elvtune — I/O elevator tuner
elvtune
[ −r
r_lat ] [ −w
w_lat ] [ −b
b_max ] device...
elvtune
−h
elvtune
−v
elvtune allows to tune the I/O elevator per blockdevice queue. The tuning can be safely done at runtime. Tuning the elevator means being able to change disk performance and interactiveness. In the output of elvtune the address of the queue tuned will be shown; it can be considered as a queue ID. Multiple partitions on the same harddisk will share the same queue and so tuning one partition will be like tuning the whole HD.
−rr_lat
Set the maximum latency that the I/O scheduler will provide on each read.
−ww_lat
Set the maximum latency that the I/O scheduler will provide on each write.
−bb_max
Set the maximum coalescing factor allowed on writes when there are reads pending in the queue.
−h
Display help text and exit.
−v
Display version information and exit.