accelerate with ibm storage: ds8000 easy tier · hotspot analysis smart data placement ... easy...

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Accelerate with IBM Storage:

DS8000 Easy Tier

Brian Sherman

Paul Spagnolo

IBM Washington Systems Center


Washington Systems Center - Storage

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Recent Webinars:Dec 12th IBM DS8000 R8.3 DSGUI Live Demo

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Oct10th z14 IO and Infrastructure Modernization

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Upcoming Webinars:

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Washington Systems Center – Storage

3

•Customer demonstrations (IBM CTS and BP)

•Business Resiliency with IBM Copy Services Manager Test Drive

•DS8880 GUI Configuration Test Drive

•Proof of Concepts

•Bandwidth Studies

•DS8000 Global Mirror Bandwidth needed your RPO requirements

•Transparent Cloud Tiering (TCT) Analysis

•Estimated CPU Savings with TCT (DS8000 and TS7700)



Write

Disk

Anatomy of an I/O Operation

4

Data

Read Cache Hit

Cache

Data

Data

DS8000

Data Data

Data

Read Miss

Data

Data



Overview

5

• Easy Tier provides automatic volume management capabilities

• Sub-volume drive tiering

• Manual command based volume relocation

• Automated drive utilization rebalancing to remove hot spots or populate new, empty ranks

• To Manage Easy Tier the DS8000 provides

• A command line interface and a GUI for setup and management

• Storage Tier Advisor Tool (STAT) for I/O analysis and projected benefits (legacy)

• Integrated Easy Tier reporting (as of R8.3)

• Easy Tier is a no-charge licensed advanced function for the DS8700/DS8800/DS8870/DS8880

• Supported by all server platforms with no additional software or host configuration

• No license is required to “monitor” and run STAT tool (described later)

• Easy Tier enabled by default as of R8.2



Cost versus Performance

6

Cost P

er G

iga

byte

Performance

High

Performance

Flash/SSD

High

Performance

Enterprise Drives

Low Performance

Nearline Drives

High Capacity

Flash



Configuration Optimization versus Performance Improvement

7

• Easy Tier is not application aware and it is entirely possible that manual data

placement could provide more application specific performance improvements

• The majority of storage administrators do not have the skills nor the time to do this well

even if they fully understood the details of each application

• The objective of Easy Tier is to optimize the usage of a particular environment

by placing and distributing data appropriately on the underlying storage media

without expert input and manual intervention – we’re trying to make it EASY

• By doing this at a granular sub-volume level it enables this to be done efficiently without

making changes in the volume configuration or application data layout

• Data movement and placement is based on historical data access patterns



Easy Tier Processing Cycle

8

DS8700

➢Performance data collected

every 5 minutes

➢Data collected is for rank

activity not I/O from hosts

➢Workload analysis

performed at various

intervals – 5 minutes, ~ 6

hours and ~ 24 hours

➢Extents categorized

based on small block I/O

activity

➢Can immediate promote

an extent if necessary

➢Statistics maintained for

seven days

➢Movement of extents

scheduled

➢Cost benefit analysis to

ensure excessive movement is

avoided

Continuous

Workload

Monitoring

Workload

Hotspot

Analysis

Smart

Data

Placement



Easy Tier Data Collection

9

• Easy Tier regularly collects backend performance data for each extent on the DS8000 every 5 minutes

• Not host I/O

• This activity is broken down by reads and writes & large block I/O and small block I/O for the analysis code to evaluate which data should be moved

• Large block I/Os are those which are basically a full track in size

• Easy Tier considers the small I/O when looking at prioritizing the extents to be moved.

• Any tracks that are staged as full tracks in track mode for read misses will therefore not be considered in this decision criteria – these usually are a result of sequential access patterns

• Large I/Os are considered to evaluate whether ranks or device adapters may become overloaded by moving extents to Flash/SSDs



Performance Metrics

10

• Easy Tier continually monitors the back end rank utilization and

records the following statistics for each active extent

• Reads and writes

• Small block I/O

• Large block I/O

• Latency

• I/O rate

• Data transferred



Easy Tier – Support for High Capacity Flash

• High capacity flash is considered a unique tier within Easy Tier

• Separate tier from high performance flash tier

• High performance flash are 400, 800 1600 and 3200 GB

• High capacity flash are 3800 GB (and higher)

