search for: delalloc

Hi all. I was doing some testing with writing out data to a BTFS filesystem with the compress-force option. With 1 program running, I saw btfs-delalloc taking about 1 CPU worth of time, much as could be expected. I then started up 2 programs at the same time, writing data to the BTRFS volume. btrfs-delalloc still only used 1 CPU worth of time. Is btrfs-delalloc threaded, to where it can use more than 1 CPU worth of time? Is there a threshold w...

Greetings all, I see the following issue during snap creation under IO: Transaction commit calls btrfs_start_delalloc_inodes() that locks the delalloc_inodes list, fetches the first inode, unlocks the list, triggers btrfs_alloc_delalloc_work/btrfs_queue_worker for this inode and then locks the list again. Then it checks the head of the list again. In my case, this is always exactly the same inode. As a result, thi...

Liu fixed part of this problem and unfortunately I steered him in slightly the wrong direction and so didn''t completely fix the problem. The problem is we limit the size of the delalloc range we are looking for to max bytes and then we try to lock that range. If we fail to lock the pages in that range we will shrink the max bytes to a single page and re loop. However if our first page is inside of the delalloc range then we will end up limiting the end of the range to a period b...

Hello all. What we have: SL6 - kernel 2.6.32-131.2.1.el6.x86_64 btrfs on mdadm RAID5 with 8 HDD - 27T partition. I see this at top: 1182 root 20 0 0 0 0 R 100.0 0.0 16:39.73 [btrfs-delalloc-] And LA is grow. What is this and how can I fix it? -- Best regards, Proskurin Kirill -- 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

.../fs/btrfs/extent-tree.c +++ b/fs/btrfs/extent-tree.c @@ -3941,12 +3941,11 @@ static void btrfs_writeback_inodes_sb_nr(struct btrfs_root *root, unsigned long nr_pages) { struct super_block *sb = root->fs_info->sb; - int started; - /* If we can not start writeback, just sync all the delalloc file. */ - started = try_to_writeback_inodes_sb_nr(sb, nr_pages, - WB_REASON_FS_FREE_SPACE); - if (!started) { + if (down_read_trylock(&sb->s_umount)) { + writeback_inodes_sb_nr(sb, nr_pages, WB_REASON_FS_FREE_SPACE); + up_read(&sb->s_umount); + } else { /* * We ne...

When using delalloc workers in a non-waiting way (like for enospc handling) we can end up not actually waiting for the dirty pages to be started if we have compression. We need to add an extra filemap flush to make sure any async extents that have started are actually moved along before returning. Thanks, Signed-of...

When testing with max_extents=4k, we enospc out really really early. The reason for this is we really overwhelm the system with our worst case calculation. When we try to flush delalloc, we don''t want everybody to wait around forever, so we wake up the waiters when we''ve done some of the work in hopes that its enough work to get everything they need done. The problem with this is we don''t wait long enough sometimes. So if we''ve already done a...

So both Liu and I made huge messes of find_lock_delalloc_range trying to fix stuff, me first by fixing extent size, then him by fixing something I broke and then me again telling him to fix it a different way. So this is obviously a candidate for some testing. This patch adds a pseudo fs so we can allocate fake inodes for tests that need an inode or pa...

On 06/30/2011 09:13 PM, Josef Bacik wrote: > On 06/30/2011 10:12 AM, Proskurin Kirill wrote: >> On 06/29/2011 08:14 PM, Josef Bacik wrote: >>>> Ok - I upgrade to 2.6.39-2 but it is seems to all things get worse. >>>> Now I see [btrfs-transacti]& btrfs-endio-wri] 80-100% all the time and >>>> io performance looks like lower then before.

We are running a benchmark that does single threaded 512 KB writes to a LUN on a CLARiiON storage array. The dual Xeon host (Dell 2650) with 4 GB of memory runs RHEL 4U3 We measured the write bandwidth for writes to the block device corresponding to the lun (e.g. /dev/sdb), a file in an ext2 filesystem and to a file in an ext3 file system. Write b/w for 512 KB writes Block device 312 MBps Ext2

...Modules linked in: microcode psmouse serio_raw ioatdma i7core_edac joydev lp edac_core dca parport raid10 raid456 async_raid6_recov async_pq usbhid hid raid6_pq async_xor xor async_memcpy async_tx raid1 raid0 multipath linear ahci btrfs zlib_deflate libahci e1000e libcrc32c Pid: 1119, comm: btrfs-delalloc- Tainted: G W 2.6.38-020638-generic #201103151303 Supermicro X8STi/X8STi RIP: 0010:[<ffffffffa00e23cb>] [<ffffffffa00e23cb>] write_extent_buffer+0xbb/0x1b0 [btrfs] RSP: 0018:ffff880303a0bbc0 EFLAGS: 00010a86 RAX: db74000000000000 RBX: 0000000000000d26 RCX: ffff880000000000 RDX:...

