Josef Bacik
2011-Jul-15 18:29 UTC
[PATCH] Btrfs: don''t be as agressive with delalloc metadata reservations
Currently we reserve enough space to COW an entirely full btree for every extent
we have reserved for an inode. This _sucks_, because you only need to COW once,
and then everybody else is ok. Unfortunately we don''t know
we''ll all be able to
get into the same transaction so that''s what we have had to do. But
the global
reserve holds a reservation large enough to cover a large percentage of all the
metadata currently in the fs. So all we really need to account for is any new
blocks that we may allocate. So fix this by
1) Passing to btrfs_alloc_free_block() wether this is a new block or a COW
block. If it is a COW block we use the global reserve, if not we use the
trans->block_rsv.
2) Reduce the amount of space we reserve. Since we don''t need to
account for
cow''ing the tree we can just keep track of new blocks to reserve, which
greatly
reduces the reservation amount.
This makes my basic random write test go from 3 mb/s to 75 mb/s. I''ve
tested
this with my horrible ENOSPC test and it seems to work out fine. Thanks,
Signed-off-by: Josef Bacik <josef@redhat.com>
---
fs/btrfs/ctree.c | 10 +++++-----
fs/btrfs/ctree.h | 5 ++---
fs/btrfs/disk-io.c | 3 ++-
fs/btrfs/extent-tree.c | 20 +++++++++++++++-----
fs/btrfs/ioctl.c | 2 +-
5 files changed, 25 insertions(+), 15 deletions(-)
diff --git a/fs/btrfs/ctree.c b/fs/btrfs/ctree.c
index 2e66786..fbd48e9 100644
--- a/fs/btrfs/ctree.c
+++ b/fs/btrfs/ctree.c
@@ -206,7 +206,7 @@ int btrfs_copy_root(struct btrfs_trans_handle *trans,
cow = btrfs_alloc_free_block(trans, root, buf->len, 0,
new_root_objectid, &disk_key, level,
- buf->start, 0);
+ buf->start, 0, 1);
if (IS_ERR(cow))
return PTR_ERR(cow);
@@ -412,7 +412,7 @@ static noinline int __btrfs_cow_block(struct
btrfs_trans_handle *trans,
cow = btrfs_alloc_free_block(trans, root, buf->len, parent_start,
root->root_key.objectid, &disk_key,
- level, search_start, empty_size);
+ level, search_start, empty_size, 0);
if (IS_ERR(cow))
return PTR_ERR(cow);
@@ -1985,7 +1985,7 @@ static noinline int insert_new_root(struct
btrfs_trans_handle *trans,
c = btrfs_alloc_free_block(trans, root, root->nodesize, 0,
root->root_key.objectid, &lower_key,
- level, root->node->start, 0);
+ level, root->node->start, 0, 1);
if (IS_ERR(c))
return PTR_ERR(c);
@@ -2112,7 +2112,7 @@ static noinline int split_node(struct btrfs_trans_handle
*trans,
split = btrfs_alloc_free_block(trans, root, root->nodesize, 0,
root->root_key.objectid,
- &disk_key, level, c->start, 0);
+ &disk_key, level, c->start, 0, 1);
if (IS_ERR(split))
return PTR_ERR(split);
@@ -2937,7 +2937,7 @@ again:
right = btrfs_alloc_free_block(trans, root, root->leafsize, 0,
root->root_key.objectid,
- &disk_key, 0, l->start, 0);
+ &disk_key, 0, l->start, 0, 1);
if (IS_ERR(right))
return PTR_ERR(right);
diff --git a/fs/btrfs/ctree.h b/fs/btrfs/ctree.h
index 3ba4d5f..1accb56 100644
--- a/fs/btrfs/ctree.h
+++ b/fs/btrfs/ctree.h
@@ -2135,8 +2135,7 @@ static inline bool btrfs_mixed_space_info(struct
btrfs_space_info *space_info)
static inline u64 btrfs_calc_trans_metadata_size(struct btrfs_root *root,