• Easy Tier is a three tier architecture

• Tier 0 is a high performance tier and will contain as much workload as possible

• Tier 2 is a quiet capacity tier intended to contain idle or near idle workload

• Tier 1 contains the rest of the workload

• DS8000 will only allow a maximum of 3 tiers in a storage pool (i.e., no 4

tier storage pools)

• DS8000 will not allow high performance flash, high capacity flash, enterprise HDD

and nearline HDD in the same storage pool

• Legacy SSD technology drives are considered to be in the high performance flash

tier (no change from before)

11



DS8880 Storage Pools Options (3 tier maximum in a single storage pool)

12



DS8000 Virtualization Concepts

Disk

Storage Pool (CKD/FB)

DS8000 Server 0(Cluster 0)

DS8000 Server 1(Cluster 1)

Storage Pool

27 Extents

9 Extents

9 Extents

3 Extents

Logical

Volumes

Array

Site

Managed Array (RAID-5/6/10)

13



Heat and Skew

14

• Hot data

• Hot data is simply extents that have more I/O workload,

relatively speaking, when compared to other extents within the

storage pool and tier

• Cold data

• Cold data either has low (or no) I/O workload. Cold data

would not benefit from a higher tier and thus is not promoted

and is considered for demotion

• Warm data

• Warm data is the rest of the workload that is not considered

hot or cold. Warm data could be promoted – but that would

depend on the workload level and available resources

• Skew

• Highly skewed workload has a small number of hot extents

• Low skewed workload has a more even distribution of

workload to extents



Workload Skew

15



Workload Skew

16

Low skew –

about 65% of

I/O is to 40%

of disk

extents



Workload Skew

17

High skew –

about 90% of

I/O is to 8%

of disk

extents



Easy Tier Functions by Release

18

Introduced By Tier Support Auto Data Relocation Manual Data Relocation Comments

DS8700 (R5.1) Two tier

SSD+ENT / SSD+NL

• Promotion and swap • Pool merge

• Volume migration

• Base Easy Tier functionality

DS8700 (R6.1)

DS8800 (R6.1)

Any two tier

SSD+ENT, SSD+NL

ENT+NL

• Warm demotion and cold demotion

• Auto rebalance (hybrid pool only)

• Manual capacity rebalance

• Rank depopulation

• Any two tier support

• Better agility

• Storage admin features

DS8700 (R6.2)

DS8800 (R6.2)

Any three tier • Three tier support

• Auto rebalance homogeneous pool

• Three tier support

• Improved SSD utilization

• Capable of full system auto

rebalance for performance

DS8870 (R7.0) Any three tier • Encryption support

DS8870 (R7.1) Easy Tier directive data

placement

Easy Tier Heat Map

Transfer

• Allows storage administrator to control data

placement via CLI

• Provides directive data placement API to

enable SW integration solutions

• Learning data capture and apply

• Storage Administrator

interface to direct data

placement

• Easy Heat Map Transfer for

replication

DS8870 (R7.3) Easy Tier on High

Performance Flash

• Recognize and support high performance

flash modules as Tier 0

DS8870 (R7.4) Easy Tier Application for

System z

Easy Tier Control

• Allow applications from z/OS to give hints of

data placement at dataset

• Allow customer control ET learning/migration

behavior at pool/volume level

• Z application hint interface to

direct data placement

• Storage Administrator

interface to allow user control

ET learning / migration

activity

DS8870 (R7.5) More replication options for

Heat Map Transfer

• Support for Metro/Global Mirror

• Integration with GDPS and CSM

• Performance optimized DR

sites in the event of a

disaster

• Full GDPS support for 3 and

4 site MGM environments

DS8880 (R8.1) Small extent support

(16 MB or 21 cylinder)

