IBM informix: compared performance efficiency between physical server and Virtualized serverr

VM technology Vs Physical Servers: legends and facts

Eric Vercelletto

[email protected]

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http://www.iiug2014.org/speakers/viewpres.php?a=542






“Me” in a nutshell – Started my first Informix project in 1986, been an employee of Informix

Software in France and Portugal for 11 years, as tech support, trainer and Premium Accounts technical consultant

– I run Begooden IT Consulting , an IBM ISV company, exclusively focused on Informix technology services.

– I do what an Informix customer would expect from an Informix expert, but I do it with fun and passion. As of now in Europe and Northern Africa.

– I can also contribute to defend Informix positions in your company – Actions include the revival of the BeNeLux Informix User Group

(www.informix-clubhouse.org) , and technical leadership for the Informix division in the Infocura Group (Belgium)

– I run several blogs and websites: http://www.vercelletto.com http://levillageinformix.blogspot.com (in french)

– http://www.informix-swat.com : a community site (almost non-profit) where you can upload your resume for free if you are looking for an Informix job, assignments or technical missions, and search for a technician if you are an Informix end user company, IBM BP or HR

– I collaborate with Querix Ltd to evangelize and distribute those beautiful application tools in France and French speaking countries 2

http://www.informix-clubhouse.org/



http://www.vercelletto.com/

http://levillageinformix.blogspot.com/

http://www.informix-swat.com/



Agenda

What is virtualization

Who are the actors on the marketplace

Advantages of virtualization

Types of virtualization

Important questions to consider before boarding

Comparative benchmarks on x86 linux and PowerLinux

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Virtualization for beginners

• Virtualization is software or firmware

• virtualization is the process of simulating virtual instances of hardware resource within a physical server, into multiple watertight compartments – CPUs/cores,

– Memory,

– network components,

– operating systems,

– storage

• It is opposed to creating one physical instance of those resources in a physical server, which we have been calling “a server” for a number of years

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History of virtualization in 2 mn

• 1967: IBM Cambridge Scientific Center lab created the first hypervisor named CP-40. It runs on a modified S/360-40 mainframe computer, running CP/CMS Operating System.

• The key new feature is the support of dynamic address translation which finally allows multiple operation systems to run simultaneously in separate contexts named virtual machines.

• 1967-1972: extension of this concept so that all the kernel tasks can be virtualized, including interruptions and I/O

• This system is distributed to customers as a source code to be compiled, with no technical support….

• 1972: IBM launches VM/370 ported on System/370, with technical support

• 1985: IBM launches the PR/SM hypervisor for Logical Partitions(LPAR)

• 1999: Vmware launches Vmware workstation 1.0 on x86

• 2001: Vmware launches ESX Server 1.0

• 2005: Microsoft launches Virtual Server 2005

• 2008: Red Hat acquires Qumranet, including KVM in the package

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Who is on the marketplace ?

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Who owns the marketplace ?

Some names are on top: – Vmware ESX on x86 hosts,

hosting Windows and Linux – MS Hyper-V on x86 hosts,

hosting Windows only – IBM PowerVM on PowerXXX,

hosting Linux, AIX, i5 OS

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– Oracle VMServer on x86, hosting Windows, Linux, Solaris – Kvm on x86, PowerPC and PowerLinux hosting Linux – Xen on x86, ARM, hosting Linux, Solaris, MiniOS

Why should I virtualize my systems? (says the VM vendor)

– Many surveys show that physical servers use only 10 to 20% of the their system resources.

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77% waste

56% waste

85% waste

78% waste 54% waste

90% waste

Why should I virtualize my systems? (says the VM vendor)

– Many surveys show that physical servers use only 10 to 20% of the their system resources.

– Except for servers hosting “some” Red RDBMS

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No waste

Why should I virtualize my systems? • Consolidation of each system resource into

one global resource pool (hypervisor) => optimized resource usage

• no rack opening , just configure resource => faster, more versatile configuration and reaction capacity

• Native cloning functionality => simpler and faster deployment

• Good at High Availability => better service level to users community

• Many independent servers in one box => centralized, simplified administration

• More control on hardware expenses => Consequent IT budget savings

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VM types: type 1,native or bare-metal the physical server runs

under a special software layer called a hypervisor (Not a standard OS)

The hypervisor directly addresses and manages the hardware ressource in an highly optimized way

On top of this OS runs one or several Virtual Machines

Typical implementation of bare-metal VMs are IBM LPARs, Vmware ESXi, Oracle VM Server, IBM PowerVM …

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VM types : type 2 or hosted the physical server runs under a

« standard » OS like AIX, linux, Solaris, Windows

The hypervisor is one of the regular processes running in that OS

The hypervisor can run one or several Virtual Machines

Each Virtual Machine runs its own OS. OS’s can be different (Win,Linux …) Hosted OS must be hardware compatible

with host hardware (No AIX VM on a x86 box)

Typical implementation of hosted VM are VmWare Workstation, VmWare Player, VirtualBox, Citrix/Xen, MS Hyper-V

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Not type1 nor 2: IBM PowerVM

Before selecting a VM product: the right questions to ask

– I have this or that hardware: which VM product can run on this hardware ?