unsigned num_items)
{
- return (root->leafsize + root->nodesize * (BTRFS_MAX_LEVEL - 1)) *
- 3 * num_items;
+ return root->leafsize * 3 * num_items;
}
void btrfs_put_block_group(struct btrfs_block_group_cache *cache);
@@ -2161,7 +2160,7 @@ struct extent_buffer *btrfs_alloc_free_block(struct
btrfs_trans_handle *trans,
struct btrfs_root *root, u32 blocksize,
u64 parent, u64 root_objectid,
struct btrfs_disk_key *key, int level,
- u64 hint, u64 empty_size);
+ u64 hint, u64 empty_size, int new_block);
void btrfs_free_tree_block(struct btrfs_trans_handle *trans,
struct btrfs_root *root,
struct extent_buffer *buf,
diff --git a/fs/btrfs/disk-io.c b/fs/btrfs/disk-io.c
index 234a084..0245cad 100644
--- a/fs/btrfs/disk-io.c
+++ b/fs/btrfs/disk-io.c
@@ -1143,7 +1143,8 @@ static struct btrfs_root *alloc_log_tree(struct
btrfs_trans_handle *trans,
root->ref_cows = 0;
leaf = btrfs_alloc_free_block(trans, root, root->leafsize, 0,
- BTRFS_TREE_LOG_OBJECTID, NULL, 0, 0, 0);
+ BTRFS_TREE_LOG_OBJECTID, NULL, 0, 0, 0,
+ 1);
if (IS_ERR(leaf)) {
kfree(root);
return ERR_CAST(leaf);
diff --git a/fs/btrfs/extent-tree.c b/fs/btrfs/extent-tree.c
index 2e0f87b..e2dd833 100644
--- a/fs/btrfs/extent-tree.c
+++ b/fs/btrfs/extent-tree.c
@@ -5661,13 +5661,23 @@ struct extent_buffer *btrfs_init_new_buffer(struct
btrfs_trans_handle *trans,
static struct btrfs_block_rsv *
use_block_rsv(struct btrfs_trans_handle *trans,
- struct btrfs_root *root, u32 blocksize)
+ struct btrfs_root *root, u32 blocksize, int new_block)
{
- struct btrfs_block_rsv *block_rsv;
+ struct btrfs_block_rsv *block_rsv = NULL;
struct btrfs_block_rsv *global_rsv =
&root->fs_info->global_block_rsv;
int ret;
- block_rsv = get_block_rsv(trans, root);
+ if (root->ref_cows) {
+ if (new_block)
+ block_rsv = trans->block_rsv;
+ else
+ block_rsv = global_rsv;
+ } else {
+ block_rsv = root->block_rsv;
+ }
+
+ if (!block_rsv)
+ block_rsv = &root->fs_info->empty_block_rsv;
if (block_rsv->size == 0) {
ret = reserve_metadata_bytes(trans, root, block_rsv,
@@ -5726,7 +5736,7 @@ struct extent_buffer *btrfs_alloc_free_block(struct
btrfs_trans_handle *trans,
struct btrfs_root *root, u32 blocksize,
u64 parent, u64 root_objectid,
struct btrfs_disk_key *key, int level,
- u64 hint, u64 empty_size)
+ u64 hint, u64 empty_size, int new_block)
{
struct btrfs_key ins;
struct btrfs_block_rsv *block_rsv;
@@ -5735,7 +5745,7 @@ struct extent_buffer *btrfs_alloc_free_block(struct
btrfs_trans_handle *trans,
int ret;
- block_rsv = use_block_rsv(trans, root, blocksize);
+ block_rsv = use_block_rsv(trans, root, blocksize, new_block);
if (IS_ERR(block_rsv))
return ERR_CAST(block_rsv);
diff --git a/fs/btrfs/ioctl.c b/fs/btrfs/ioctl.c
index fd252ff..39fb634 100644
--- a/fs/btrfs/ioctl.c
+++ b/fs/btrfs/ioctl.c
@@ -352,7 +352,7 @@ static noinline int create_subvol(struct btrfs_root *root,
}
leaf = btrfs_alloc_free_block(trans, root, root->leafsize,
- 0, objectid, NULL, 0, 0, 0);
+ 0, objectid, NULL, 0, 0, 0, 1);
if (IS_ERR(leaf)) {
ret = PTR_ERR(leaf);
goto fail;
--
1.7.5.2
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liubo
2011-Jul-18 03:04 UTC
Re: [PATCH] Btrfs: don''t be as agressive with delalloc metadata reservations
