Graph

26 Commits

Author SHA1 Message Date
David Chinner 92821e2ba4 [XFS] Lazy Superblock Counters
When we have a couple of hundred transactions on the fly at once, they all
typically modify the on disk superblock in some way.
create/unclink/mkdir/rmdir modify inode counts, allocation/freeing modify
free block counts.

When these counts are modified in a transaction, they must eventually lock
the superblock buffer and apply the mods. The buffer then remains locked
until the transaction is committed into the incore log buffer. The result
of this is that with enough transactions on the fly the incore superblock
buffer becomes a bottleneck.

The result of contention on the incore superblock buffer is that
transaction rates fall - the more pressure that is put on the superblock
buffer, the slower things go.

The key to removing the contention is to not require the superblock fields
in question to be locked. We do that by not marking the superblock dirty
in the transaction. IOWs, we modify the incore superblock but do not
modify the cached superblock buffer. In short, we do not log superblock
modifications to critical fields in the superblock on every transaction.
In fact we only do it just before we write the superblock to disk every
sync period or just before unmount.

This creates an interesting problem - if we don't log or write out the
fields in every transaction, then how do the values get recovered after a
crash? the answer is simple - we keep enough duplicate, logged information
in other structures that we can reconstruct the correct count after log
recovery has been performed.

It is the AGF and AGI structures that contain the duplicate information;
after recovery, we walk every AGI and AGF and sum their individual
counters to get the correct value, and we do a transaction into the log to
correct them. An optimisation of this is that if we have a clean unmount
record, we know the value in the superblock is correct, so we can avoid
the summation walk under normal conditions and so mount/recovery times do
not change under normal operation.

One wrinkle that was discovered during development was that the blocks
used in the freespace btrees are never accounted for in the AGF counters.
This was once a valid optimisation to make; when the filesystem is full,
the free space btrees are empty and consume no space. Hence when it
matters, the "accounting" is correct. But that means the when we do the
AGF summations, we would not have a correct count and xfs_check would
complain. Hence a new counter was added to track the number of blocks used
by the free space btrees. This is an *on-disk format change*.

As a result of this, lazy superblock counters are a mkfs option and at the
moment on linux there is no way to convert an old filesystem. This is
possible - xfs_db can be used to twiddle the right bits and then
xfs_repair will do the format conversion for you. Similarly, you can
convert backwards as well. At some point we'll add functionality to
xfs_admin to do the bit twiddling easily....

SGI-PV: 964999
SGI-Modid: xfs-linux-melb:xfs-kern:28652a

Signed-off-by: David Chinner <dgc@sgi.com>
Signed-off-by: Christoph Hellwig <hch@infradead.org>
Signed-off-by: Tim Shimmin <tes@sgi.com>
2007-07-14 15:28:50 +10:00
Utako Kusaka 3a02ee1828 [XFS] Get rid of redundant "required" in msg.
SGI-PV: 963466
SGI-Modid: xfs-linux-melb:xfs-kern:28416a

Signed-off-by: Utako Kusaka <utako@tnes.nec.co.jp>
Signed-off-by: Tim Shimmin <tes@sgi.com>
Signed-off-by: Christoph Hellwig <hch@infradead.org>
2007-05-08 13:50:06 +10:00
Eric Sandeen e9ed9d2240 [XFS] remove more misc. unused args
Patch provided by Eric Sandeen.

SGI-PV: 961695
SGI-Modid: xfs-linux-melb:xfs-kern:28205a

Signed-off-by: Eric Sandeen <sandeen@sandeen.net>
Signed-off-by: Lachlan McIlroy <lachlan@sgi.com>
Signed-off-by: Tim Shimmin <tes@sgi.com>
2007-05-08 13:48:56 +10:00
Eric Sandeen 1c72bf9003 [XFS] The last argument "lsn" of xfs_trans_commit() is always called with
NULL.

Patch provided by Eric Sandeen.

SGI-PV: 961693
SGI-Modid: xfs-linux-melb:xfs-kern:28199a

Signed-off-by: Eric Sandeen <sandeen@sandeen.net>
Signed-off-by: Lachlan McIlroy <lachlan@sgi.com>
Signed-off-by: Tim Shimmin <tes@sgi.com>
2007-05-08 13:48:42 +10:00
Lachlan McIlroy 5478eead85 [XFS] Re-initialize the per-cpu superblock counters after recovery.
After filesystem recovery the superblock is re-read to bring in any
changes. If the per-cpu superblock counters are not re-initialized from
the superblock then the next time the per-cpu counters are disabled they
might overwrite the global counter with a bogus value.