...ipmi_msghandler iTCO_vendor_support shpchp pcspkr button edac_core container pci_hotplug evdev ext3 jbd mbcache usbhid hid ehci_hcd uhci_hcd bnx2 usbcore cciss scsi_mod dm_mirror dm_region_hash dm_log dm_snapshot dm_mod thermal processor fan thermal_sys fuse [12812.265344] Pid: 8175, comm: btrfs-delalloc- Not tainted 2.6.28-rc5-btrfs #1 [12812.265344] RIP: 0010:[<ffffffff803ba943>] [<ffffffff803ba943>] fill_window+0x143/0x480 [12812.265344] RSP: 0018:ffff8807b44dfc80 EFLAGS: 00010212 [12812.265344] RAX: 0000000000001000 RBX: 0000000000001000 RCX: b6e3880000000000 [12812.265344] RDX...

We only need an async starter if we can''t make a GFP_NOFS allocation in our current path. This is the case for the endio stuff since it happens in IRQ context, but things like the caching thread workers and the delalloc flushers we can easily make this allocation and start threads right away. Also change the worker count for the caching thread pool. Traditionally we limited this to 2 since we took read locks while caching, but nowadays we do this lockless so there''s no reason to limit the number of cach...

All, I'm requesting comments from the expert readers of ext3-users on these notes for tuning ext3 for performance. Most helpful would be feedback pertinent to RHEL 5; as XFS isn't supported under Red Hat Enterprise Linux these items are an attempt to match XFS performance with ext3. These items were culled from a number of sources. Will they be effective for achieving the performance

...diff --git a/fs/btrfs/inode.c b/fs/btrfs/inode.c index 0ccc743..d42bea4 100644 --- a/fs/btrfs/inode.c +++ b/fs/btrfs/inode.c @@ -882,7 +882,7 @@ static noinline int cow_file_range(struct inode *inode, */ op = unlock ? EXTENT_CLEAR_UNLOCK_PAGE : 0; op |= EXTENT_CLEAR_UNLOCK | EXTENT_CLEAR_DELALLOC | - EXTENT_SET_PRIVATE2; + EXTENT_SET_PRIVATE2; extent_clear_unlock_delalloc(inode, &BTRFS_I(inode)->io_tree, start, start + ram_size - 1, @@ -1778,6 +1778,9 @@ static int btrfs_finish_ordered_io(struct inode *inode, u64 start, u64 end) ordered_extent->len...

...n, which I have implemented in this version: - use u64 to return the result - replaced the loop while (1) { struct btrfs_ordered_extent *ordered; lock_extent(&BTRFS_I(inode)->io_tree, 0, len, GFP_NOFS); ordered = btrfs_lookup_first_ordered_extent(inode, len); if (BTRFS_I(inode)->delalloc_bytes == 0 && !ordered) break; unlock_extent(&BTRFS_I(inode)->io_tree, 0, len, GFP_NOFS); if (ordered) btrfs_put_ordered_extent(ordered); btrfs_wait_ordered_range(inode, 0, len); } with btrfs_wait_ordered_range(inode, 0, (u64)-1); - return the uncompressed size on dis...

...only reported 50% to be in use, which is far from the 75% limit people mention on the ML. Note that this occurs using a vanilla 2.6.32-rc5 kernel on a 64-bit gentoo system. Error-message from logs: 2009-11-05T07:55:57.586574+00:00 PulsarX4 kernel: [ 136.095961] no space left, need 4096, 4440064 delalloc bytes, 10704142336 bytes_used, 0 bytes_reserved, 0 bytes_pinned, 0 bytes_readonly, 0 may use 10708582400 total 2009-11-05T07:55:57.645314+00:00 PulsarX4 kernel: [ 136.154217] no space left, need 4096, 4448256 delalloc bytes, 10704134144 bytes_used, 0 bytes_reserved, 0 bytes_pinned, 0 bytes_readonl...

.../btrfs-unstable-standalone/extent-tree.c:2437!^M Nov 12 22:39:13 Intrepid-btrfs kernel: [ 2531.816012] invalid opcode: 0000 [#1] SMP ^M Nov 12 22:39:13 Intrepid-btrfsNov 12 22:39:13 Intrepid-btrfs kernel: [ 2531.816012] ^M Nov 12 22:39:13 Intrepid-btrfs kernel: [ 2531.816012] Pid: 5193, comm: btrfs-delalloc- Not tainted (2.6.27-7-generic #1)^M Nov 12 22:39:13 Intrepid-btrfs kernel: [ 2531.816012] EIP: 0060:[<e08d2b62>] EFLAGS: 00010257 CPU: 0^M Nov 12 22:39:13 Intrepid-btrfs kernel: [ 2531.816012] EIP is at __btrfs_reserve_extent+0x3c2/0x480 [btrfs]^M Nov 12 22:39:13 Intrepid-btrfs kernel: [ 253...

After running ceph on XFS for some time, I decided to try btrfs again. Performance with the current "for-linux-min" branch and big metadata is much better. The only problem (?) I''m still seeing is a warning that seems to occur from time to time: [87703.784552] ------------[ cut here ]------------ [87703.789759] WARNING: at fs/btrfs/inode.c:2103

...unks since we never had a real view of how much space was actually in use by metadata. There are a lot of fixes in here to make this work, but the biggest things are this 1) When we make a disk reservation we drop bytes_may_use and add to bytes_reserved. We didn''t use to do this because delalloc would update bytes_may_use when it cleared delalloc. So now we don''t do this, we only will update bytes_may_use if we have an error and have to clear the accounting manually. 2) In should_alloc_chunk() we need to take into account the global_rsv size since that is basically used space....