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Edit File: 40-elevator.rules
# We aren't adding devices skip the elevator check ACTION!="add", GOTO="sched_out" SUBSYSTEM!="block", GOTO="sched_out" ENV{DEVTYPE}!="disk", GOTO="sched_out" # Technically, dm-multipath can be configured to use an I/O scheduler. # However, there are races between the 'add' uevent and the linking in # of the queue/scheduler sysfs file. For now, just skip dm- devices. KERNEL=="dm-*|md*", GOTO="sched_out" # Skip bio-based devices, which don't support an I/O scheduler. ATTR{queue/scheduler}=="none", GOTO="sched_out" # If elevator= is specified on the kernel command line, change the # scheduler to the one specified. IMPORT{cmdline}="elevator" ENV{elevator}!="", ATTR{queue/scheduler}="$env{elevator}" LABEL="sched_out"