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2011-06-24Btrfs: make sure to record the transid in new inodesChris Mason
When we create a new inode, we aren't filling in the field that records the transaction that last changed this inode. If we then go to fsync that inode, it will be skipped because the field isn't filled in. Signed-off-by: Chris Mason <chris.mason@oracle.com>
2011-06-15Btrfs: fix path leakage on subvol deletionJosef Bacik
The delayed ref patch accidently removed the btrfs_free_path in btrfs_unlink_subvol, this puts it back and means we don't leak a path. Thanks, Signed-off-by: Josef Bacik <josef@redhat.com>
2011-06-11Btrfs: use join_transaction in btrfs_evict_inode()Li Zefan
The WARN_ON() in start_transaction() was triggered while balancing. The cause is btrfs_relocate_chunk() started a transaction and then called iput() on the inode that stores free space cache, and iput() called btrfs_start_transaction() again. Reported-by: Tsutomu Itoh <t-itoh@jp.fujitsu.com> Signed-off-by: Li Zefan <lizf@cn.fujitsu.com> Reviewed-by: Josef Bacik <josef@redhat.com> Signed-off-by: Chris Mason <chris.mason@oracle.com>
2011-06-10Btrfs: fix extent state leak on failed nodatasum readsJan Schmidt
When encountering an EIO while reading from a nodatasum extent, we insert an error record into the inode's failure tree. btrfs_readpage_end_io_hook returns early for nodatasum inodes. We'd better clear the failure tree in that case, otherwise the kernel complains about BUG extent_state: Objects remaining on kmem_cache_close() on rmmod. Signed-off-by: Jan Schmidt <list.btrfs@jan-o-sch.net> Signed-off-by: Chris Mason <chris.mason@oracle.com>
2011-06-04btrfs: add helper for fs_info->closingDavid Sterba
wrap checking of filesystem 'closing' flag and fix a few missing memory barriers. Signed-off-by: David Sterba <dsterba@suse.cz>
2011-05-28Merge branch 'for-chris' ofChris Mason
git://git.kernel.org/pub/scm/linux/kernel/git/josef/btrfs-work into for-linus Conflicts: fs/btrfs/disk-io.c fs/btrfs/extent-tree.c fs/btrfs/free-space-cache.c fs/btrfs/inode.c fs/btrfs/transaction.c Signed-off-by: Chris Mason <chris.mason@oracle.com>
2011-05-26Btrfs: add mount -o auto_defragChris Mason
This will detect small random writes into files and queue the up for an auto defrag process. It isn't well suited to database workloads yet, but works for smaller files such as rpm, sqlite or bdb databases. Signed-off-by: Chris Mason <chris.mason@oracle.com>
2011-05-23Merge branch 'cleanups_and_fixes' into inode_numbersChris Mason
Conflicts: fs/btrfs/tree-log.c fs/btrfs/volumes.c Signed-off-by: Chris Mason <chris.mason@oracle.com>
2011-05-23fs/btrfs: Add missing btrfs_free_pathJulia Lawall
Btrfs_alloc_path should be matched with btrfs_free_path in error-handling code. A simplified version of the semantic match that finds this problem is as follows: (http://coccinelle.lip6.fr/) // <smpl> @r exists@ local idexpression struct btrfs_path * x; expression ra,rb; position p1,p2; @@ x = btrfs_alloc_path@p1(...) ... when != btrfs_free_path(x,...) when != if (...) { ... btrfs_free_path(x,...) ...} when != x = ra if(...) { ... when != x = rb when forall when != btrfs_free_path(x,...) \(return <+...x...+>; \| return@p2...; \) } @script:python@ p1 << r.p1; p2 << r.p2; @@ cocci.print_main("alloc",p1) cocci.print_secs("return",p2) // </smpl> Signed-off-by: Julia Lawall <julia@diku.dk> Signed-off-by: Chris Mason <chris.mason@oracle.com>
2011-05-23Btrfs: BUG_ON is deleted from the caller of btrfs_truncate_item & ↵Tsutomu Itoh
btrfs_extend_item Currently, btrfs_truncate_item and btrfs_extend_item returns only 0. So, the check by BUG_ON in the caller is unnecessary. Signed-off-by: Tsutomu Itoh <t-itoh@jp.fujitsu.com> Signed-off-by: Chris Mason <chris.mason@oracle.com>
2011-05-23btrfs: fix typo 'testeing' -> 'testing'Sergei Trofimovich
Signed-off-by: Sergei Trofimovich <slyfox@gentoo.org> Signed-off-by: Chris Mason <chris.mason@oracle.com>
2011-05-23Btrfs: leave spinning on lookup and map the leafJosef Bacik
On lookup we only want to read the inode item, so leave the path spinning. Also we're just wholesale reading the leaf off, so map the leaf so we don't do a bunch of kmap/kunmaps. Thanks, Signed-off-by: Josef Bacik <josef@redhat.com>