• Although many available hardware platforms can run a hypervisor, I must identify which ones can run on my hardware

• Some hardware platforms (x86 for instance), offer more hypervisors brands choice than others

• Some hardware platforms are very specific: IBM Power, Sun Sparc, etc.. And cannot run any hypervisor brand.

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– I want to run this or that OS, which hypervisor can host that OS?

• Many hypervisors brands can host Linux

• Fewer hypervisors brands can host Windows

• Few hypervisors brands can host specific platforms like IBM Power or Sun Sparc

• Very few hypervisors brands can host different OS flavors

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– Not all VM types are efficient to any application • Bare metal VMs are more adapted to intensive

production applications because they work very close to the hardware level, but they require a fully dedicated hardware.

• Hosted VMs offer more flexibility than bare metal in the sense that they do not need a dedicated hardware, but they are also less powerful

– Do I need flexibility, do I need performance or both ?

– Must I/Should I/Can I virtualize application servers ? – Must I/Should I/Can I virtualize database servers ?

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Virtualization and Application Servers

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• In most cases, application servers do not have specific requirements in terms of hardware or OS configuration

• In most cases, they are not very sensitive nor demanding in terms of performance

• In most cases, the applications do not provide any system to ensure high-availability

• => In most cases, application servers are good candidates for virtualization for the above listed reasons

Virtualization and Database Servers • In most cases, database servers have specific

requirements in terms of hardware and OS configuration

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• In most cases, they are very sensitive and demanding in terms of performance



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• In all cases, we love and cherish our database servers because we are responsible for them



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• In all cases, we love and cherish our database servers because we are responsible for them

• Because of these reasons, we are somewhat reluctant to believe in the VM software sales person speech

Virtualization and DB Servers What cannot we forget about?

• Database servers generally do no like running on poor IO sub-

systems • Database servers generally do not like sharing CPU power with

other unpredictable applications • Database servers work most of the time in SHMEM, the memory

subsystem cannot suffer from consolidation side effects • Database servers are generally greedy in terms of Network

performance • These points are critical factors to consider before choosing a VM

technology and configuring it. • Hypervisor configuration and administration can get more complex

than the vendor said • The sold configuration may be undersized and performance issues

sub-estimated, even if virtualization is sold as a versatile miracle. • Those basic requirements must NOT be sacrified on the altar of

the Virtualization

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What is the IBM Informix Hypervisor Edition ?

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Hypervisor Edition is packaged to be installed on private cloud appliance

It has the full set of Ultimate or Enterprise editions functionality, with no limitations No limitation on scalability No limitation on MACH11 nodes

It runs on IBM PureSystems Flavors are AIX and RedHat Linux Licensing works on a PVU metrics model

How does Informix failover ?

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Informix HDR replication mainly consists in replaying the logical logs on the other side

HDR logs buffer contents is transported to the replicate on a private tcpip connection

HDR knows about SQL transaction state HDR can be integrated in a MACH11 cluster

How do VM’s failover ?

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At failure time, a clone image of the Primary server is started on the other server This feature works quite well Storage has to be constantly and thouroughly replicated, unless you want unique

storage Storage replication is generally an expense technology Storage replication is a high bandwidth consumer Storage replication is blind about sql transactions

VM failover Vs Informix failover ?

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VM complete failover requires costly storage replication VM Failover is totally blind about db activity If you use VM failover, you won’t probably use MAC11 cluster Informix replication replication is much more flexible in the sense that

replication levels can be mixed: HDR, ER RSS SDS

Now

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Define the benchmark

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Objective: obtain elements and figures that can help me to make a ponderate and accurate decision about the choice of a Virtual technology Evaluate VMWare vmplayer on a cheap linux X86_64 No Vmware ESX available on time for evaluation Evaluate IBM PowerVM on P750 PowerLinux

(thanks to IBM Montpellier Client Center Benchmark Team)

