On 12/01/2017 04:24 PM, Matt McKinnon wrote: > Thanks for this. Here's what I get:
Ok, and which one is displaying most of the time? > [...] > > [<ffffffffaa0a8406>] io_schedule+0x16/0x40 > [<ffffffffaa3b3cde>] get_request+0x23e/0x720 > [<ffffffffaa3b6861>] blk_queue_bio+0xc1/0x3a0 > [<ffffffffaa3b4a88>] generic_make_request+0xf8/0x2a0 > [<ffffffffaa3b4ca5>] submit_bio+0x75/0x150 > [<ffffffffc087fac5>] btrfs_map_bio+0xe5/0x2f0 [btrfs] > [<ffffffffc084834c>] btree_submit_bio_hook+0x8c/0xe0 [btrfs] > [<ffffffffc086f1e3>] submit_one_bio+0x63/0xa0 [btrfs] > [<ffffffffc086f39b>] flush_epd_write_bio+0x3b/0x50 [btrfs] > [<ffffffffc086f3be>] flush_write_bio+0xe/0x10 [btrfs] > [<ffffffffc08777a9>] btree_write_cache_pages+0x379/0x450 [btrfs] > [<ffffffffc08478ed>] btree_writepages+0x5d/0x70 [btrfs] > [<ffffffffaa1a326c>] do_writepages+0x1c/0x70 > [<ffffffffaa196f2a>] __filemap_fdatawrite_range+0xaa/0xe0 > [<ffffffffaa197023>] filemap_fdatawrite_range+0x13/0x20 > [<ffffffffc084fba9>] btrfs_write_marked_extents+0xe9/0x110 [btrfs] > [<ffffffffc084fc4d>] btrfs_write_and_wait_transaction.isra.22+0x3d/0x80 > [btrfs] > [<ffffffffc0851645>] btrfs_commit_transaction+0x665/0x900 [btrfs] > > [...] > > [<ffffffffaa0a8406>] io_schedule+0x16/0x40 > [<ffffffffaa1959c8>] wait_on_page_bit+0xe8/0x120 > [<ffffffffc087639d>] read_extent_buffer_pages+0x1cd/0x2e0 [btrfs] > [<ffffffffc0846fcf>] btree_read_extent_buffer_pages+0x9f/0x100 [btrfs] > [<ffffffffc0848542>] read_tree_block+0x32/0x50 [btrfs] > [<ffffffffc0828980>] read_block_for_search.isra.32+0x120/0x2e0 [btrfs] > [<ffffffffc082daa5>] btrfs_next_old_leaf+0x215/0x400 [btrfs] > [<ffffffffc082dca0>] btrfs_next_leaf+0x10/0x20 [btrfs] > [<ffffffffc0843c3e>] btrfs_lookup_csums_range+0x12e/0x410 [btrfs] > [<ffffffffc08d09ea>] csum_exist_in_range.isra.49+0x2a/0x81 [btrfs] > [<ffffffffc08596a2>] run_delalloc_nocow+0x9b2/0xa10 [btrfs] > [<ffffffffc0859768>] run_delalloc_range+0x68/0x340 [btrfs] > [<ffffffffc0872070>] writepage_delalloc.isra.47+0xf0/0x140 [btrfs] > [<ffffffffc0872f97>] __extent_writepage+0xc7/0x290 [btrfs] > [<ffffffffc0873415>] extent_write_cache_pages.constprop.53+0x2b5/0x450 > [btrfs] > [<ffffffffc0874fed>] extent_writepages+0x4d/0x70 [btrfs] > [<ffffffffc0852d88>] btrfs_writepages+0x28/0x30 [btrfs] > [<ffffffffaa1a326c>] do_writepages+0x1c/0x70 > [<ffffffffaa196f2a>] __filemap_fdatawrite_range+0xaa/0xe0 > [<ffffffffaa197023>] filemap_fdatawrite_range+0x13/0x20 > [<ffffffffc08695c0>] btrfs_fdatawrite_range+0x20/0x50 [btrfs] > [<ffffffffc089abf9>] __btrfs_write_out_cache+0x3d9/0x420 [btrfs] > [<ffffffffc089b066>] btrfs_write_out_cache+0x86/0x100 [btrfs] > [<ffffffffc083bc61>] btrfs_write_dirty_block_groups+0x261/0x390 [btrfs] > [<ffffffffc084e83b>] commit_cowonly_roots+0x1fb/0x290 [btrfs] > [<ffffffffc0851414>] btrfs_commit_transaction+0x434/0x900 [btrfs] 1) The one right above, btrfs_write_out_cache, is the write-out of the free space cache v1. Do you see this for multiple seconds going on, and does it match the time when it's writing X MB/s to disk? 2) How big is this filesystem? What does your `btrfs fi df /mountpoint` say? 3) What kind of workload are you running? E.g. how can you describe it within a range from "big files which just sit there" to "small writes and deletes all over the place all the time"? 4) What kernel version is this? `uname -a` output? -- Hans van Kranenburg -- To unsubscribe from this list: send the line "unsubscribe linux-btrfs" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
