Hide Forgot
Description of problem: Poor disk performance # hdparm -t /dev/sda /dev/sda: Timing buffered disk reads: 82 MB in 3.41 seconds = 24.08 MB/sec [root@gpslap37 4.8.8-300.fc25.x86_64]# hdparm -t /dev/sda /dev/sda: Timing buffered disk reads: 92 MB in 3.22 seconds = 28.61 MB/sec Version-Release number of selected component (if applicable): 4.8.8-300.fc25.x86_64 How reproducible: Always Steps to Reproduce: 1. Boot laptop on standard kernel 2. Run hdparm as above 3. Actual results: < 30MB/sec Expected results: SSD performance Additional info: Performance has been the same for several Fedora versions dmesg | grep ata [ 0.000000] BIOS-e820: [mem 0x000000009cfbf000-0x000000009cffefff] ACPI data [ 0.000000] Memory: 8065340K/8302960K available (8221K kernel code, 1416K rwdata, 3340K rodata, 1608K init, 1520K bss, 237620K reserved, 0K cma-reserved) [ 0.333526] ACPI : EC: GPE = 0xa, I/O: command/status = 0x66, data = 0x62 [ 0.353761] libata version 3.00 loaded. [ 0.940691] ata1: DUMMY [ 0.940695] ata2: SATA max UDMA/133 abar m2048@0xb0523000 port 0xb0523180 irq 41 [ 1.246068] ata2: SATA link up 6.0 Gbps (SStatus 133 SControl 300) [ 1.248110] ata2.00: ACPI cmd ef/10:09:00:00:00:b0 (SET FEATURES) succeeded [ 1.248811] ata2.00: NCQ Send/Recv Log not supported [ 1.248813] ata2.00: ATA-9: SAMSUNG MZMTE256HMHP-000L1, EXT43L0Q, max UDMA/133 [ 1.248815] ata2.00: 500118192 sectors, multi 16: LBA48 NCQ (depth 31/32), AA [ 1.249225] ata2.00: ACPI cmd ef/10:09:00:00:00:b0 (SET FEATURES) succeeded [ 1.249873] ata2.00: NCQ Send/Recv Log not supported [ 1.249977] ata2.00: configured for UDMA/133 [ 1.260848] Write protecting the kernel read-only data: 14336k [ 6.864750] EXT4-fs (dm-4): mounted filesystem with ordered data mode. Opts: (null) [ 8.873329] EXT4-fs (sda2): mounted filesystem with ordered data mode. Opts: (null) [ 8.873388] EXT4-fs (dm-6): mounted filesystem with ordered data mode. Opts: discard [ 8.902365] EXT4-fs (dm-7): mounted filesystem with ordered data mode. Opts: discard [ 1481.118901] ata2: SATA link up 6.0 Gbps (SStatus 133 SControl 300) [ 1481.120914] ata2.00: ACPI cmd ef/10:09:00:00:00:b0 (SET FEATURES) succeeded [ 1481.121569] ata2.00: NCQ Send/Recv Log not supported [ 1481.122010] ata2.00: ACPI cmd ef/10:09:00:00:00:b0 (SET FEATURES) succeeded [ 1481.122616] ata2.00: NCQ Send/Recv Log not supported [ 1481.122668] ata2.00: configured for UDMA/133 # dmesg | grep ahci [ 0.939682] ahci 0000:00:1f.2: version 3.0 [ 0.939923] ahci 0000:00:1f.2: AHCI 0001.0300 32 slots 1 ports 6 Gbps 0x2 impl SATA mode [ 0.939926] ahci 0000:00:1f.2: flags: 64bit ncq pm led clo only pio slum part deso sadm sds apst
*********** MASS BUG UPDATE ************** We apologize for the inconvenience. There is a large number of bugs to go through and several of them have gone stale. Due to this, we are doing a mass bug update across all of the Fedora 25 kernel bugs. Fedora 25 has now been rebased to 4.9.3-200.fc25. Please test this kernel update (or newer) and let us know if you issue has been resolved or if it is still present with the newer kernel. If you have moved on to Fedora 26, and are still experiencing this issue, please change the version to Fedora 26. If you experience different issues, please open a new bug report for those.
Seems much better? # for i in 1 2 3 4 5 6 > do > hdparm -t /dev/sda > sleep 5 > done /dev/sda: Timing buffered disk reads: 862 MB in 3.00 seconds = 287.32 MB/sec /dev/sda: Timing buffered disk reads: 990 MB in 3.00 seconds = 329.72 MB/sec /dev/sda: Timing buffered disk reads: 1082 MB in 3.00 seconds = 360.28 MB/sec /dev/sda: Timing buffered disk reads: 1086 MB in 3.00 seconds = 361.90 MB/sec /dev/sda: Timing buffered disk reads: 1086 MB in 3.00 seconds = 361.57 MB/sec /dev/sda: Timing buffered disk reads: 1084 MB in 3.00 seconds = 360.88 MB/sec [root@zinc ~]# hdparm -t /dev/sda /dev/sda: Timing buffered disk reads: 936 MB in 3.00 seconds = 311.87 MB/sec