Quantum 6-00360-15 manual Rtio Upper Bound

Appendix D Quality of Service Guide

Configuration

Name	Description	Default
RtiosReserve	Amount of reserve in I/Os/sec	Equivalent to
	from the maximum allowed for	1MB/sec
	non-real-time I/Os. Must be
	greater than the equivalent to
	1MB/sec or the amount that can
	be transferred to a single stripe
	line.
RtmbReserve	Amount to reserve in MB/sec	Must be
	from the maximum allowed for	greater than 1.
	non-real-time I/O.	1MB/sec
RtTokenTimeout	Time in seconds to wait for clients	2 seconds
	to respond to a token callback.

RTIO Upper Bound

The limit will be specified in terms of I/Os per second (parameter Rtios) or in terms of MB/sec (parameter Rtmb). Case is not sensitive. Note that I/Os per second are I/Os of any size to the disk subsystem. Either or both may be specified. If both are specified, the lower limit is used to throttle

I/O. If neither is specified, no real-time I/O is available on the stripe group. These parameters are applied to a stripe group definition.

[StripeGroup MyStripeGroup]

Rtios 2048

Rtmb 10

The above example specifies that the storage system can support a maximum of 2048 I/Os per second at any instant, aggregate among all the clients, or 10 MB/sec, whichever is lower.

Most real-time I/O requests will be a stripe line at a time to maximize performance. Non-real-time I/Os will be a minimum of a file system block size.

StorNext 3.1.3 Installation Guide 139