• Warm promote

• Home tier

• Automatic reserve of ET

space

DS8880 (R8.3) High capacity flash support • Easy Tier will map the different physical

media to the 3-tier architecture

• 3.8 TB flash will be treated

as a separate tier



Operating Modes

19

• Easy Tier Automatic Mode

• Promote/demote extents (sub-volume) within tiers of disk in same storage pool

• Requires multitier or hybrid storage pool to promote/demote

• North-South

• Homogeneous pool rebalancing

• Balances the load on the ranks within a given tier in an storage pool

• East-West

• Rebalance the workload when ranks (extents) are added to the storage pool

• Easy Tier Manual Mode

• Dynamic volume relocation

• Dynamic storage pool merge

• Rank depopulation

• Restripe a volume within the same pool



Easy Tier Managed Pools

20

Flash Pools Enterprise Pools Nearline Pools

Hybrid Pools

Merge pools

Easy Tier Application

• Application assisted

data placement to

designated tiers

Manual volume migration

• Change disk class

• Change RAID type

• Change RPM

• Change Striping

Easy Tier Application

Volume-based data relocation

Cross-tier data relocation

Automated intra-tier rebalance



DS8000 Easy Tier – Hybrid Storage Pool (Multiple Disk Tiers)

21

Flash Rank

Enterprise Rank

Nearline Rank

Flash Rank

Enterprise Rank

Enterprise Rank

Enterprise Rank

Enterprise Rank

Enterprise Rank

Nearline Rank

Nearline Rank Nearline Rank

Hybrid Storage Pool

Hybrid Storage Pool

Logical

Volumes

Extent on Flash drive

Extent on Enterprise drive

Extent on Nearline drive

Pro

mote

Dem

ote



Easy Tier – Automatic Mode Overview

• Extent Migration Plan built based on I/O statistics collected (heat)

• Dynamically relocates a logical volume’s extents

• Hot extents relocated to higher performance class of disk (enterprise Flash)

• Cold extents relocated to lower performance class of disk (enterprise Nearline)

• Extent level promotion/demotion requires mixed technologies in a merged storage pool

(between any two or three tiers), for example:

• HPF + HCF + Enterprise

• HCF + Nearline

• Enterprise + Nearline

• DS8000 Extent Size

• 1GiB (large) or 16 MiB (small) for FB

• 1113 cylinder (large) or 21 cylinder (small) for CKD

• Small extents were introduced on DS8880 at R8.1.1

22

Nearline Enterprise Flash/SSD



Easy Tier Automatic Mode

23

• Promote extent

• Extent promotion occurs one tier at a time

• If all three tiers are present in a hybrid pool promotion must go through intermediate (adjacent) tier

• Demote extent

• Like promotion, demotion is one tier at a time

• Auto-rebalance within the tier

• Micro-tiering

• Automatic mode works at the extent (sub-volume) level

• Opposed to manual mode which operates only on the entire volume



Easy Tier – Automatic Mode Promotion/Demotion

24

Flash /

SSD

Enterprise

10K/15K HDD

Hot ExtentsMigrate Up

Cold ExtentsMigrate Down

Nearline

7200 HDD

Hot ExtentsMigrate Up

Cold ExtentsMigrate Down

All tiers rebalance based on workload

Logical

Volume

• Optimization of backend storage

resources based on historical performance

data

• Sub-volume granularity using native

DS8000 extents for any volume type

• Flexible configurations with any

combination of drives of any size and

speed

• Easy Tier Application provides APIs for

policy and proactive actions

• Easy Tier Heat Map transfer enables

workload history to be transferred for

replication scenarios (DR, migration etc)



Easy Tier – Back-end Read Operations by Drive Class

25

144 x 1.2 TB Enterprise class drives (172.8 TB)Average I/O Rate: 14,113



Easy Tier – Back-end Read Operations by Drive Class

26

144 x 1.2 TB Enterprise class drives (172.8 TB) 88%30 x 800 GB Flash (24 TB) 12%Average I/O Rate: 29,025



Easy Tier – Back-end Disk Read Response Times by Drive Class

27

144 x 1.2 TB Enterprise class drives (172.8 TB)Average Response Time: 5.59 ms @ 14,113 IOPS



Easy Tier – Back-end Disk Read Response Times by Drive Class

28

144 x 1.2 TB Enterprise class drives (172.8 TB) 88%30 x 800 GB Flash (24 TB) 12%Weighted Average Response Time: 0.71 ms @ 29,025 IOPS