Methodology: compare the efficiency of a physical (or nearly physical) server with the same box used as a Virtual Machine Compare raw hardware performance (CPU power, Storage, Memory…) between

physical and VM. We will use the unixbench opensource benchmark for this

Fire a series of TPCC Benchmark runs to obtain the best possible tpmC and define the inflexion point for physical and VM. We will use our tpc-c for Informix benchmark for this., local esql/c

application talking on ipcshm

The x86 Box

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unixbench on x86Linux CentOS 6.5 Physical Server

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Test result

Dhrystone 2 using register variables 15 643 048

Double-Precision Whetstone 16 642

Execl Throughput 28 556

File Copy 1024 bufsize 2000 maxblocks 1 335 430

File Copy 256 bufsize 500 maxblocks 344 462


Pipe Throughput 8 582 254

Pipe-based Context Switching 1 815 010

Process Creation 77 203

Shell Scripts (1 concurrent) 30 950


System Call Overhead 9 506 088

Overall unixbench 41 789 106

Unixbench on x86Linux CentOS 6.5 VMWare Server

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Test result

Dhrystone 2 using register variables 15 345 585

Double-Precision Whetstone 16 309

Execl Throughput 18 905


File Copy 256 bufsize 500 maxblocks 294 858


Pipe Throughput 7 564 153

Pipe-based Context Switching 1 679 017

Process Creation 52 233



System Call Overhead 9 148 986

Overall unixbench 38 125 613

Unixbench on Intel Linux CentOS 6.5 comparison

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VM05

SUPERGIGA

Deeper insight on IO comparison

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Unixbench on x86Linux CentOS x86 comparison

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Overall unixbench comparison

VM05

SUPERGIGA

TPC-C on the CentOS x86 physical server

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2014-04-23_122345_010w_10t 35463,656 tpmC

Transaction Count MinRT AvgRT MaxRT 90% 90thAvg <2s <5s <10s <20s <40s <80s <150s >150s

Delivery 2021 0,012 0,357 3,082 100 0,357 2012 9 0 0 0 0 0 0

Payment 37104 0 0,05 1,411 100 0,05 37104 0 0 0 0 0 0 0

New Order 35388 0,001 0,059 1,139 100 0,059 35388 0 0 0 0 0 0 0

Stock Level 3811 0,001 0,013 0,511 100 0,013 3811 0 0 0 0 0 0 0

Order Status 3823 0 0,033 1,122 100 0,033 3823 0 0 0 0 0 0 0

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2014-04-23_144824_020w_10t 41703,255 tpmC


Delivery 3766 0,007 0,248 3,844 100 0,248 3716 50 0 0 0 0 0 0

Payment 43759 0 0,088 1,889 100 0,088 43759 0 0 0 0 0 0 0

New Order 41444 0,001 0,11 1,8 100 0,11 41444 0 0 0 0 0 0 0

Stock Level 4673 0,001 0,021 0,914 100 0,021 4673 0 0 0 0 0 0 0

Order Status 4727 0 0,047 1,635 100 0,047 4727 0 0 0 0 0 0 0

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2014-04-23_162246_030w_10t 33846,437 tpmC


Delivery 2071 0,009 0,744 5,899 99,95 0,741 1924 146 1 0 0 0 0 0

Payment 35188 0 0,136 3,152 100 0,136 35174 14 0 0 0 0 0 0

New Order 33671 0,001 0,213 2,011 100 0,213 33670 1 0 0 0 0 0 0

Stock Level 3864 0,001 0,057 0,932 100 0,057 3864 0 0 0 0 0 0 0

Order Status 3973 0 0,036 1,791 100 0,036 3973 0 0 0 0 0 0 0

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/2014-04-23_162518_040w_10t 26069,394 tpmC


Delivery 1447 0,009 1,028 18,528 94,54 0,649 1191 177 68 11 0 0 0 0

Payment 26859 0 0,18 6,367 99,97 0,179 26636 216 7 0 0 0 0 0

New Order 26009 0,001 0,172 9,255 99,93 0,168 25861 131 17 0 0 0 0 0

Stock Level 3283 0,001 0,753 52,971 98,2 0,057 3219 0 0 5 34 25 0 0

Order Status 3370 0 0,041 5,729 99,97 0,039 3357 12 1 0 0 0 0 0

TPC-C on a hosted Linux x_86Vmware

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2014-04-24_064122_010w_10t 26689,595 tpmC


Delivery 2438 0,013 0,231 1,175 100 0,231 2438 0 0 0 0 0 0 0

Payment 26908 0 0,067 0,899 100 0,067 26908 0 0 0 0 0 0 0

New Order 26677 0,003 0,113 1,359 100 0,113 26677 0 0 0 0 0 0 0

Stock Level 2737 0,001 0,046 0,548 100 0,046 2737 0 0 0 0 0 0 0

Order Status 2791 0 0,025 0,759 100 0,025 2791 0 0 0 0 0 0 0

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2014-04-24_070332_020w_10t 26270,711 tpmC


