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 basis. 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 and it can be considered as a queue ID. For example multiple partitions in the same harddisk will share the same queue and so tuning one partition will be like tuning the whole HD.
−rr_latset the max latency that the I/O scheduler will provide on each read.
−ww_latset the max latency that the I/O scheduler will provide on each write.
−bb_maxmax coalescing factor allowed on writes when there are reads pending in the queue.
−hhelp.
−vversion.