SGI-PV: 957348
SGI-Modid: xfs-linux-melb:xfs-kern:27999a

Signed-off-by: Lachlan McIlroy <lachlan@sgi.com>
Signed-off-by: David Chinner <dgc@sgi.com>
Signed-off-by: Tim Shimmin <tes@sgi.com>
2007-02-10 18:36:29 +11:00
Eric Sandeen 804195b63a [XFS] Get rid of old 5.3/6.1 v1 log items. Cleanup patch sent in by Eric
Sandeen.

SGI-PV: 958736
SGI-Modid: xfs-linux-melb:xfs-kern:27596a

Signed-off-by: Eric Sandeen <sandeen@sandeen.net>
Signed-off-by: Tim Shimmin <tes@sgi.com>
2007-02-10 18:35:02 +11:00
Nathan Scott 6fdf8ccc09 [XFS] Rework code snippets slightly to remove remaining recent-gcc
warnings.

SGI-PV: 904196
SGI-Modid: xfs-linux-melb:xfs-kern:26364a

Signed-off-by: Nathan Scott <nathans@sgi.com>
2006-06-28 10:13:52 +10:00
Nathan Scott f6c2d1fa63 [XFS] Remove version 1 directory code. Never functioned on Linux, just
pure bloat.

SGI-PV: 952969
SGI-Modid: xfs-linux-melb:xfs-kern:26251a

Signed-off-by: Nathan Scott <nathans@sgi.com>
2006-06-20 13:04:51 +10:00
Nathan Scott b65745205f [XFS] Portability changes: remove prdev, stick to one diagnostic
interface.

SGI-PV: 953338
SGI-Modid: xfs-linux-melb:xfs-kern:26103a

Signed-off-by: Nathan Scott <nathans@sgi.com>
2006-06-09 15:29:40 +10:00
Nathan Scott 7d04a335b6 [XFS] Shutdown the filesystem if all device paths have gone. Made
shutdown vop flags consistent with sync vop flags declarations too.

SGI-PV: 939911
SGI-Modid: xfs-linux-melb:xfs-kern:26096a

Signed-off-by: Nathan Scott <nathans@sgi.com>
2006-06-09 14:58:38 +10:00
Tim Shimmin 87c199c2a7 [XFS] Over zealous with doing endian conversions. We endian converted the
logged version of di_next_unlinked which is actually always stored in the
correct ondisk format. This was pointed out to us by Shailendra Tripathi.
And is evident in the xfs qa test of 121.

SGI-PV: 953263
SGI-Modid: xfs-linux-melb:xfs-kern:26044a

Signed-off-by: Tim Shimmin <tes@sgi.com>
Signed-off-by: Nathan Scott <nathans@sgi.com>
2006-06-09 14:56:16 +10:00
Tim Shimmin 6d192a9b82 [XFS] inode items and EFI/EFDs have different ondisk format for 32bit and
64bit kernels allow recovery to handle both versions and do the necessary
decoding

SGI-PV: 952214
SGI-Modid: xfs-linux-melb:xfs-kern:26011a

Signed-off-by: Tim Shimmin <tes@sgi.com>
Signed-off-by: Nathan Scott <nathans@sgi.com>
2006-06-09 14:55:38 +10:00
Nathan Scott c41564b5af [XFS] We really suck at spulling. Thanks to Chris Pascoe for fixing all
these typos.

SGI-PV: 904196
SGI-Modid: xfs-linux-melb:xfs-kern:25539a

Signed-off-by: Nathan Scott <nathans@sgi.com>
2006-03-29 08:55:14 +10:00
Nathan Scott b12dd34298 [XFS] Fix an infinite loop issue in bulkstat when a corrupt inode is
detected.  Thanks to Roger Willcocks.