2011-05-23Btrfs: don't always do readaheadJosef Bacik
Our readahead is sort of sloppy, and really isn't always needed. For example if ls is doing a stating ls (which is the default) it's going to stat in non-disk order, so if say you have a directory with a stupid amount of files, readahead is going to do nothing but waste time in the case of doing the stat. Taking the unconditional readahead out made my test go from 57 minutes to 36 minutes. This means that everywhere we do loop through the tree we want to make sure we do set path->reada properly, so I went through and found all of the places where we loop through the path and set reada to 1. Thanks, Signed-off-by: Josef Bacik <josef@redhat.com>
2011-05-23Btrfs: kill BTRFS_I(inode)->block_groupJosef Bacik
Originally this was going to be used as a way to give hints to the allocator, but frankly we can get much better hints elsewhere and it's not even used at all for anything usefull. In addition to be completely useless, when we initialize an inode we try and find a freeish block group to set as the inodes block group, and with a completely full 40gb fs this takes _forever_, so I imagine with say 1tb fs this is just unbearable. So just axe the thing altoghether, we don't need it and it saves us 8 bytes in the inode and saves us 500 microseconds per inode lookup in my testcase. Thanks, Signed-off-by: Josef Bacik <josef@redhat.com>
2011-05-23Btrfs: fix how we do space reservation for truncateJosef Bacik
The ceph guys keep running into problems where we have space reserved in our orphan block rsv when freeing it up. This is because they tend to do snapshots alot, so their truncates tend to use a bunch of space, so when we go to do things like update the inode we have to steal reservation space in order to make the reservation happen. This happens because truncate can use as much space as it freaking feels like, but we still have to hold space for removing the orphan item and updating the inode, which will definitely always happen. So in order to fix this we need to split all of the reservation stuf up. So with this patch we have 1) The orphan block reserve which only holds the space for deleting our orphan item when everything is over. 2) The truncate block reserve which gets allocated and used specifically for the space that the truncate will use on a per truncate basis. 3) The transaction will always have 1 item's worth of data reserved so we can update the inode normally. Hopefully this will make the ceph problem go away. Thanks, Signed-off-by: Josef Bacik <josef@redhat.com>
2011-05-23Btrfs: take away the num_items argument from btrfs_join_transactionJosef Bacik
I keep forgetting that btrfs_join_transaction() just ignores the num_items argument, which leads me to sending pointless patches and looking stupid :). So just kill the num_items argument from btrfs_join_transaction and btrfs_start_ioctl_transaction, since neither of them use it. Thanks, Signed-off-by: Josef Bacik <josef@redhat.com>
2011-05-23Btrfs: make sure to use the delalloc reserve when filling delallocJosef Bacik
In the prealloc filling code and compressed code we don't set trans->block_rsv to the delalloc block reserve properly, which is going to make us use metadata from the wrong pool, this patch fixes that. Thanks, Signed-off-by: Josef Bacik <josef@redhat.com>
2011-05-23Merge branch 'for-chris' of ↵Chris Mason
git://git.kernel.org/pub/scm/linux/kernel/git/arne/btrfs-unstable-arne into inode_numbers Conflicts: fs/btrfs/Makefile fs/btrfs/ctree.h fs/btrfs/volumes.h Signed-off-by: Chris Mason <chris.mason@oracle.com>
2011-05-22Merge branch 'cleanups' of git://repo.or.cz/linux-2.6/btrfs-unstable into ↵Chris Mason
inode_numbers Conflicts: fs/btrfs/extent-tree.c fs/btrfs/free-space-cache.c fs/btrfs/inode.c fs/btrfs/tree-log.c Signed-off-by: Chris Mason <chris.mason@oracle.com>
2011-05-22Merge branch 'delayed_inode' into inode_numbersChris Mason
Conflicts: fs/btrfs/inode.c fs/btrfs/ioctl.c fs/btrfs/transaction.c Signed-off-by: Chris Mason <chris.mason@oracle.com>
2011-05-21btrfs: implement delayed inode items operationMiao Xie
