linux/fs/btrfs
Chris Mason d644d8a1e3 Btrfs: avoid IO stalls behind congested devices in a multi-device FS
The btrfs IO submission threads try to service a bunch of devices with a small
number of threads.  They do a congestion check to try and avoid waiting
on requests for a busy device.

The checks make sure we've sent a few requests down to a given device just so
that we aren't bouncing between busy devices without actually sending down
any IO.  The counter used to decide if we can switch to the next device
is somewhat overloaded.  It is also being used to decide if we've done
a good batch of requests between the WRITE_SYNC or regular priority lists.
It may get reset to zero often, leaving us hammering on a busy device
instead of moving on to another disk.

This commit adds a new counter for the number of bios sent while
servicing a device.  It doesn't get reset or fiddled with.  On
multi-device filesystems, this fixes IO stalls in streaming
write workloads.

Signed-off-by: Chris Mason <chris.mason@oracle.com>
2009-06-10 11:29:49 -04:00
..
acl.c Btrfs: fix acl caching 2009-04-27 13:18:26 -04:00
async-thread.c Btrfs: add a priority queue to the async thread helpers 2009-04-20 15:53:08 -04:00
async-thread.h Btrfs: add a priority queue to the async thread helpers 2009-04-20 15:53:08 -04:00
btrfs_inode.h Btrfs: Mixed back reference (FORWARD ROLLING FORMAT CHANGE) 2009-06-10 11:29:46 -04:00
compat.h Btrfs: drop remaining LINUX_KERNEL_VERSION checks and compat code 2009-01-06 09:38:55 -05:00
compression.c Btrfs: removed unused #include <version.h>'s 2009-01-21 10:49:16 -05:00
compression.h Btrfs: Add zlib compression support 2008-10-29 14:49:59 -04:00
crc32c.h Btrfs: Drop the hardware crc32c asm code 2009-01-07 19:56:59 -05:00
ctree.c Btrfs: balance btree more often 2009-06-10 11:29:47 -04:00
ctree.h Btrfs: Mixed back reference (FORWARD ROLLING FORMAT CHANGE) 2009-06-10 11:29:46 -04:00
delayed-ref.c Btrfs: Mixed back reference (FORWARD ROLLING FORMAT CHANGE) 2009-06-10 11:29:46 -04:00
delayed-ref.h Btrfs: Mixed back reference (FORWARD ROLLING FORMAT CHANGE) 2009-06-10 11:29:46 -04:00
dir-item.c Btrfs: leave btree locks spinning more often 2009-03-24 16:14:28 -04:00
disk-io.c Btrfs: fix metadata dirty throttling limits 2009-06-10 11:29:48 -04:00
disk-io.h Btrfs: leave btree locks spinning more often 2009-03-24 16:14:28 -04:00
export.c Btrfs: Mixed back reference (FORWARD ROLLING FORMAT CHANGE) 2009-06-10 11:29:46 -04:00
export.h NFS support for btrfs - v3 2008-09-25 11:04:06 -04:00
extent_io.c btrfs: Fix set/clear_extent_bit for 'end == (u64)-1' 2009-06-10 11:29:46 -04:00
extent_io.h Btrfs: leave btree locks spinning more often 2009-03-24 16:14:28 -04:00
extent_map.c Btrfs: kill btrfs_cache_create 2009-04-24 15:46:04 -04:00
extent_map.h Btrfs: Fix csum error for compressed data 2008-11-10 07:34:43 -05:00
extent-tree.c Btrfs: Mixed back reference (FORWARD ROLLING FORMAT CHANGE) 2009-06-10 11:29:46 -04:00
file-item.c Btrfs: leave btree locks spinning more often 2009-03-24 16:14:28 -04:00
file.c Btrfs: Mixed back reference (FORWARD ROLLING FORMAT CHANGE) 2009-06-10 11:29:46 -04:00