On 07/16/2011 02:29 AM, Josef Bacik wrote:> Currently we reserve enough space to COW an entirely full btree for every extent > we have reserved for an inode. This _sucks_, because you only need to COW once, > and then everybody else is ok. Unfortunately we don''t know we''ll all be able to > get into the same transaction so that''s what we have had to do. But the global > reserve holds a reservation large enough to cover a large percentage of all the > metadata currently in the fs. So all we really need to account for is any new > blocks that we may allocate. So fix this by > > 1) Passing to btrfs_alloc_free_block() wether this is a new block or a COW > block. If it is a COW block we use the global reserve, if not we use the > trans->block_rsv. > 2) Reduce the amount of space we reserve. Since we don''t need to account for > cow''ing the tree we can just keep track of new blocks to reserve, which greatly > reduces the reservation amount. > > This makes my basic random write test go from 3 mb/s to 75 mb/s. I''ve tested > this with my horrible ENOSPC test and it seems to work out fine. Thanks, >Hi, Josef, After I patched this and did a "tar xf source.tar", I got lots of warnings, Would you like to look into this? ------------[ cut here ]------------ WARNING: at fs/btrfs/extent-tree.c:5695 btrfs_alloc_free_block+0x178/0x340 [btrfs]() Hardware name: QiTianM7150 Modules linked in: btrfs iptable_nat nf_nat zlib_deflate libcrc32c ebtable_nat ebtables bridge stp llc cpufreq_ondemand acpi_cpufreq freq_table mperf be2iscsi iscsi_boot_sysfs bnx2i cnic uio cxgb3i libcxgbi cxgb3 mdio iscsi_tcp libiscsi_tcp libiscsi scsi_transport_iscsi ext3 jbd dm_mirror dm_region_hash dm_log dm_mod sg ppdev serio_raw pcspkr i2c_i801 iTCO_wdt iTCO_vendor_support sky2 parport_pc parport ext4 mbcache jbd2 sd_mod crc_t10dif pata_acpi ata_generic ata_piix i915 drm_kms_helper drm i2c_algo_bit i2c_core video [last unloaded: btrfs] Pid: 16008, comm: umount Tainted: G W 2.6.39+ #9 Call Trace: [<ffffffff81053baf>] warn_slowpath_common+0x7f/0xc0 [<ffffffff81053c0a>] warn_slowpath_null+0x1a/0x20 [<ffffffffa04d37d8>] btrfs_alloc_free_block+0x178/0x340 [btrfs] [<ffffffffa0501768>] ? read_extent_buffer+0xd8/0x1d0 [btrfs] [<ffffffffa04be625>] __btrfs_cow_block+0x155/0x5f0 [btrfs] [<ffffffffa04bebcb>] btrfs_cow_block+0x10b/0x240 [btrfs] [<ffffffffa04c4c8e>] btrfs_search_slot+0x49e/0x7a0 [btrfs] [<ffffffffa04d2399>] btrfs_write_dirty_block_groups+0x1a9/0x4d0 [btrfs] [<ffffffffa0512e20>] ? btrfs_tree_unlock+0x50/0x50 [btrfs] [<ffffffffa04df845>] commit_cowonly_roots+0x105/0x1e0 [btrfs] [<ffffffffa04e0708>] btrfs_commit_transaction+0x428/0x850 [btrfs] [<ffffffffa04df9b8>] ? wait_current_trans+0x28/0x100 [btrfs] [<ffffffffa04e0c25>] ? join_transaction+0x25/0x250 [btrfs] [<ffffffff81075590>] ? wake_up_bit+0x40/0x40 [<ffffffffa04bb187>] btrfs_sync_fs+0x67/0xd0 [btrfs] [<ffffffff8116c27e>] __sync_filesystem+0x5e/0x90 [<ffffffff8116c38b>] sync_filesystem+0x4b/0x70 [<ffffffff811441c4>] generic_shutdown_super+0x34/0xf0 [<ffffffff81144316>] kill_anon_super+0x16/0x60 [<ffffffff81144a25>] deactivate_locked_super+0x45/0x70 [<ffffffff8114568a>] deactivate_super+0x4a/0x70 [<ffffffff8115efdc>] mntput_no_expire+0x13c/0x1c0 [<ffffffff8115f7bb>] sys_umount+0x7b/0x3a0 [<ffffffff81466b2b>] system_call_fastpath+0x16/0x1b ---[ end trace 9a65800674b03b84 ]--- thanks, liubo> Signed-off-by: Josef Bacik <josef@redhat.com> > --- > fs/btrfs/ctree.c | 10 +++++----- > fs/btrfs/ctree.h | 5 ++--- > fs/btrfs/disk-io.c | 3 ++- > fs/btrfs/extent-tree.c | 20 +++++++++++++++----- > fs/btrfs/ioctl.c | 2 +- > 5 files changed, 25 insertions(+), 15 deletions(-) > > diff --git a/fs/btrfs/ctree.c b/fs/btrfs/ctree.c > index 2e66786..fbd48e9 100644 > --- a/fs/btrfs/ctree.c > +++ b/fs/btrfs/ctree.c > @@ -206,7 +206,7 @@ int btrfs_copy_root(struct btrfs_trans_handle *trans, > > cow = btrfs_alloc_free_block(trans, root, buf->len, 0, > new_root_objectid, &disk_key, level, > - buf->start, 0); > + buf->start, 0, 1); > if (IS_ERR(cow)) > return PTR_ERR(cow); > > @@ -412,7 +412,7 @@ static noinline int __btrfs_cow_block(struct btrfs_trans_handle *trans, > > cow = btrfs_alloc_free_block(trans, root, buf->len, parent_start, > root->root_key.objectid, &disk_key, > - level, search_start, empty_size); > + level, search_start, empty_size, 0); > if (IS_ERR(cow)) > return PTR_ERR(cow); > > @@ -1985,7 +1985,7 @@ static noinline int insert_new_root(struct btrfs_trans_handle *trans, > > c = btrfs_alloc_free_block(trans, root, root->nodesize, 0, > root->root_key.objectid, &lower_key, > - level, root->node->start, 0); > + level, root->node->start, 0, 1); > if (IS_ERR(c)) > return PTR_ERR(c); > > @@ -2112,7 +2112,7 @@ static noinline int split_node(struct btrfs_trans_handle *trans, > > split = btrfs_alloc_free_block(trans, root, root->nodesize, 0, > root->root_key.objectid, > - &disk_key, level, c->start, 0); > + &disk_key, level, c->start, 0, 1); > if (IS_ERR(split)) > return PTR_ERR(split); > > @@ -2937,7 +2937,7 @@ again: > > right = btrfs_alloc_free_block(trans, root, root->leafsize, 0, > root->root_key.objectid, > - &disk_key, 0, l->start, 0); > + &disk_key, 0, l->start, 0, 1); > if (IS_ERR(right)) > return PTR_ERR(right); > > diff --git a/fs/btrfs/ctree.h b/fs/btrfs/ctree.h > index 3ba4d5f..1accb56 100644 > --- a/fs/btrfs/ctree.h > +++ b/fs/btrfs/ctree.h > @@ -2135,8 +2135,7 @@ static inline bool btrfs_mixed_space_info(struct btrfs_space_info *space_info) > static inline u64 btrfs_calc_trans_metadata_size(struct btrfs_root *root, > unsigned num_items) > { > - return (root->leafsize + root->nodesize * (BTRFS_MAX_LEVEL - 1)) * > - 3 * num_items; > + return root->leafsize * 3 * num_items; > } > > void btrfs_put_block_group(struct btrfs_block_group_cache *cache); > @@ -2161,7 +2160,7 @@ struct extent_buffer *btrfs_alloc_free_block(struct btrfs_trans_handle *trans, > struct btrfs_root *root, u32 blocksize, > u64 parent, u64 root_objectid, > struct btrfs_disk_key *key, int level, > - u64 hint, u64 empty_size); > + u64 hint, u64 empty_size, int new_block); > void btrfs_free_tree_block(struct btrfs_trans_handle *trans, > struct btrfs_root *root, > struct extent_buffer *buf, > diff --git a/fs/btrfs/disk-io.c b/fs/btrfs/disk-io.c > index 234a084..0245cad 100644 > --- a/fs/btrfs/disk-io.c > +++ b/fs/btrfs/disk-io.c > @@ -1143,7 +1143,8 @@ static struct btrfs_root *alloc_log_tree(struct btrfs_trans_handle *trans, > root->ref_cows = 0; > > leaf = btrfs_alloc_free_block(trans, root, root->leafsize, 0, > - BTRFS_TREE_LOG_OBJECTID, NULL, 0, 0, 0); > + BTRFS_TREE_LOG_OBJECTID, NULL, 0, 0, 0, > + 1); > if (IS_ERR(leaf)) { > kfree(root); > return ERR_CAST(leaf); > diff --git a/fs/btrfs/extent-tree.c b/fs/btrfs/extent-tree.c > index 2e0f87b..e2dd833 100644 > --- a/fs/btrfs/extent-tree.c > +++ b/fs/btrfs/extent-tree.c > @@ -5661,13 +5661,23 @@ struct extent_buffer *btrfs_init_new_buffer(struct btrfs_trans_handle *trans, > > static struct btrfs_block_rsv * > use_block_rsv(struct btrfs_trans_handle *trans, > - struct btrfs_root *root, u32 blocksize) > + struct btrfs_root *root, u32 blocksize, int new_block) > { > - struct btrfs_block_rsv *block_rsv; > + struct btrfs_block_rsv *block_rsv = NULL; > struct btrfs_block_rsv *global_rsv = &root->fs_info->global_block_rsv; > int ret; > > - block_rsv = get_block_rsv(trans, root); > + if (root->ref_cows) { > + if (new_block) > + block_rsv = trans->block_rsv; > + else > + block_rsv = global_rsv; > + } else { > + block_rsv = root->block_rsv; > + } > + > + if (!block_rsv) > + block_rsv = &root->fs_info->empty_block_rsv; > > if (block_rsv->size == 0) { > ret = reserve_metadata_bytes(trans, root, block_rsv, > @@ -5726,7 +5736,7 @@ struct extent_buffer *btrfs_alloc_free_block(struct btrfs_trans_handle *trans, > struct btrfs_root *root, u32 blocksize, > u64 parent, u64 root_objectid, > struct btrfs_disk_key *key, int level, > - u64 hint, u64 empty_size) > + u64 hint, u64 empty_size, int new_block) > { > struct btrfs_key ins; > struct btrfs_block_rsv *block_rsv; > @@ -5735,7 +5745,7 @@ struct extent_buffer *btrfs_alloc_free_block(struct btrfs_trans_handle *trans, > int ret; > > > - block_rsv = use_block_rsv(trans, root, blocksize); > + block_rsv = use_block_rsv(trans, root, blocksize, new_block); > if (IS_ERR(block_rsv)) > return ERR_CAST(block_rsv); > > diff --git a/fs/btrfs/ioctl.c b/fs/btrfs/ioctl.c > index fd252ff..39fb634 100644 > --- a/fs/btrfs/ioctl.c > +++ b/fs/btrfs/ioctl.c > @@ -352,7 +352,7 @@ static noinline int create_subvol(struct btrfs_root *root, > } > > leaf = btrfs_alloc_free_block(trans, root, root->leafsize, > - 0, objectid, NULL, 0, 0, 0); > + 0, objectid, NULL, 0, 0, 0, 1); > if (IS_ERR(leaf)) { > ret = PTR_ERR(leaf); > goto fail;-- To unsubscribe from this list: send the line "unsubscribe linux-btrfs" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
Josef Bacik
2011-Jul-18 13:33 UTC
Re: [PATCH] Btrfs: don''t be as agressive with delalloc metadata reservations
On 07/17/2011 11:04 PM, liubo wrote:> On 07/16/2011 02:29 AM, Josef Bacik wrote: >> Currently we reserve enough space to COW an entirely full btree for every extent >> we have reserved for an inode. This _sucks_, because you only need to COW once, >> and then everybody else is ok. Unfortunately we don''t know we''ll all be able to >> get into the same transaction so that''s what we have had to do. But the global >> reserve holds a reservation large enough to cover a large percentage of all the >> metadata currently in the fs. So all we really need to account for is any new >> blocks that