Changelog V5 -> V6: - Fix oom when the memory load is high, by storing the delayed nodes into the root's radix tree, and letting btrfs inodes go. Changelog V4 -> V5: - Fix the race on adding the delayed node to the inode, which is spotted by Chris Mason. - Merge Chris Mason's incremental patch into this patch. - Fix deadlock between readdir() and memory fault, which is reported by Itaru Kitayama. Changelog V3 -> V4: - Fix nested lock, which is reported by Itaru Kitayama, by updating space cache inode in time. Changelog V2 -> V3: - Fix the race between the delayed worker and the task which does delayed items balance, which is reported by Tsutomu Itoh. - Modify the patch address David Sterba's comment. - Fix the bug of the cpu recursion spinlock, reported by Chris Mason Changelog V1 -> V2: - break up the global rb-tree, use a list to manage the delayed nodes, which is created for every directory and file, and used to manage the delayed directory name index items and the delayed inode item. - introduce a worker to deal with the delayed nodes. Compare with Ext3/4, the performance of file creation and deletion on btrfs is very poor. the reason is that btrfs must do a lot of b+ tree insertions, such as inode item, directory name item, directory name index and so on. If we can do some delayed b+ tree insertion or deletion, we can improve the performance, so we made this patch which implemented delayed directory name index insertion/deletion and delayed inode update. Implementation: - introduce a delayed root object into the filesystem, that use two lists to manage the delayed nodes which are created for every file/directory. One is used to manage all the delayed nodes that have delayed items. And the other is used to manage the delayed nodes which is waiting to be dealt with by the work thread. - Every delayed node has two rb-tree, one is used to manage the directory name index which is going to be inserted into b+ tree, and the other is used to manage the directory name index which is going to be deleted from b+ tree. - introduce a worker to deal with the delayed operation. This worker is used to deal with the works of the delayed directory name index items insertion and deletion and the delayed inode update. When the delayed items is beyond the lower limit, we create works for some delayed nodes and insert them into the work queue of the worker, and then go back. When the delayed items is beyond the upper bound, we create works for all the delayed nodes that haven't been dealt with, and insert them into the work queue of the worker, and then wait for that the untreated items is below some threshold value. - When we want to insert a directory name index into b+ tree, we just add the information into the delayed inserting rb-tree. And then we check the number of the delayed items and do delayed items balance. (The balance policy is above.) - When we want to delete a directory name index from the b+ tree, we search it in the inserting rb-tree at first. If we look it up, just drop it. If not, add the key of it into the delayed deleting rb-tree. Similar to the delayed inserting rb-tree, we also check the number of the delayed items and do delayed items balance. (The same to inserting manipulation) - When we want to update the metadata of some inode, we cached the data of the inode into the delayed node. the worker will flush it into the b+ tree after dealing with the delayed insertion and deletion. - We will move the delayed node to the tail of the list after we access the delayed node, By this way, we can cache more delayed items and merge more inode updates. - If we want to commit transaction, we will deal with all the delayed node. - the delayed node will be freed when we free the btrfs inode. - Before we log the inode items, we commit all the directory name index items and the delayed inode update. I did a quick test by the benchmark tool[1] and found we can improve the performance of file creation by ~15%, and file deletion by ~20%. Before applying this patch: Create files: Total files: 50000 Total time: 1.096108 Average time: 0.000022 Delete files: Total files: 50000 Total time: 1.510403 Average time: 0.000030 After applying this patch: Create files: Total files: 50000 Total time: 0.932899 Average time: 0.000019 Delete files: Total files: 50000 Total time: 1.215732 Average time: 0.000024 [1] http://marc.info/?l=linux-btrfs&m=128212635122920&q=p3 Many thanks for Kitayama-san's help! Signed-off-by: Miao Xie <miaox@cn.fujitsu.com> Reviewed-by: David Sterba <dave@jikos.cz> Tested-by: Tsutomu Itoh <t-itoh@jp.fujitsu.com> Tested-by: Itaru Kitayama <kitayama@cl.bb4u.ne.jp> Signed-off-by: Chris Mason <chris.mason@oracle.com>