SGI-PV: 951054
SGI-Modid: xfs-linux-melb:xfs-kern:25477a

Signed-off-by: Nathan Scott <nathans@sgi.com>
2006-03-17 17:26:04 +11:00
Nathan Scott 77a7cce425 [XFS] Fix quotaoff logitem for project quota, affects log recovery only.
SGI-PV: 946444
SGI-Modid: xfs-linux-melb:xfs-kern:24768a

Signed-off-by: Nathan Scott <nathans@sgi.com>
2006-01-11 15:35:57 +11:00
Eric Sandeen 65be605419 [XFS] remove unused "readonly" arg from xlog_find_tail and xlog_recover
SGI-PV: 946611
SGI-Modid: xfs-linux-melb:xfs-kern:203307a

Signed-off-by: Eric Sandeen <sandeen@sgi.com>
Signed-off-by: Nathan Scott <nathans@sgi.com>
2006-01-11 15:34:19 +11:00
Christoph Hellwig 16259e7d95 [XFS] Endianess annotations for various allocator data structures
SGI-PV: 943272
SGI-Modid: xfs-linux:xfs-kern:201006a

Signed-off-by: Christoph Hellwig <hch@sgi.com>
Signed-off-by: Nathan Scott <nathans@sgi.com>
2005-11-02 15:11:25 +11:00
Christoph Hellwig 1149d96ae8 [XFS] endianess annotations and cleanup for the quota code
SGI-PV: 943272
SGI-Modid: xfs-linux:xfs-kern:199767a

Signed-off-by: Christoph Hellwig <hch@sgi.com>
Signed-off-by: Nathan Scott <nathans@sgi.com>
2005-11-02 15:01:12 +11:00
Nathan Scott 7b71876980 [XFS] Update license/copyright notices to match the prefered SGI
boilerplate.

SGI-PV: 913862
SGI-Modid: xfs-linux:xfs-kern:23903a

Signed-off-by: Nathan Scott <nathans@sgi.com>
2005-11-02 14:58:39 +11:00
Nathan Scott a844f4510d [XFS] Remove xfs_macros.c, xfs_macros.h, rework headers a whole lot.
SGI-PV: 943122
SGI-Modid: xfs-linux:xfs-kern:23901a

Signed-off-by: Nathan Scott <nathans@sgi.com>
2005-11-02 14:38:42 +11:00
Nathan Scott fc1f8c1ca3 [XFS] Track external log/realtime device names for correct reporting in
/proc/mounts.

SGI-PV: 942984
SGI-Modid: xfs-linux:xfs-kern:23862a

Signed-off-by: Nathan Scott <nathans@sgi.com>
2005-11-02 11:44:33 +11:00
Christoph Hellwig 760dea671e [XFS] Fix sparse warnings in kmem_* functions Patch from Victor Fusco
<victor@cetuc.puc-rio.br>

SGI-PV: 940376
SGI-Modid: xfs-linux:xfs-kern:196705a

Signed-off-by: Christoph Hellwig <hch@sgi.com>
Signed-off-by: Nathan Scott <nathans@sgi.com>
2005-09-02 16:56:02 +10:00
Christoph Hellwig 7d795ca344 [XFS] consolidate extent item freeing
SGI-PV: 938062
SGI-Modid: xfs-linux:xfs-kern:194415a

Signed-off-by: Christoph Hellwig <hch@sgi.com>
Signed-off-by: Nathan Scott <nathans@sgi.com>
2005-06-21 15:41:19 +10:00
Nathan Scott c8ad20ffeb [XFS] Add support for project quota, based on Dan Knappes earlier work.
SGI-PV: 932952
SGI-Modid: xfs-linux:xfs-kern:22805a

Signed-off-by: Nathan Scott <nathans@sgi.com>
2005-06-21 15:38:48 +10:00
Christoph Hellwig ba0f32d460 [XFS] mark various symbols static Patch from Adrian Bunk
SGI-PV: 936255
SGI-Modid: xfs-linux:xfs-kern:192760a

Signed-off-by: Christoph Hellwig <hch@sgi.com>
Signed-off-by: Nathan Scott <nathans@sgi.com>
2005-06-21 15:36:52 +10:00
Linus Torvalds 1da177e4c3 Linux-2.6.12-rc2
Initial git repository build. I'm not bothering with the full history,
even though we have it. We can create a separate "historical" git
archive of that later if we want to, and in the meantime it's about
3.2GB when imported into git - space that would just make the early
git days unnecessarily complicated, when we don't have a lot of good
infrastructure for it.

Let it rip!
2005-04-16 15:20:36 -07:00