Quanah Gibson-Mount quanah@fast-mail.org schrieb am 19.01.2023 um 19:18 in
Nachricht <CC305D834224C2ADDA932D55@[192.168.1.14]>:
--On Thursday, January 19, 2023 8:25 AM +0100 Ulrich Windl Ulrich.Windl@rz.uni-regensburg.de wrote:
Quanah Gibson-Mount quanah@fast-mail.org schrieb am 18.01.2023 um 14:50 in
Nachricht <3D6804DEBBC5413284159965@[192.168.1.14]>:
...
I would note that it is not advised to use XFS with back-mdb.
Would you explain why? Here we use XFS for all database filesystems.
The filesystem journaling done by XFS is not required for back-mdb databases and imposes a significant performance penalty for write operations. Unlike ext4 partitions it is not possible to disable the filesystem journal. The best option for back-mdb databases on XFS is to tell XFS to use a external journal.
OK, but it seems to me that XFS (as most others, too) does metadata journaling only. The man page says: "The log section (or area, if it is internal to the data section) is used to store changes to filesystem metadata while the filesystem is running until those changes are made to the data section."
Also you could set logdev= to a very fast device.
Inspecting the log of our most busy database's redo logs, it does not look as if data is in the journal; using xfs_logprint, I got:
xfs_logprint: xfs_logprint: /dev/mapper/DB--log1 contains a mounted and writable filesystem data device: 0xfe1c log device: 0xfe1c daddr: 5242784 length: 20480
log tail: 15104 head: 15200 state: <DIRTY>
LOG REC AT LSN cycle 7883 block 15104 (0x1ecb, 0x3b00) ============================================================================ TRANS: tid:0x37efb8bb #items:4 trans:0x37efb8bb q:0x1570870 INO: cnt:2 total:2 a:0x1582320 len:56 a:0x1582360 len:96 INODE: #regs:2 ino:0x84 flags:0x1 dsize:0 CORE inode: INO: cnt:2 total:2 a:0x1581f00 len:56 a:0x1581f70 len:96 INODE: #regs:2 ino:0x85 flags:0x1 dsize:0 CORE inode:
LOG REC AT LSN cycle 7883 block 15136 (0x1ecb, 0x3b20) ============================================================================ TRANS: tid:0x17345a71 #items:2 trans:0x17345a71 q:0x1570870 INO: cnt:2 total:2 a:0x1581f00 len:56 a:0x1581f70 len:96 INODE: #regs:2 ino:0x85 flags:0x1 dsize:0 CORE inode:
LOG REC AT LSN cycle 7883 block 15168 (0x1ecb, 0x3b40) ============================================================================ TRANS: tid:0xb6533eee #items:4 trans:0xb6533eee q:0x1570870 INO: cnt:2 total:2 a:0x1581f00 len:56 a:0x1581f70 len:96 INODE: #regs:2 ino:0x84 flags:0x1 dsize:0 CORE inode: INO: cnt:2 total:2 a:0x1582320 len:56 a:0x1582360 len:96 INODE: #regs:2 ino:0x85 flags:0x1 dsize:0 CORE inode: --- to me "dsize:0" looks as if no data is in the entries.