we may allocate. So fix this by >> >> 1) Passing to btrfs_alloc_free_block() wether this is a new block or a COW >> block. If it is a COW block we use the global reserve, if not we use the >> trans->block_rsv. >> 2) Reduce the amount of space we reserve. Since we don''t need to account for >> cow''ing the tree we can just keep track of new blocks to reserve, which greatly >> reduces the reservation amount. >> >> This makes my basic random write test go from 3 mb/s to 75 mb/s. I''ve tested >> this with my horrible ENOSPC test and it seems to work out fine. Thanks, >> > > Hi, Josef, > > After I patched this and did a "tar xf source.tar", I got lots of warnings, > > Would you like to look into this? > > ------------[ cut here ]------------ > WARNING: at fs/btrfs/extent-tree.c:5695 btrfs_alloc_free_block+0x178/0x340 [btrfs]() > Hardware name: QiTianM7150 > Modules linked in: btrfs iptable_nat nf_nat zlib_deflate libcrc32c ebtable_nat ebtables bridge stp llc cpufreq_ondemand acpi_cpufreq freq_table mperf be2iscsi iscsi_boot_sysfs bnx2i cnic uio cxgb3i libcxgbi cxgb3 mdio iscsi_tcp libiscsi_tcp libiscsi scsi_transport_iscsi ext3 jbd dm_mirror dm_region_hash dm_log dm_mod sg ppdev serio_raw pcspkr i2c_i801 iTCO_wdt iTCO_vendor_support sky2 parport_pc parport ext4 mbcache jbd2 sd_mod crc_t10dif pata_acpi ata_generic ata_piix i915 drm_kms_helper drm i2c_algo_bit i2c_core video [last unloaded: btrfs] > Pid: 16008, comm: umount Tainted: G W 2.6.39+ #9 > Call Trace: > [<ffffffff81053baf>] warn_slowpath_common+0x7f/0xc0 > [<ffffffff81053c0a>] warn_slowpath_null+0x1a/0x20 > [<ffffffffa04d37d8>] btrfs_alloc_free_block+0x178/0x340 [btrfs] > [<ffffffffa0501768>] ? read_extent_buffer+0xd8/0x1d0 [btrfs] > [<ffffffffa04be625>] __btrfs_cow_block+0x155/0x5f0 [btrfs] > [<ffffffffa04bebcb>] btrfs_cow_block+0x10b/0x240 [btrfs] > [<ffffffffa04c4c8e>] btrfs_search_slot+0x49e/0x7a0 [btrfs] > [<ffffffffa04d2399>] btrfs_write_dirty_block_groups+0x1a9/0x4d0 [btrfs] > [<ffffffffa0512e20>] ? btrfs_tree_unlock+0x50/0x50 [btrfs] > [<ffffffffa04df845>] commit_cowonly_roots+0x105/0x1e0 [btrfs] > [<ffffffffa04e0708>] btrfs_commit_transaction+0x428/0x850 [btrfs] > [<ffffffffa04df9b8>] ? wait_current_trans+0x28/0x100 [btrfs] > [<ffffffffa04e0c25>] ? join_transaction+0x25/0x250 [btrfs] > [<ffffffff81075590>] ? wake_up_bit+0x40/0x40 > [<ffffffffa04bb187>] btrfs_sync_fs+0x67/0xd0 [btrfs] > [<ffffffff8116c27e>] __sync_filesystem+0x5e/0x90 > [<ffffffff8116c38b>] sync_filesystem+0x4b/0x70 > [<ffffffff811441c4>] generic_shutdown_super+0x34/0xf0 > [<ffffffff81144316>] kill_anon_super+0x16/0x60 > [<ffffffff81144a25>] deactivate_locked_super+0x45/0x70 > [<ffffffff8114568a>] deactivate_super+0x4a/0x70 > [<ffffffff8115efdc>] mntput_no_expire+0x13c/0x1c0 > [<ffffffff8115f7bb>] sys_umount+0x7b/0x3a0 > [<ffffffff81466b2b>] system_call_fastpath+0x16/0x1b > ---[ end trace 9a65800674b03b84 ]--- >Hmm, not reserving enough room for the chunk tree it seems, or I screwed something up and we''re not using the right reserve. I will look into this, thanks, Josef -- To unsubscribe from this list: send the line "unsubscribe linux-btrfs" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html