Delivery 2578 0,011 0,151 2,45 100 0,151 2577 1 0 0 0 0 0 0

Payment 23417 0,001 0,191 2,312 100 0,191 23416 1 0 0 0 0 0 0

New Order 24711 0,005 0,198 2,879 100 0,198 24688 23 0 0 0 0 0 0

Stock Level 2660 0,001 0,035 0,952 100 0,035 2660 0 0 0 0 0 0 0

Order Status 2717 0 0,025 1,713 100 0,025 2717 0 0 0 0 0 0 0

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2014-04-22_124448_040w_10t 17288,719 tpmC


Delivery 1933 0,011 0,578 4,178 100 0,578 1835 98 0 0 0 0 0 0

Payment 14515 0,001 0,429 2,741 100 0,429 14475 40 0 0 0 0 0 0

New Order 16678 0,003 0,543 3,834 100 0,543 16326 352 0 0 0 0 0 0

Stock Level 2045 0,001 0,093 1,058 100 0,093 2045 0 0 0 0 0 0 0

Order Status 2178 0 0,004 0,224 100 0,004 2178 0 0 0 0 0 0 0

TPC-C on the Linux x86 physical server tpcc for 100 users vmstat-wise

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TPC-C on the CentOS x86 VM tpcc for 100 users vmstat-wise

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TPC-C on the Linux x86 comparison in tpmC

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supergiga

vm05

Linux x86 Vmware ESX reported missing

• We were supposed to have a Wmware ESX Server

• We did not have this server on time

• We are somewhat frustrated, but we’ll definately run this benchmark on VMWare ESX

• Since Vmware ESX is bare-metal, we want to believe that results will be much better than vmplayer

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Net External

Client

HMC 10.3.70.100

Admin Network 10.7.22/24

VIOS2 1 CPU Dedicated

4 GB of memory

VIOS1 1 CPU Dedicated

4 GB of memory

Zone 1 Zone 2

Po

rt 1

FC adpt

Po

rt 2

Po

rt 1

FC adpt

Po

rt 2

Disks multipath

Node 3

SVC IOgroup 0

SVC IOgroup 1

D-BGOOD-IFX 16 CPU Dedicated -- 128 GB of memory

Node 4

Node 2 Node 1

Virtual Eth

10.7.22.10

Mutualized 8 ranks of

8 disks 10krpm

Disks Zone

Power 750 8408-E8D YOb02R

32 P7+, 1 TB RAM

IBM DS8000

Virtual FC (npiv)

Virtual FC (npiv)

Mutualized SATA disks

(OpenVPN)

The IBM PowerLinux partition Kindly provided by IBM Montpellier Client Center

Unixbench on IBM PowerLinux dedicated CPU+dedicated Vs Virt CPU+Virt IO

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Unixbench on IBM Power RedHat 6.5 comparison