The "data" filesystem seems a bit more busy: xfs_logprint: xfs_logprint: /dev/mapper/DB--data contains a mounted and writable filesystem data device: 0xfe1b log device: 0xfe1b daddr: 1258290720 length: 1228800
log tail: 404544 head: 404608 state: <DIRTY>
LOG REC AT LSN cycle 151 block 404544 (0x97, 0x62c40) ============================================================================ TRANS: tid:0x58198a01 #items:136 trans:0x58198a01 q:0x1b24870 INO: cnt:2 total:2 a:0x1b36320 len:56 a:0x1b36360 len:96 INODE: #regs:2 ino:0x400056c1 flags:0x1 dsize:0 CORE inode: INO: cnt:2 total:2 a:0x1b35f00 len:56 a:0x1b35f70 len:96 INODE: #regs:2 ino:0x1e0032bb1 flags:0x1 dsize:0 CORE inode: INO: cnt:2 total:2 a:0x1b3e410 len:56 a:0x1b3e4b0 len:96 INODE: #regs:2 ino:0x100f0fbb flags:0x1 dsize:0 CORE inode: INO: cnt:2 total:2 a:0x1b3e520 len:56 a:0x1b3e5c0 len:96 INODE: #regs:2 ino:0xa0017c68 flags:0x1 dsize:0 CORE inode: INO: cnt:2 total:2 a:0x1b3e630 len:56 a:0x1b3e6d0 len:96 INODE: #regs:2 ino:0x200068a0 flags:0x1 dsize:0 CORE inode: INO: cnt:2 total:2 a:0x1b3e740 len:56 a:0x1b3e7e0 len:96 INODE: #regs:2 ino:0x180001fb1 flags:0x1 dsize:0 CORE inode: INO: cnt:2 total:2 a:0x1b3e850 len:56 a:0x1b3e8f0 len:96 INODE: #regs:2 ino:0xe0002221 flags:0x1 dsize:0 CORE inode: INO: cnt:2 total:2 a:0x1b3e960 len:56 a:0x1b3ea00 len:96 INODE: #regs:2 ino:0xc056db7f flags:0x1 dsize:0 CORE inode: INO: cnt:2 total:2 a:0x1b3ea70 len:56 a:0x1b3eb10 len:96 INODE: #regs:2 ino:0x87534f87 flags:0x1 dsize:0 CORE inode: INO: cnt:2 total:2 a:0x1b3eb80 len:56 a:0x1b3ec20 len:96 INODE: #regs:2 ino:0x100f0fbf flags:0x1 dsize:0 CORE inode: INO: cnt:2 total:2 a:0x1b3ec90 len:56 a:0x1b3ed30 len:96 INODE: #regs:2 ino:0xb0006f44 flags:0x1 dsize:0 CORE inode: INO: cnt:2 total:2 a:0x1b3eda0 len:56 a:0x1b3ee40 len:96 INODE: #regs:2 ino:0x4d6f1 flags:0x1 dsize:0 CORE inode: INO: cnt:2 total:2 a:0x1b3eeb0 len:56 a:0x1b3ef50 len:96 INODE: #regs:2 ino:0x500f38ce flags:0x1 dsize:0 CORE inode: INO: cnt:2 total:2 a:0x1b3efc0 len:56 a:0x1b3f060 len:96 INODE: #regs:2 ino:0x1600015ed flags:0x1 dsize:0 CORE inode: INO: cnt:2 total:2 a:0x1b3f0d0 len:56 a:0x1b3f170 len:96 INODE: #regs:2 ino:0xd000925c flags:0x1 dsize:0 CORE inode: INO: cnt:2 total:2 a:0x1b3f1e0 len:56 a:0x1b3f280 len:96 INODE: #regs:2 ino:0x30008f81 flags:0x1 dsize:0 CORE inode: INO: cnt:2 total:2 a:0x1b3f2f0 len:56 a:0x1b3f390 len:96 INODE: #regs:2 ino:0x70c93aac flags:0x1 dsize:0 CORE inode: INO: cnt:2 total:2 a:0x1b3f400 len:56 a:0x1b3f4a0 len:96 INODE: #regs:2 ino:0x2000689e flags:0x1 dsize:0 CORE inode: INO: cnt:2 total:2 a:0x1b3f510 len:56 a:0x1b3f5b0 len:96 INODE: #regs:2 ino:0xd000925a flags:0x1 dsize:0 CORE inode: INO: cnt:2 total:2 a:0x1b3f620 len:56 a:0x1b3f6c0 len:96 INODE: #regs:2 ino:0x30008f85 flags:0x1 dsize:0 CORE inode: INO: cnt:2 total:2 a:0x1b3f730 len:56 a:0x1b3f7d0 len:96 INODE: #regs:2 ino:0xb0006f6d flags:0x1 dsize:0 CORE inode: INO: cnt:2 total:2 a:0x1b3f840 