Linux 4.2 Will Tweak The CFQ Scheduler For SSDs To Offer Better Performance

[phoronix]

Phoronix: Linux 4.2 Will Tweak The CFQ Scheduler For SSDs To Offer Better Performance

The Linux 4.2 kernel will make the CFQ I/O scheduler default to its IOPS mode when on solid-state drives, which should boost performance...

http://www.phoronix.com/scan.php?page=news_item&px=CFQ-IO-Scheduler-IOPS-Linux-4.2

[dimko]

Very Interesting, thank you!

[roberth]

Is this option available and ready to use in 3.16?

[chilek]

Is this option available and ready to use in 3.16?

Try the following command:

find /sys -type f -name slice_idle

and then:

echo "0" >file_name_found_in_first_command_which_applies_to_your_ssd

so we don't need to wait for 4.2 kernel to test it.

[roberth]

Try the following command:

find /sys -type f -name slice_idle

and then:

echo "0" >file_name_found_in_first_command_which_applies_to_your_ssd

so we don't need to wait for 4.2 kernel to test it.

[COLOR=#000000][roberth@Desktop ~]$ sudo echo "0" > /sys/devices/pci0000:00/0000:00:1f.2/ata5/host4/target4:0:0/4:0:0:0/block/sda/queue/iosched/slice_idle[/COLOR]  
 An error occurred while redirecting file '/sys/devices/pci0000:00/0000:00:1f.2/ata5/host4/target4:0:0/4:0:0:0/block/sda/queue/iosched/slice_idle' open: Permission denied

EDIT: Okay maybe not use sudo for that. But how do I make it an udev rule so it gets renable on restarts?

[AnAkIn]

If the BFQ patches would be merged, it would probably be even better, but that's unfortunately not going to happen anytime soon :/

[chilek]

EDIT: Okay maybe not use sudo for that. But how do I make it an udev rule so it gets renable on restarts?

Actually It depends on distribution which you use.
In fedora you can create /etc/rc.d/rc.local file as executable script and put those lines there.

[eydee]

Is this an improvement compared to other operating systems or catching up?

[chilek]

Is this an improvement compared to other operating systems or catching up?

It's some kind of autotuning which should be done manually in kernels released so far.

[gens]

"Note that this mode switching takes effect only for group scheduling. For non-cgroup users nothing should change."

not for auto process grouping ?