free-space-cache.c Btrfs: reduce mount -o ssd CPU usage 2009-06-10 11:29:48 -04:00
free-space-cache.h Btrfs: rework allocation clustering 2009-04-03 09:47:43 -04:00
hash.h Switch btrfs_name_hash() to crc32c 2008-09-25 11:04:06 -04:00
inode-item.c Btrfs: leave btree locks spinning more often 2009-03-24 16:14:28 -04:00
inode-map.c Btrfs: Fix a trivial warning using max() of u64 vs ULL. 2009-04-27 08:37:49 -04:00
inode.c Btrfs: Mixed back reference (FORWARD ROLLING FORMAT CHANGE) 2009-06-10 11:29:46 -04:00
ioctl.c Btrfs: Mixed back reference (FORWARD ROLLING FORMAT CHANGE) 2009-06-10 11:29:46 -04:00
ioctl.h Btrfs: fix ioctl arg size (userland incompatible change!) 2009-01-16 11:59:08 -05:00
Kconfig Btrfs: make btrfs acls selectable 2009-02-04 09:28:28 -05:00
locking.c Btrfs: fix typos in comments 2009-04-02 16:46:06 -04:00
locking.h Btrfs: fix spinlock assertions on UP systems 2009-03-09 11:45:38 -04:00
Makefile Btrfs: Mixed back reference (FORWARD ROLLING FORMAT CHANGE) 2009-06-10 11:29:46 -04:00
ordered-data.c Btrfs: use WRITE_SYNC for synchronous writes 2009-04-20 15:53:08 -04:00
ordered-data.h Btrfs: add extra flushing for renames and truncates 2009-03-31 14:27:58 -04:00
orphan.c Btrfs: Create orphan inode records to prevent lost files after a crash 2008-09-25 11:04:05 -04:00
print-tree.c Btrfs: Mixed back reference (FORWARD ROLLING FORMAT CHANGE) 2009-06-10 11:29:46 -04:00
print-tree.h Btrfs: Create extent_buffer interface for large blocksizes 2008-09-25 11:03:56 -04:00
ref-cache.c Btrfs: Make btrfs_drop_snapshot work in larger and more efficient chunks 2009-02-04 09:27:02 -05:00
ref-cache.h Btrfs: Make btrfs_drop_snapshot work in larger and more efficient chunks 2009-02-04 09:27:02 -05:00
relocation.c Btrfs: Mixed back reference (FORWARD ROLLING FORMAT CHANGE) 2009-06-10 11:29:46 -04:00
root-tree.c Btrfs: Mixed back reference (FORWARD ROLLING FORMAT CHANGE) 2009-06-10 11:29:46 -04:00
struct-funcs.c Btrfs: Fix checkpatch.pl warnings 2009-01-05 21:25:51 -05:00
super.c Btrfs: Mixed back reference (FORWARD ROLLING FORMAT CHANGE) 2009-06-10 11:29:46 -04:00
sysfs.c Btrfs: Fix checkpatch.pl warnings 2009-01-05 21:25:51 -05:00
transaction.c Btrfs: Mixed back reference (FORWARD ROLLING FORMAT CHANGE) 2009-06-10 11:29:46 -04:00
transaction.h Btrfs: Mixed back reference (FORWARD ROLLING FORMAT CHANGE) 2009-06-10 11:29:46 -04:00
tree-defrag.c Btrfs: do extent allocation and reference count updates in the background 2009-03-24 16:14:25 -04:00
tree-log.c Btrfs: Mixed back reference (FORWARD ROLLING FORMAT CHANGE) 2009-06-10 11:29:46 -04:00
tree-log.h Btrfs: tree logging unlink/rename fixes 2009-03-24 16:14:52 -04:00
version.h Update Btrfs files for in-kernel usage 2008-09-25 15:41:59 -04:00
version.sh Btrfs: Fixes for 2.6.28-rc API changes 2008-11-19 21:17:22 -05:00
volumes.c Btrfs: avoid IO stalls behind congested devices in a multi-device FS 2009-06-10 11:29:49 -04:00
volumes.h Btrfs: When shrinking, only update disk size on success 2009-04-27 07:40:51 -04:00
xattr.c Btrfs: selinux support 2009-02-04 09:29:13 -05:00
xattr.h Btrfs: selinux support 2009-02-04 09:29:13 -05:00
zlib.c Btrfs: Fix checkpatch.pl warnings 2009-01-05 21:25:51 -05:00