len:56 a:0x1b3f8e0 len:96 INODE: #regs:2 ino:0x100f0fbd flags:0x1 dsize:0 CORE inode: INO: cnt:2 total:2 a:0x1b3f950 len:56 a:0x1b3f9f0 len:96 INODE: #regs:2 ino:0x150004315 flags:0x1 dsize:0 CORE inode: INO: cnt:2 total:2 a:0x1b3fa60 len:56 a:0x1b3fb00 len:96 INODE: #regs:2 ino:0xb0000964 flags:0x1 dsize:0 CORE inode: INO: cnt:2 total:2 a:0x1b3fb70 len:56 a:0x1b3fc10 len:96 INODE: #regs:2 ino:0x120004a41 flags:0x1 dsize:0 CORE inode: INO: cnt:2 total:2 a:0x1b3fc80 len:56 a:0x1b3fd20 len:96 INODE: #regs:2 ino:0x67586862 flags:0x1 dsize:0 CORE inode: INO: cnt:2 total:2 a:0x1b3fd90 len:56 a:0x1b3fe30 len:96 INODE: #regs:2 ino:0xf00006dd flags:0x1 dsize:0 CORE inode: INO: cnt:2 total:2 a:0x1b3fea0 len:56 a:0x1b3ff40 len:96 INODE: #regs:2 ino:0x30008f83 flags:0x1 dsize:0 CORE inode: INO: cnt:2 total:2 a:0x1b3ffb0 len:56 a:0x1b40050 len:96 INODE: #regs:2 ino:0x1a001112d flags:0x1 dsize:0 CORE inode: INO: cnt:2 total:2 a:0x1b400c0 len:56 a:0x1b40160 len:96 INODE: #regs:2 ino:0x30008f87 flags:0x1 dsize:0 CORE inode: INO: cnt:2 total:2 a:0x1b401d0 len:56 a:0x1b40270 len:96 INODE: #regs:2 ino:0xc0001132 flags:0x1 dsize:0 CORE inode: INO: cnt:2 total:2 a:0x1b402e0 len:56 a:0x1b40380 len:96 INODE: #regs:2 ino:0xf0039bc3 flags:0x1 dsize:0 CORE inode: INO: cnt:2 total:2 a:0x1b403f0 len:56 a:0x1b40490 len:96 INODE: #regs:2 ino:0x70c93ab2 flags:0x1 dsize:0 CORE inode: INO: cnt:2 total:2 a:0x1b40500 len:56 a:0x1b405a0 len:96 INODE: #regs:2 ino:0x6758685e flags:0x1 dsize:0 CORE inode: INO: cnt:2 total:2 a:0x1b40610 len:56 a:0x1b406b0 len:96 INODE: #regs:2 ino:0x70c93aae flags:0x1 dsize:0 CORE inode: INO: cnt:2 total:2 a:0x1b40720 len:56 a:0x1b407c0 len:96 INODE: #regs:2 ino:0x1b001a710 flags:0x1 dsize:0 CORE inode: INO: cnt:2 total:2 a:0x1b40830 len:56 a:0x1b408d0 len:96 INODE: #regs:2 ino:0x30008f8b flags:0x1 dsize:0 CORE inode: INO: cnt:2 total:2 a:0x1b40940 len:56 a:0x1b409e0 len:96 INODE: #regs:2 ino:0x91478f94 flags:0x1 dsize:0 CORE inode: INO: cnt:2 total:2 a:0x1b40a50 len:56 a:0x1b40af0 len:96 INODE: #regs:2 ino:0x200068ae flags:0x1 dsize:0 CORE inode: INO: cnt:2 total:2 a:0x1b40b60 len:56 a:0x1b40c00 len:96 INODE: #regs:2 ino:0x200068ac flags:0x1 dsize:0 CORE inode: INO: cnt:2 total:2 a:0x1b40c70 len:56 a:0x1b40d10 len:96 INODE: #regs:2 ino:0x10027d211 flags:0x1 dsize:0 CORE inode: INO: cnt:2 total:2 a:0x1b40d80 len:56 a:0x1b40e20 len:96 INODE: #regs:2 ino:0x100f0fb1 flags:0x1 dsize:0 CORE inode: INO: cnt:2 total:2 a:0x1b40e90 len:56 a:0x1b40f30 len:96 INODE: #regs:2 ino:0x200068a2 flags:0x1 dsize:0 CORE inode: INO: cnt:2 total:2 a:0x1b40fa0 len:56 a:0x1b41040 len:96 INODE: #regs:2 ino:0x200068a6 flags:0x1 dsize:0 CORE inode: INO: cnt:2 total:2 a:0x1b410b0 len:56 a:0x1b41150 len:96 INODE: #regs:2 ino:0x70c93ab0 flags:0x1 dsize:0 CORE inode: INO: cnt:2 total:2 a:0x1b411c0 len:56 a:0x1b41260 len:96 INODE: #regs:2 ino:0x500f38c5 flags:0x1 dsize:0 CORE inode: INO: cnt:2 total:2 a:0x1b412d0 len:56 