Figure 64 Qos; Figure 65 Copy Path Bandwidth Limit - Fujitsu ETERNUS AF250 Design Manual

1. Function
Stable Operation via Load Control
Linking with ETERNUS SF Storage Cruiser significantly reduces the operation workload on the system administra-
tor when applying the QoS function because performance designing and tuning are automatically performed.

Figure 64 QoS

Server A Server B
Low priority High priority
ETERNUS AF
●
REC Bandwidth Limit (Remote Copy QoS)
A bandwidth upper limit can be set for each copy path in the remote copy session.
Even if a specific path fails, the line bandwidth can be maintained without centralizing the load to other paths.
The bandwidth limit can be specified in increments of Mbit/s.

Figure 65 Copy Path Bandwidth Limit

Normal operation
REC path setting
Effective line speed
400Mbit/s
RA
RA
ETERNUS AF
When QoS is not applied
Processing requests
from A increase
Server A
Required performance for A
Affects the performance of B
Server B
Required performance for B
I/O performance
Because the workload for A, which has a low
priority, significantly increases, the required
performance for B cannot be maintained
1 path fails
QoS
200Mbit/s
200Mbit/s
200Mbit/s
200Mbit/s
FUJITSU Storage ETERNUS AF250 S2, ETERNUS AF250 All-Flash Arrays Design Guide (Basic)
Copyright 2019 FUJITSU LIMITED
When QoS is applied
Server A
Server B
High
I/O performance
Because the workload for A is lower than
the upper limit, the workload for B, which has
a high priority, can be reduced
Even if a specific path
fails, steady load can
be maintained
REC path setting
Effective line speed
QoS
400Mbit/s
Failure
200Mbit/s
RA
200Mbit/s
RA
200Mbit/s
ETERNUS AF
103
The workload does not exceed
the upper limit even when
processing requests from A
increase
Workload upper limit for A
Workload upper limit for B
High
P3AG-1822-09ENZ0