From 1449032be17abb69116dbc393f67ceb8bd034f92 Mon Sep 17 00:00:00 2001 From: Theodore Ts'o Date: Tue, 14 Dec 2010 15:27:50 -0500 Subject: ext4: Turn off multiple page-io submission by default Jon Nelson has found a test case which causes postgresql to fail with the error: psql:t.sql:4: ERROR: invalid page header in block 38269 of relation base/16384/16581 Under memory pressure, it looks like part of a file can end up getting replaced by zero's. Until we can figure out the cause, we'll roll back the change and use block_write_full_page() instead of ext4_bio_write_page(). The new, more efficient writing function can be used via the mount option mblk_io_submit, so we can test and fix the new page I/O code. To reproduce the problem, install postgres 8.4 or 9.0, and pin enough memory such that the system just at the end of triggering writeback before running the following sql script: begin; create temporary table foo as select x as a, ARRAY[x] as b FROM generate_series(1, 10000000 ) AS x; create index foo_a_idx on foo (a); create index foo_b_idx on foo USING GIN (b); rollback; If the temporary table is created on a hard drive partition which is encrypted using dm_crypt, then under memory pressure, approximately 30-40% of the time, pgsql will issue the above failure. This patch should fix this problem, and the problem will come back if the file system is mounted with the mblk_io_submit mount option. Reported-by: Jon Nelson Signed-off-by: "Theodore Ts'o" --- fs/ext4/ext4.h | 1 + 1 file changed, 1 insertion(+) (limited to 'fs/ext4/ext4.h') diff --git a/fs/ext4/ext4.h b/fs/ext4/ext4.h index 6a5edea2d70b..94ce3d7a1c4b 100644 --- a/fs/ext4/ext4.h +++ b/fs/ext4/ext4.h @@ -910,6 +910,7 @@ struct ext4_inode_info { #define EXT4_MOUNT_JOURNAL_CHECKSUM 0x800000 /* Journal checksums */ #define EXT4_MOUNT_JOURNAL_ASYNC_COMMIT 0x1000000 /* Journal Async Commit */ #define EXT4_MOUNT_I_VERSION 0x2000000 /* i_version support */ +#define EXT4_MOUNT_MBLK_IO_SUBMIT 0x4000000 /* multi-block io submits */ #define EXT4_MOUNT_DELALLOC 0x8000000 /* Delalloc support */ #define EXT4_MOUNT_DATA_ERR_ABORT 0x10000000 /* Abort on file data write */ #define EXT4_MOUNT_BLOCK_VALIDITY 0x20000000 /* Block validity checking */ -- cgit v1.2.3