Auto Rebalance

29

Managed Storage Pool

Flash/SSD Rank

Enterprise Ranks

Hot Extents

Migrate Up

Cold Extents

Migrate Down

2

1

3

Extents migrated to

balance workload

across ranks

Rank 1 Rank 2 Rank 3

• Extents moved between ranks

of the same tier to balance

workload

• Balances rank skew due to

• Workload

• Change in resources

• Proactively avoids hot spots

• Eliminates need to manually

re-stripe extents

• Begins after 6 hours by default



Auto Rebalance

30

Managed Storage Pool

Enterprise Ranks

Hot Extents

Migrate Up

Cold Extents

Migrate Down

2

1

3

Extents migrated to

balance workload

across ranks


Flash/SSD Rank• Extents moved between ranks

of the same tier to balance

workload

• Balances rank skew due to

• Workload

• Change in resources

• Proactively avoids hot spots

• Eliminates need to manually

re-stripe extents

• Accomplished on six hour cycle



DS8000 Easy Tier - Homogeneous Disk Tier

31

Enterprise Rank

Enterprise Rank

Enterprise Rank

Enterprise Rank

Enterprise Rank

Enterprise Rank

Homogeneous Storage Pool

Homogeneous Storage Pool

Logical

Volumes

Extent on Enterprise drive

Enterprise Rank

Enterprise Rank

Enterprise Rank

Enterprise Rank

Enterprise Rank

Enterprise Rank

With Easy Tier rank rebalancing rank utilization is more aligned resulting in more even I/O performance

Enterprise Rank Enterprise Rank Enterprise Rank Enterprise Rank Enterprise Rank Enterprise Rank Enterprise Rank Enterprise Rank Enterprise Rank Enterprise Rank Enterprise Rank Enterprise Rank

Without Easy Tier Homogeneous Rebalancing rank utilization skew can provide uneven I/O performance

Enterprise Rank Enterprise Rank Enterprise Rank Enterprise Rank Enterprise Rank Enterprise Rank Enterprise Rank Enterprise Rank Enterprise Rank Enterprise Rank Enterprise Rank Enterprise Rank



Easy Tier – Homogeneous Pool Rebalancing

32

• Easy Tier will automatically rebalance within a

homogeneous storage pool

• Reduces skew and hot spots within a rank

• Extents are automatically rebalanced across ranks of the

same tier within the storage pool based on I/O and

bandwidth requirements

• Six hour cycle

hot coldRank hot cold

hot coldRank

hot

cold

Rank

Rank

New rank added to pool

After

hot coldRank hot cold

hot coldRank

hot

cold

Rank

Rank cold

cold

Natural Performance Skew

cold cold

coldcold

After



Capacity TierCapacity TierCapacity Tier

Intra-tier Rebalancing

33

Performance Tier

Pro

mo

te/

De

mo

te



Performance Gains with Homogeneous Pool Rebalancing

34



Micro-tiering

35

• Easy Tier automatic mode can also help intra-tier storage pool management

• Same class of drives but different device geometries

• Example:

• 1200 GB/10K drives with some RAID-5 some RAID-6

• 600 GB/15K + 600 GB/10K in same storage pool

• 300 GB SSD + 400 GB SSD in same storage pool

• SSD + high performance flash cards in the same storage pool

• RAID-5 + RAID-10 in same storage pool

• There is no promote/demote capability within the same drive class

• Micro-tiering is best thought of as a rebalance action

• Rebalance can occur if skew is significant

• 6 hour learning cycle

• Not driven by extent heat but rather device (rank) utilization

• Based upon performance characteristics of the rank



36

Easy Tier Volume Allocation Order

• When new logical volumes are defined in a storage pool, allocation location is

dependent on user control

• High Utilization

• High Performance

• Use the DSCLI command “chsi –ettierorder highutil | highperf” to set

DS8880 Hybrid

High Utilization High Performance

1. Enterprise tier 1. High performance flash tier

2. High capacity flash tier 2. High capacity flash tier

3. Nearline tier 3. Enterprise tier

4. High performance flash tier 4. Nearline tier

DS8880 All Flash

High Utilization High Performance

1. High capacity flash tier 1. High performance flash tier

2. High performance flash tier 2. High capacity flash tier



Easy Tier Auto Mode Summary

37



Easy Tier Auto Mode Extent Migration Définitions

38

• Promote

• Moves the hotter extents to the ranks of the target tier with available capacity. Promote occur within adjacent tiers

• Demote

• Demotes colder extents from the higher tier to the lower tier. Demote occurs within adjacent tiers

• Move

• Auto-rebalance which is also known as intra-tier rebalancing, is a capability of Easy Tier that automatically rebalances the workload across all ranks of a storage tier within a managed storage pool

• Auto-rebalance also automatically populates new ranks that were added to the pool when rebalancing the workload within a tier

• Swap

• A swap moves a “hot” extent from a lower performance disk tier to a higher disk tier while simultaneously moving a “cold” extentfrom the higher disk tier to a lower performance disk tier

• Cold Demote

• Cold demote only occurs between HDD tiers; that is, between Enterprise and Nearline disks.

