Fujitsu BS2OSD manual New functions in BS2000/OSD V6.0B with, Correction Package 2/2006

	2.16 New functions in BS2000/OSD V6.0B with
	Correction Package 2/2006
	2.16.1 Autonomous, dynamic control of I/O resources (IORM)
*4	The new utility program IORM facilitates autonomous, dynamic
*4	control of the I/O resources, devices, controllers, channels
*4	(type S and type FC) and paths. Both S and SX servers are
*4	supported in native and in VM2000 operation.
*4	The following functions are implemented:
*4	- IOPT:	I/O priority control for tasks with competing access
*4		to one device (I/O Priority Handling for Tasks)
*4	- DPAV:	Dynamic I/O load distribution for S server disks
*4		on the FC channel (Dynamic Parallel Access Volume)
*4	- DDAL	Optimized load distribution in CentricStor operation
*4		(Dynamic Device Allocation)
*4	- IOLVM:	Limiting of I/O throughput for single VM2000 guest
*4		systems (I/O-Limit for Virtual Machines)
*4	- TCOM:	Adapting the compression for LTO devices
*4		(Tape Compression)
*4	The IOPT, DPAV and IOLVM functions control disks, the DDAL and
*4	the TCOM functions control tape devices.
*4	IORM links itself into the BS2000 I/O system and collects I/O
*4	data to determine the I/O resources utilization. IORM also
*4	periodically checks whether intervention in the I/O operation
*4	is required.
*4	The values set for intervention such as thresholds, selection of
*4	devices to be monitored or I/O priorities can be passed to IORM
*4	in the form of a parameter file or in dialog.
*4	IORM has a HELP function that outputs all permitted statements
*4	together with their syntax.
*4	You will find a detailed description in the SYSRME.IORM.060.E
*4	file or in the utilities manual.
*4	I/O-Priority control for tasks (IOPT)
*4	I/O-intensive but relatively unimportant applications can
*4	obstruct other, more important applications if the I/Os are on
*4	the same device or on devices on the same controller, path,
*4	port or channel.
*4	Three I/O priorities, low, medium and high, were therefore
*4	introduced for IORM.
*4	If the IOPT function is activated in IORM (IOPT_SET_ON=YES
*4	statement), IORM applies brakes to the tasks with low and medium
*4	priorities by assigning time penalties if these tasks hinder
*4	tasks with higher priorities.
*4	IORM does not affect tasks with I/O priority high.
*4	I/Os via FDDRL, ARCHIVE, VOLIN or PAGING are also not braked.

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