a:0x1b41370 len:96 INODE: #regs:2 ino:0x200068a4 flags:0x1 dsize:0 CORE inode: INO: cnt:2 total:2 a:0x1b413e0 len:56 a:0x1b41480 len:96 INODE: #regs:2 ino:0x91478f89 flags:0x1 dsize:0 CORE inode: INO: cnt:2 total:2 a:0x1b414f0 len:56 a:0x1b41590 len:96 INODE: #regs:2 ino:0x200068aa flags:0x1 dsize:0 CORE inode: INO: cnt:2 total:2 a:0x1b41600 len:56 a:0x1b416a0 len:96 INODE: #regs:2 ino:0x30008f89 flags:0x1 dsize:0 CORE inode: INO: cnt:2 total:2 a:0x1b41710 len:56 a:0x1b417b0 len:96 INODE: #regs:2 ino:0x500f38c1 flags:0x1 dsize:0 CORE inode: INO: cnt:2 total:2 a:0x1b41820 len:56 a:0x1b418c0 len:96 INODE: #regs:2 ino:0x30008fa1 flags:0x1 dsize:0 CORE inode: INO: cnt:2 total:2 a:0x1b41930 len:56 a:0x1b419d0 len:96 INODE: #regs:2 ino:0x478f2 flags:0x1 dsize:0 CORE inode: INO: cnt:2 total:2 a:0x1b41a40 len:56 a:0x1b41ae0 len:96 INODE: #regs:2 ino:0x100f0fb7 flags:0x1 dsize:0 CORE inode: INO: cnt:2 total:2 a:0x1b41b50 len:56 a:0x1b41bf0 len:96 INODE: #regs:2 ino:0xa0017c5f flags:0x1 dsize:0 CORE inode: INO: cnt:2 total:2 a:0x1b41c60 len:56 a:0x1b41d00 len:96 INODE: #regs:2 ino:0x100f0fb5 flags:0x1 dsize:0 CORE inode: INO: cnt:2 total:2 a:0x1b41d70 len:56 a:0x1b41e10 len:96 INODE: #regs:2 ino:0x1300187fb flags:0x1 dsize:0 CORE inode: INO: cnt:2 total:2 a:0x1b41e80 len:56 a:0x1b41f20 len:96 INODE: #regs:2 ino:0x500f38c3 flags:0x1 dsize:0 CORE inode: INO: cnt:2 total:2 a:0x1b41f90 len:56 a:0x1b42030 len:96 INODE: #regs:2 ino:0x1f003b839 flags:0x1 dsize:0 CORE inode: INO: cnt:2 total:2 a:0x1b420a0 len:56 a:0x1b42140 len:96 INODE: #regs:2 ino:0x14000246b flags:0x1 dsize:0 CORE inode: INO: cnt:2 total:2 a:0x1b421b0 len:56 a:0x1b42250 len:96 INODE: #regs:2 ino:0x6005282b flags:0x1 dsize:0 CORE inode: INO: cnt:2 total:2 a:0x1b422c0 len:56 a:0x1b42360 len:96 INODE: #regs:2 ino:0x200068a8 flags:0x1 dsize:0 CORE inode: INO: cnt:2 total:2 a:0x1b423d0 len:56 a:0x1b42470 len:96 INODE: #regs:2 ino:0x100f0fb3 flags:0x1 dsize:0 CORE inode: INO: cnt:2 total:2 a:0x1b424e0 len:56 a:0x1b42580 len:96 INODE: #regs:2 ino:0x700060fc flags:0x1 dsize:0 CORE inode: INO: cnt:2 total:2 a:0x1b425f0 len:56 a:0x1b42690 len:96 INODE: #regs:2 ino:0x170002d17 flags:0x1 dsize:0 CORE inode: INO: cnt:2 total:2 a:0x1b42700 len:56 a:0x1b427a0 len:96 INODE: #regs:2 ino:0x100f0fb9 flags:0x1 dsize:0 CORE inode: INO: cnt:2 total:2 a:0x1b42810 len:56 a:0x1b428b0 len:96 INODE: #regs:2 ino:0x110002df8 flags:0x1 dsize:0 CORE inode: INO: cnt:2 total:2 a:0x1b42920 len:56 a:0x1b429c0 len:96 INODE: #regs:2 ino:0x87534f84 flags:0x1 dsize:0 CORE inode:
LOG REC AT LSN cycle 151 block 404576 (0x97, 0x62c60) ============================================================================ TRANS: tid:0x354dba0a #items:2 trans:0x354dba0a q:0x1b24870 INO: cnt:2 total:2 a:0x1b42920 len:56 a:0x1b429c0 len:96 INODE: #regs:2 ino:0x91478f94 flags:0x1 dsize:0 CORE inode: ---------
(None of the filesystems are mounted with "noatime")
Regards, Ulrich
--Quanah