• Easy Tier Automatic Mode automatically locates and demotes inactive (or cold) extents that are on a higher performance tier to its adjacent lower-cost tier. In that way, Easy Tier Automatic Mode automatically frees extents on the higher storage tier before the extents on the lower tier become hot, and then helps the system to be more responsive to new hot data

• Warm Promote

• Occurs out of cycle when an extent can be moved to a higher performance tier to provide immediate better performance

• Warm Demote

• Easy Tier Automatic Mode monitors the performance of the ranks and triggers the movement of selected extents from the higher-performance tier to the lower-performance tier

• This action is based on predefined bandwidth or IOPS overload thresholds. Easy Tier continuously ensures that the higher-performance tier does not suffer from saturation or overload conditions that might affect the overall performance in the storagepool

• RB-Swap

• A rebalance swap, like the swap, moves two extents simultaneously. In this case, both extents are within the same disk tier

• The rebalance swap is used to clear space on a cold rank so a hot extent can be moved to its place. The intent is to balance I/O workload activity within all ranks of the same tier in the storage pool



Easy Tier – Manual Mode Overview

39

• Easy Tier Manual Mode allows a user to perform the following actions:

• Dynamic Volume Migration

• User can change a logical volume’s storage technology by dynamically relocating

between storage pools

• User can change a logical volume’s extent allocation algorithm (EAM)

(e.g. can re-rotate extents within the target storage pool)

• Dynamic Storage Pool Merge

• User can merge two existing storage pools without moving data

• Consolidate storage pools with equivalent disks

• Merge storage pools with to create a mixed technology storage pool for Automatic Mode

• Rank Depopulation

• Storage Administrator can ask that a rank be removed from an storage pool

• Automatic, non-disruptive and transparent to host access, the used extents will be

reallocated to other ranks in the pool and rank freed

• Add to another storage pool using different extent size (large : small)

• Manual Volume Rebalance

• Redistributes a volume’s extents within a non-managed single-tier pool

• Same pool and can change EAM



Dynamic Volume Relocation

40

GUI: Migrate or DSCLI: manageckdvol –action migstart –eam rotateexts -extpool p10 1004

Before Volume Migration

Storage Pool 10


Storage Pool 0


1004

After Volume Migration

Storage Pool 0


Storage Pool 10


1004



Dynamic Storage Pool Merge process

41

GUI: Merge or DSCLI: chextpool –merge p10 p0

Before Storage Pool Merge

Storage Pool 10


Storage Pool 0


After Storage Pool Merge

Storage Pool 0

Rank 10 Rank 12 Rank 14Rank 0 Rank 2 Rank 4

Po

ol 1

0



Rank Depopulation

42

GUI: Unassign or DSCLI: chrank –unassign r2

Before Rank Depopulation

Storage Pool 0


After Rank Depopulation

Storage Pool 0

Rank 0 Rank 4

Unassigned

Rank 2



Manual Volume Rebalance

43

GUI: Redistribute or DSCLI: managefbvol -action migstart 1004

Before Manual Volume Rebalance

Storage Pool 0


1004


After Manual Volume Rebalance

Storage Pool 0


1004




Easy Tier – Manual Mode Summary

44

• Migrate Volume (Target Storage Pool, Extent Allocation Method)

• Can specify current storage pool or another storage pool

• Can specify extent allocation method (rotate volumes or rotate extents)

• Pause/Resume Volume Migration

• Pause puts volume in migration paused configuration state and stops initiation of any new extent migrations on a volume

• Resume puts volume in migrating configured state and continues migration

• Cancel Volume Migration

• Nullifies volume migration if it has not started and puts volume in normal configuration state

• Stops volume migration if it has started and puts volume in migration cancelledconfiguration state. Can request migrate volume to source or target storage pool to retry.