2011-05-21Merge branch 'ino-alloc' of git://repo.or.cz/linux-btrfs-devel into ↵Chris Mason
inode_numbers Conflicts: fs/btrfs/free-space-cache.c Signed-off-by: Chris Mason <chris.mason@oracle.com>
2011-05-12btrfs: use printk_ratelimited instead of printk_ratelimitDavid Sterba
As per printk_ratelimit comment, it should not be used. Signed-off-by: David Sterba <dsterba@suse.cz>
2011-05-12btrfs: scrubArne Jansen
This adds an initial implementation for scrub. It works quite straightforward. The usermode issues an ioctl for each device in the fs. For each device, it enumerates the allocated device chunks. For each chunk, the contained extents are enumerated and the data checksums fetched. The extents are read sequentially and the checksums verified. If an error occurs (checksum or EIO), a good copy is searched for. If one is found, the bad copy will be rewritten. All enumerations happen from the commit roots. During a transaction commit, the scrubs get paused and afterwards continue from the new roots. This commit is based on the series originally posted to linux-btrfs with some improvements that resulted from comments from David Sterba, Ilya Dryomov and Jan Schmidt. Signed-off-by: Arne Jansen <sensille@gmx.net>
2011-05-06btrfs: remove old unused commented out codeDavid Sterba
Remove code which has been #if0-ed out for a very long time and does not seem to be related to current codebase anymore. Signed-off-by: David Sterba <dsterba@suse.cz>
2011-05-06btrfs: remove all unused functionsDavid Sterba
Remove static and global declarations and/or definitions. Reduces size of btrfs.ko by ~3.4kB. text data bss dec hex filename 402081 7464 200 409745 64091 btrfs.ko.base 398620 7144 200 405964 631cc btrfs.ko.remove-all Signed-off-by: David Sterba <dsterba@suse.cz>
2011-05-02btrfs: drop unused parameter from btrfs_release_pathDavid Sterba
parameter tree root it's not used since commit 5f39d397dfbe140a14edecd4e73c34ce23c4f9ee ("Btrfs: Create extent_buffer interface for large blocksizes") Signed-off-by: David Sterba <dsterba@suse.cz>
2011-05-02btrfs: drop gfp parameter from alloc_extent_mapDavid Sterba
pass GFP_NOFS directly to kmem_cache_alloc Signed-off-by: David Sterba <dsterba@suse.cz>
2011-05-02btrfs: drop unused parameter from extent_map_tree_initDavid Sterba
the GFP flags are not stored anywhere and all allocations are done via alloc_extent_map(GFP_NOFS). Signed-off-by: David Sterba <dsterba@suse.cz>
2011-05-02btrfs: drop unused argument from extent_io_tree_initDavid Sterba
all callers pass GFP_NOFS, but the GFP mask argument is not used in the function; GFP_ATOMIC is passed to radix tree initialization and it's the only correct one, since we're using the preload/insert mechanism of radix tree. Let's drop the gfp mask from btrfs function, this will not change behaviour. Signed-off-by: David Sterba <dsterba@suse.cz>
2011-05-02btrfs: unify checking of IS_ERR and nullDavid Sterba
use IS_ERR_OR_NULL when possible, done by this coccinelle script: @ match @ identifier id; @@ ( - BUG_ON(IS_ERR(id) || !id); + BUG_ON(IS_ERR_OR_NULL(id)); | - IS_ERR(id) || !id + IS_ERR_OR_NULL(id) | - !id || IS_ERR(id) + IS_ERR_OR_NULL(id) ) Signed-off-by: David Sterba <dsterba@suse.cz>
2011-05-02btrfs: rename variables clashing with global function namesDavid Sterba
reported by gcc -Wshadow: page_index, page_offset, new_inode, dev_name Signed-off-by: David Sterba <dsterba@suse.cz>
2011-04-26Merge git://git.kernel.org/pub/scm/linux/kernel/git/mason/btrfs-unstableLinus Torvalds
* git://git.kernel.org/pub/scm/linux/kernel/git/mason/btrfs-unstable: Btrfs: cleanup error handling in inode.c Btrfs: put the right bio if we have an error Btrfs: free bitmaps properly when evicting the cache Btrfs: Free free_space item properly in btrfs_trim_block_group() btrfs: add missing spin_unlock to a rare exit path Btrfs: check return value of kmalloc() btrfs: fix wrong allocating flag when reading page Btrfs: fix missing mutex_unlock in btrfs_del_dir_entries_in_log()
2011-04-25Btrfs: cleanup error handling in inode.cTsutomu Itoh
