Unity Design: Midrange Sizer for Unity Flashcards
What are the 6 inputs that should be gathered to properly size and design Unity?
server information
workload characterization
capacity
replication
tiering
skew
What makes up the server information in Unity sizing?
planned server consolidation
protocols
types of servers (physical/virtual)
OS
What makes up the workload characterization in Unity sizing?
IO type (block/file)
block size
IOPS
throughput
What makes up the capacity in Unity sizing?
current capacity
anticipated growth
What makes up the replication in Unity sizing?
requirement for local or remote replication
What makes up the skew in Unity sizing?
changing patterns of active data or hot blocks relative to overall storage capacity
What do maximum performance limits depend on for Unity sizing?
protocols used
IO size and mix
access pattern
What is the importance of performance limits in Unity sizing?
can help optimize in place systems and plan port capacity for proposed system
What is important to know about performance limits for Unity?
response times at the upper limits may be unacceptable because CPUs may be at saturation point
What information do you need to optimize port performance for Unity?
sustained per port IOPS (for small block mixed random workloads)
sustained per port MB/s (for large blocked mixed sequential workloads)
What are port utilization recommendations for Unity sizing?
use front end ports and cores for optimal performance
if iSCSI on Unity XT 380 - use CNA ports on system - can be used for iSCSI offload
What is the difference in port performance for Unity XT 380 vs higher models?
higher performing models have mezzanine cards instead of CNA ports
cards enable higher performance than CNA ports
What port load balancing features does Unity have?
multi-core architecture and port-to-core affinity
How is port-to-core affinity implemented in Unity?
associating IO ports with a core thereby load balancing port IO across multiple cores/maximizing system potential
What are the performance recommendations for port balancing on Unity?
configure system with as many front end ports as possible
if limited number of front end open switch ports use a single port
multi-core architecture optimizes configuration by a round robin load balancing across cores
What is the performance of a Unity with a one port switch to SAN configuration?
with workload from a single port running on one core due to port-to-core affinity CPU utilization stays at 80%
other cores in system spike one by one because they help in round robin load balancing
What is the performance of a Unity with a four port switch to SAN configuration?
more cores are dedicated to handling IO from the additional ports - CPU utilization stays below 80%
What is the performance of a Unity with a eight port switch to SAN configuration?
all the cores handle the IO - CPU utilization stay below 80% - maximum efficiency
How do you assess if the drives are a bottleneck for Unity sizing?
check the sustained per drive IOPS
What are the acceptable sustained per drive IOPS for each drive type assuming small block mixed random workloads?
NL-SAS - less than 150
SAS 10K - less than 250
SAS 15K - less than 350
SAS Flash - less than 20,000
What might be the probable bottleneck/solution if the reported bandwidth on a solution is ~110MB/s and its multiples?
1GbE network port
use more ports/use 10GbE
What might be the probable bottleneck/solution if the reported bandwidth on a solution is ~750MB/s and its multiples?
8Gb FC port
use more ports/use 16Gb FC
What might be the probable bottleneck/solution if the reported bandwidth on a solution is ~1,100MB/s and its multiples?
10GbE network port
use more ports
What might be the probable bottleneck/solution if the reported bandwidth on a solution is ~1,500MB/s and its multiples?
15Gb FC port
use more ports