• Merge Storage Pool

• “Moves” all volumes in the source storage pool to the target storage pool

• Deletes source storage pool if merge is successful

• Rank Depopulation

• Can use Easy Tier to depopulate a rank and remove from an storage pool

• Automatic, non-disruptive and transparent to host access



Easy Tier Application – DS8870 and DS8880 Function

45

• Easy Tier Application will enable administrators

and applications to direct data placement based

on business knowledge and application

knowledge

• Database Systems and ISV solutions will be

able to provide performance tips to Easy Tier

• Will guide what, when, where and how

data is placed across the server and

storage systems dynamically

• Command entered by storage administrator

• Provide pin / unpin (assignment)

capability

• Tier placement

Easy Tier

Application

Data Placement



Easy Tier Application – Directive Data Placement

46

▪ Storage administrator can direct the data placement via GUI or DSCLI

– Building block for future software integration

• May be further adopted in the future by

– Operating systems

– Middleware applications for example database

• Provides a common API

▪ Command operates at the volume level

– Commands available for storage administrator to assign an entire volume to a specific tier (not just specific extents within the volume

▪ Easy Tier application data placement

– Passes on data placement requests

– Generates the migration plan

– Tier assignment options

– Specific tier (nearline, high performance flash, high capacity flash, enterprise)

– Exclude a tier (exclude nearline or exclude any HDD tier)

Storage Pool

Enterprise drives

Nearline drives

Flash drives

P4500

P2300P1200

Exclude

Nearline

Assign

HPF or

HCF

DefaultExclude

HDD



Easy Tier Application Support (assign a volume to a tier)

47



Easy Tier Application for IBM Z – DS8870 / DS8880 Function

48

Requires:

DS8870 LMC R7.4 or higher or DS8880

z/OS version 2.1 or higher

DB2 version 10 or 11 with SPE

▪ Initial use case: DB2 database reorganization under z/OS

– Without Easy Tier Application for IBM Z

• Database extents may currently be on high performance tier

• Database reorganization will move parts of the database to new

extents

– To Easy Tier, these extents may have been cold since they were

previously free space on the volume

– This may result in database extents now being relocated to lower

performance tiers

– With Easy Tier Application for IBM Z

• z/OS will query the DS8870/DS8880 to obtain average heat and tier

assignments

• During the database reorganization z/OS will specify the desired target

tier



Use Case – z/OS DB2 Database Reorganization

49

HDD

SSD

Storage

DB2

Re-org

DB2

Storage

SSD

HDD

Re-orgAssignment hint

Without Easy Tier Application for IBM Z

With Easy Tier Application for IBM Z

It takes time for ET to optimize the target datasets after re-org

Target datasets are already optimized before the re-org completes

FlashFlash



Implementation

50

▪ New interface between z/OS (Media Manager) and DS8000 Easy Tier API

▪ Introduces three new Media Manager functions and utilized by DB2

1) Report temperature of volume track ranges (query temperature)

• Returns token representing the average heat and tier allocation for the volume track

range(s)

2) Assign volume track ranges (hint)

• Specify the target tier explicitly

• Specify the temperature token

• Specify both the target tier and temperature token

3) Set temperature of volume track ranges (set temperature)

• Easy Tier will set the heat of the volume’s track range(s) to the average heat calculated

▪ Media Manager uses these commands to query and then set the desired

tier allocation

▪ Normal heat assignment takes over after the lease expires

– Assignment is not permanent and Easy Tier will manage the extents as normal



Heat Map Transfer Utility – DS8870 / DS8880 Function

51

Workload

Hotspot

Analysis

MM/GC/GM Replication

Integrated into GDPS, CSM and as a stand alone application under Windows



You Need Some Free Space for Easy Tier

52

• You must have free extents on ranks for Easy Tier to function

• Plan on having approximately 5-10 free extents per rank in the pool

• Allows Easy Tier to promote/demote and rebalance

• Example: 5 ranks in the pool would recommend 50 free extents in the pool

• Starting with DS8880 R8.1 default is to reserve extents

• Enabled by default

• chsi –etsrmode enable | disable

• More efficient use of free space as Easy Tier automatically calculates the amount of space it will require based on your specific environment