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OverallUnixbench

OverallUnixbench

TPC-C on IBM PowerLinux Dedicated CPU + Dedicated IO

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050w_10t 96503 tmpC


Delivery 10744 0,023 0,126 1,14 100 0,126 10744 0 0 0 0 0 0 0

Payment 103685 0,001 0,094 0,994 100 0,094 103685 0 0 0 0 0 0 0

New Order 96503 0,006 0,147 1,314 100 0,147 96503 0 0 0 0 0 0 0

Stock Level 10914 0,003 0,044 0,854 100 0,044 10914 0 0 0 0 0 0 0

Order Status 11299 0 0,011 0,314 100 0,011 11299 0 0 0 0 0 0 0

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060w_10t 92922 tpmC


Delivery 9821 0,026 0,122 1,147 100 0,122 9821 0 0 0 0 0 0 0

Payment 87285 0 0,166 1,292 100 0,166 87285 0 0 0 0 0 0 0

New Order 92922 0,003 0,148 1,436 100 0,148 92922 0 0 0 0 0 0 0

Stock Level 10072 0,002 0,015 0,315 100 0,015 10072 0 0 0 0 0 0 0

Order Status 10171 0 0,002 0,095 100 0,002 10171 0 0 0 0 0 0 0

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080w_10t 90331 tmpC


Delivery 10155 0,054 0,301 1,259 100 0,301 10155 0 0 0 0 0 0 0

Payment 96109 0,002 0,158 0,907 100 0,158 96109 0 0 0 0 0 0 0

New Order 90331 0,014 0,257 0,969 100 0,257 90331 0 0 0 0 0 0 0

Stock Level 10588 0,004 0,06 0,567 100 0,06 10588 0 0 0 0 0 0 0

Order Status 10982 0,001 0,027 0,291 100 0,027 10982 0 0 0 0 0 0 0

PowerVM Dedicated CPU + Virtual IO

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050w_10t 101 952 tpmC


Delivery 11009 0.013 0.052 0.606 100.00 0.052 11009 0 0 0 0 0 0 0

Payment 100293 0.000 0.131 0.895 100.00 0.131 100293 0 0 0 0 0 0 0

New Order 101952 0.003 0.132 0.931 100.00 0.132 101952 0 0 0 0 0 0 0

Stock Level 10938 0.003 0.025 0.549 100.00 0.025 10938 0 0 0 0 0 0 0

Order Status 11136 0.000 0.004 0.196 100.00 0.004 11136 0 0 0 0 0 0 0

080w_10t 94 436 tpmC


Delivery 11253 0.016 0.047 0.532 100.00 0.047 11253 0 0 0 0 0 0 0

Payment 97676 0.000 0.130 1.314 100.00 0.130 97676 0 0 0 0 0 0 0

New Order 94436 0.003 0.281 4.618 100.00 0.281 94376 60 0 0 0 0 0 0

Stock Level 10407 0.003 0.098 0.946 100.00 0.098 10407 0 0 0 0 0 0 0

Order Status 11272 0.000 0.004 0.158 100.00 0.004 11272 0 0 0 0 0 0 0

TPC-C on IBM PowerLinux VIRT CPU + VIRT IO

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050w_10t 90808 tpmC


Delivery 10063 0,017 0,044 0,29 100 0,044 10063 0 0 0 0 0 0 0

Payment 90507 0 0,139 0,836 100 0,139 90507 0 0 0 0 0 0 0

New Order 90808 0,004 0,151 1,001 100 0,151 90808 0 0 0 0 0 0 0

Stock Level 9907 0,002 0,031 0,561 100 0,031 9907 0 0 0 0 0 0 0

Order Status 10134 0 0,003 0,233 100 0,003 10134 0 0 0 0 0 0 0

060w_10t 87195 tpmC


Delivery 10063 0,018 0,044 0,288 100 0,044 10063 0 0 0 0 0 0 0

Payment 89467 0 0,126 1,115 100 0,126 89467 0 0 0 0 0 0 0

New Order 87195 0,004 0,218 1,529 100 0,218 87195 0 0 0 0 0 0 0

Stock Level 9611 0,003 0,067 0,828 100 0,067 9611 0 0 0 0 0 0 0

Order Status 10105 0 0,002 0,244 100 0,002 10105 0 0 0 0 0 0 0

080w_10t 83148 tpmC


Delivery 10003 0.013 0.050 0.313 100.00 0.050 10003 0 0 0 0 0 0 0

Payment 84886 0.000 0.155 1.136 100.00 0.155 84886 0 0 0 0 0 0 0

New Order 83148 0.004 0.310 2.106 100.00 0.310 83147 1 0 0 0 0 0 0

Stock Level 9333 0.003 0.098 0.990 100.00 0.098 9333 0 0 0 0 0 0 0

Order Status 10047 0.000 0.003 0.155 100.00 0.003 10047 0 0 0 0 0 0 0

TPC-C on the TPC-C on IBM PowerLinux dedCPU+dedIO

tpcc for 800 users vmstat-wise

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TPC-C on the TPC-C on IBM PowerLinux Virt CPU +Virt/IO


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TPC-C on the TPC-C on IBM PowerLinux Ded/CPU +Virt/IO


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TPC-C on IBM PowerLinux comparison

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D-BGOOD-DCPU,DIO

D-BGOOD-VCPU,VIO

D-BEGOOD-DCPU,VIO

Conclusions

• Vmplayer – It is simple to use and very handy to quickly build

environments with few ressources

– Not tailored for performance

– Use for dev or unit or integrartion test environments

• powerVM – Very close to the hardware level

– Very good performance

– A real solution for production environments

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Special thanks

• Art Kagel (@himself)

• Vladimir Kholobrodov (IBM,Kansas City) • Fabrice Moyen & Sébastien Chabrolles(IBM, Montpellier)

• Laurent Revel (IBM, Montpellier)

• Gonçalo Ruivo (www.sumatra-surftrip.pt)

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VM technology Vs Physical Servers: legends and facts

Questions?

Eric Vercelletto

[email protected]

53