The error processing of several places is changed like setting the error number only at the error. Signed-off-by: Tsutomu Itoh <t-itoh@jp.fujitsu.com> Signed-off-by: Chris Mason <chris.mason@oracle.com>
2011-04-25Btrfs: put the right bio if we have an errorJosef Bacik
In btrfs_submit_direct_hook if the first btrfs_map_block fails we need to put the orig_bio, not bio. Signed-off-by: Josef Bacik <josef@redhat.com> Signed-off-by: Chris Mason <chris.mason@oracle.com>
2011-04-25Btrfs: check return value of kmalloc()Tsutomu Itoh
The check on the return value of kmalloc() is added to some places. Signed-off-by: Tsutomu Itoh <t-itoh@jp.fujitsu.com> Signed-off-by: Chris Mason <chris.mason@oracle.com>
2011-04-25Btrfs: Support reading/writing on disk free ino cacheLi Zefan
This is similar to block group caching. We dedicate a special inode in fs tree to save free ino cache. At the very first time we create/delete a file after mount, the free ino cache will be loaded from disk into memory. When the fs tree is commited, the cache will be written back to disk. To keep compatibility, we check the root generation against the generation of the special inode when loading the cache, so the loading will fail if the btrfs filesystem was mounted in an older kernel before. Signed-off-by: Li Zefan <lizf@cn.fujitsu.com>
2011-04-25Btrfs: Always use 64bit inode numberLi Zefan
There's a potential problem in 32bit system when we exhaust 32bit inode numbers and start to allocate big inode numbers, because btrfs uses inode->i_ino in many places. So here we always use BTRFS_I(inode)->location.objectid, which is an u64 variable. There are 2 exceptions that BTRFS_I(inode)->location.objectid != inode->i_ino: the btree inode (0 vs 1) and empty subvol dirs (256 vs 2), and inode->i_ino will be used in those cases. Another reason to make this change is I'm going to use a special inode to save free ino cache, and the inode number must be > (u64)-256. Signed-off-by: Li Zefan <lizf@cn.fujitsu.com>
2011-04-25Btrfs: Cache free inode numbers in memoryLi Zefan
Currently btrfs stores the highest objectid of the fs tree, and it always returns (highest+1) inode number when we create a file, so inode numbers won't be reclaimed when we delete files, so we'll run out of inode numbers as we keep create/delete files in 32bits machines. This fixes it, and it works similarly to how we cache free space in block cgroups. We start a kernel thread to read the file tree. By scanning inode items, we know which chunks of inode numbers are free, and we cache them in an rb-tree. Because we are searching the commit root, we have to carefully handle the cross-transaction case. The rb-tree is a hybrid extent+bitmap tree, so if we have too many small chunks of inode numbers, we'll use bitmaps. Initially we allow 16K ram of extents, and a bitmap will be used if we exceed this threshold. The extents threshold is adjusted in runtime. Signed-off-by: Li Zefan <lizf@cn.fujitsu.com>
2011-04-18Merge git://git.kernel.org/pub/scm/linux/kernel/git/mason/btrfs-unstableLinus Torvalds
* git://git.kernel.org/pub/scm/linux/kernel/git/mason/btrfs-unstable: (24 commits) Btrfs: fix free space cache leak Btrfs: avoid taking the chunk_mutex in do_chunk_alloc Btrfs end_bio_extent_readpage should look for locked bits Btrfs: don't force chunk allocation in find_free_extent Btrfs: Check validity before setting an acl Btrfs: Fix incorrect inode nlink in btrfs_link() Btrfs: Check if btrfs_next_leaf() returns error in btrfs_real_readdir() Btrfs: Check if btrfs_next_leaf() returns error in btrfs_listxattr() Btrfs: make uncache_state unconditional btrfs: using cached extent_state in set/unlock combinations Btrfs: avoid taking the trans_mutex in btrfs_end_transaction Btrfs: fix subvolume mount by name problem when default mount subvolume is set fix user annotation in ioctl.c Btrfs: check for duplicate iov_base's when doing dio reads btrfs: properly handle overlapping areas in memmove_extent_buffer Btrfs: fix memory leaks in btrfs_new_inode() Btrfs: check for duplicate iov_base's when doing dio reads Btrfs: reuse the extent_map we found when calling btrfs_get_extent Btrfs: do not use async submit for small DIO io's Btrfs: don't split dio bios if we don't have to ...