• Reserved space is reported as pool overhead in DSCLI/DSGUI



Easy Tier – Reporting From Within the User Interface

53

• DS8880 user interface now

has direct view of Easy Tier

activity

• Located within Performance

graphs within DSGUI

• Easy Tier data policy report

• Easy Tier data activity report

• Easy Tier Data movement report

• Select the storage pool then

select the type of Easy Tier

report desired

Select “Storage Pool”

from drop down then …



Easy Tier – Data Activity Report

54



Easy Tier – Data Movement Report

55



Easy Tier – Data Policy Report

56



Exporting Easy Tier Summary Files

57

• Can still offload the three CSV files

• Useful if you want the Skew Curve

• Disk Magic

• Understand the concentration of I/O against a

disk tier

• Useful if you want the details on extent

movement

• STAT utility program will not process R8.3+

Easy Tier metrics

• Excel spreadsheet provided to import and

format the CSV files if desired

• Requires Microsoft Excel at certain supported

levels

• Can also use your own methodology to

interpret the data

• Can export via GUI or DSCLI

command (shown in examples at right)



Migration Plan

58

• Easy Tier auto mode creates migration plans when enabled

• Plans are generated for both auto-rebalance and cross-tier migrations

• Auto-rebalance plans are generated every 6 hours

• Cross-tier migration (promote/demote) are generated at least once every 24 hours

• No extent migration will occur until the plan is generated

• Users cannot set the plan start/end times

• Easy Tier license must be installed before any ET functions will execute

• Easy Tier creates one migration queue per storage pool

• Each pool is optimized independently

• One storage pool is not compared to another storage pool

• Decision windows for easy tier are based on short term and long

term extent heat

• Short term heat has higher weight compared to long term extent heat

• Short term window is past 24 hours

• Long term window is past 7 days



Managing Easy Tier

59

-action etmigpause – Specifies that Easy Tier migrations of this storage pool are paused, including migrations that are required to relieve rank bandwidth performance issues. Easy Tier monitoring is unaffected by this action.

-action etmigresume – Specifies that Easy Tier migrations of this storage pool are resumed. Easy Tier monitoring is unaffected by this action.

-action etmonpause – Specifies that Easy Tier monitoring of this storage pool is paused. All current Easy Tier migration plans are unaffected, but no new migration plans are formed.

-action etmonresume – Specifies that Easy Tier monitoring of this storage pool is resumed. Any current Easy Tier migration plans are unaffected.

-action etmonreset – Specifies that all Easy Tier monitoring data (history), including migration plans, are erased. All new plans are based on new monitoring data.

-duration time – Specifies the duration of the pause time. For example, 4H would pause for 4 hours. Maximum duration is 168 hours (one week). Only valid for etmonpause and etmigpause.



Enabling Easy Tier

60

• License

• Order Easy Tier feature code #7083

• Download license key from DSFA and apply it to the

DS8000

https://www-03.ibm.com/storage/dsfa/ds8000/selectMachine.wss

• Enable Easy Tier

• Storage Image Properties (DS GUI)

• chsi –Etautomode all | tiered | none

storage_image_id

• Auto Mode

• all Automatically manage all single and multi-tier pools (default)

• tiered Automatically manage multi-tier pools only

• none Do not automatically manage any pools

• chsi –Etmonitor all | automode | none storage_image_id

• Monitor

• automode Only volumes managed by Easytier auto mode are monitored

• all All volumes in the system are monitored. (default)

• none No volume is monitored.

https://www-03.ibm.com/storage/dsfa/ds8000/selectMachine.wss



References

61

• IBM DS8000 Easy Tier Redpaper - REDP-4667

http://www.redbooks.ibm.com/abstracts/redp4667.html?Open

• IBM DS8000 Easy Tier Server Redpaper – REDP-5013

http://www.redbooks.ibm.com/redpieces/abstracts/redp5013.html?Open

• IBM DS8000 Easy Tier Application Redpaper – REDP-5014


• IBM DS8000 Easy Tier Heat Map Transfer Redpaper – REDP-5015


• IBM DS8870 Architecture and Implementation - SG24-8085

http://www.redbooks.ibm.com/abstracts/sg248085.html?Open

• IBM DS8880 Architecture and Implementation – SG24-8323


IBM DS8000 Easy Tier Volume Extent Allocation Chargeback Utility, REDP-4916











Questions

62

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