btrfs with discard option has terrible performance
Affects | Status | Importance | Assigned to | Milestone | |
---|---|---|---|---|---|
linux (Ubuntu) |
Confirmed
|
Undecided
|
Unassigned |
Bug Description
Enabling 'discard' for btrfs on an SSD results in a substantial performance degradation, possibly related to fsync(). This is very noticable when running 'apt-get upgrade', and the test suggested in the link below went from 12 seconds without discard to 45 seconds with discard enabled.
ProblemType: Bug
DistroRelease: Ubuntu 11.04
Package: linux-image (not installed)
ProcVersionSign
Uname: Linux 2.6.38-8-generic x86_64
AlsaVersion: Advanced Linux Sound Architecture Driver Version 1.0.23.
Architecture: amd64
ArecordDevices:
**** List of CAPTURE Hardware Devices ****
card 0: Intel [HDA Intel], device 0: STAC92xx Analog [STAC92xx Analog]
Subdevices: 1/1
Subdevice #0: subdevice #0
AudioDevicesInUse:
USER PID ACCESS COMMAND
/dev/snd/
CRDA: Error: [Errno 2] No such file or directory
Card0.Amixer.info:
Card hw:0 'Intel'/'HDA Intel at 0xd4500000 irq 45'
Mixer name : 'Intel Cantiga HDMI'
Components : 'HDA:111d7605,
Controls : 18
Simple ctrls : 10
Date: Tue Jun 14 09:20:35 2011
HibernationDevice: RESUME=
InstallationMedia: Ubuntu 10.10 "Maverick Meerkat" - Release amd64 (20101007)
MachineType: Hewlett-Packard HP Pavilion dm1 Notebook PC
ProcEnviron:
LANGUAGE=en_US:en
PATH=(custom, user)
LANG=en_US.UTF-8
SHELL=/bin/zsh
ProcKernelCmdLine: BOOT_IMAGE=
RelatedPackageV
linux-
linux-
linux-firmware 1.52
SourcePackage: linux
UpgradeStatus: Upgraded to natty on 2011-05-04 (40 days ago)
dmi.bios.date: 09/03/2009
dmi.bios.vendor: Hewlett-Packard
dmi.bios.version: F.02
dmi.board.
dmi.board.name: 3663
dmi.board.vendor: Quanta
dmi.board.version: 49.0A
dmi.chassis.type: 10
dmi.chassis.vendor: Quanta
dmi.chassis.
dmi.modalias: dmi:bvnHewlett-
dmi.product.name: HP Pavilion dm1 Notebook PC
dmi.product.
dmi.sys.vendor: Hewlett-Packard
Changed in linux (Ubuntu): | |
status: | New → Confirmed |