User's Manual

Appendix D Quality of Service Guide
Configuration
StorNext 3.1.3 Installation Guide 139
RTIO Upper Bound 4
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.
RtiosReserve
Amount of reserve in I/Os/sec
from the maximum allowed for
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.
Equivalent to
1MB/sec
RtmbReserve
Amount to reserve in MB/sec
from the maximum allowed for
non-real-time I/O.
Must be
greater than 1.
1MB/sec
RtTokenTimeout
Time in seconds to wait for clients
to respond to a token callback.
2 seconds
Name Description Default