2011-04-13Btrfs: Fix incorrect inode nlink in btrfs_link()Miao Xie
Link count of the inode is not decreased if btrfs_set_inode_index() fails. Signed-off-by: Miao Xie <miaox@cn.fujitsu.com> Singed-off-by: Li Zefan <lizf@cn.fujitsu.com>
2011-04-13Btrfs: Check if btrfs_next_leaf() returns error in btrfs_real_readdir()Li Zefan
btrfs_next_leaf() can return -errno, and we should propagate it to userspace. This also simplifies how we walk the btree path. Signed-off-by: Li Zefan <lizf@cn.fujitsu.com>
2011-04-11Merge branch 'for-chris' of ↵Chris Mason
git://git.kernel.org/pub/scm/linux/kernel/git/josef/btrfs-work into for-linus
2011-04-11btrfs: using cached extent_state in set/unlock combinationsArne Jansen
In several places the sequence (set_extent_uptodate, unlock_extent) is used. This leads to a duplicate lookup of the extent state. This patch lets set_extent_uptodate return a cached extent_state which can be passed to unlock_extent_cached. The occurences of the above sequences are updated to use the cache. Only end_bio_extent_readpage is updated that it first gets a cached state to pass it to the readpage_end_io_hook as the prototype requested and is later on being used for set/unlock. Signed-off-by: Arne Jansen <sensille@gmx.net> Signed-off-by: Chris Mason <chris.mason@oracle.com>
2011-04-11Btrfs: check for duplicate iov_base's when doing dio readsJosef Bacik
Apparently it is ok to submit a read to an IDE device with the same target page for different offsets. This is what Windows does under qemu. The problem is under DIO we expect them to be different buffers for checksumming reasons, and so this sort of thing will result in checksum errors, when in reality the file is fine. So when reading, check to make sure that all iov bases are different, and if they aren't fall back to buffered mode, since that will work out right. Thanks, Signed-off-by: Josef Bacik <josef@redhat.com> Signed-off-by: Chris Mason <chris.mason@oracle.com>
2011-04-11Btrfs: fix memory leaks in btrfs_new_inode()Yoshinori Sano
This patch fixes memory leaks in btrfs_new_inode(). Signed-off-by: Yoshinori Sano <yoshinori.sano@gmail.com> Signed-off-by: Chris Mason <chris.mason@oracle.com>
2011-04-08Btrfs: check for duplicate iov_base's when doing dio readsJosef Bacik
Apparently it is ok to submit a read to an IDE device with the same target page for different offsets. This is what Windows does under qemu. The problem is under DIO we expect them to be different buffers for checksumming reasons, and so this sort of thing will result in checksum errors, when in reality the file is fine. So when reading, check to make sure that all iov bases are different, and if they aren't fall back to buffered mode, since that will work out right. Thanks, Signed-off-by: Josef Bacik <josef@redhat.com>
2011-04-08Btrfs: reuse the extent_map we found when calling btrfs_get_extentJosef Bacik
In btrfs_get_block_direct we call btrfs_get_extent to lookup the extent for the range that we are looking for. If we don't find an extent, btrfs_get_extent will insert a extent_map for that area and mark it as a hole. So it does the job of allocating a new extent map and inserting it into the io tree. But if we're creating a new extent we free it up and redo all of that work. So instead pass the em to btrfs_new_extent_direct(), and if it will work just allocate the disk space and set it up properly and bypass the freeing/allocating of a new extent map and the expensive operation of inserting the thing into the io_tree. Thanks, Signed-off-by: Josef Bacik <josef@redhat.com>
2011-04-08Btrfs: do not use async submit for small DIO io'sJosef Bacik
When looking at our DIO performance Chris said that for small IO's doing the async submit stuff tends to be more overhead than it's worth. With this on top of my other fixes I get about a 17-20% speedup doing a sequential dd with 4k IO's. Basically if we don't have to split the bio for the map length it's small enough to be directly submitted, otherwise go back to the async submit. Thanks, Signed-off-by: Josef Bacik <josef@redhat.com>
2011-04-08Btrfs: don't split dio bios if we don't have toJosef Bacik
We have been unconditionally allocating a new bio and re-adding all pages from our original bio to the new bio. This is needed if our original bio is larger than our stripe size, but if it is smaller than the stripe size then there is no need to do this. So check the map length and if we are under that then go ahead and submit the original bio. Thanks, Signed-off-by: Josef Bacik <josef@redhat.com>