Enterprises that trusted in the mainframe myths and moved their
corporate databases to distributed platforms are spending 100 percent
more than necessary on database servers, creating data integrity issues
and increasing the data risk exposure by constraining the ever-shrinking
backup window. By moving databases from shared-nothing distributed data
servers to the shared storage environment of IBM zEnterprise systems
and putting the applications on Integrated Facility for Linux (IFL)
processors and an IBM zEnterprise BladeCenter Extension (zBX), IT
executives can reduce their ecosystem costs by more than 50 percent per
year. At Robert Frances Group (RFG), we completed a Total Cost of Ownership
(TCO) analysis of the traditional distributed Linux and Microsoft
Windows environment vs. a zEnterprise with zBX environment that
consolidates the databases on the mainframe and found the distributed
environment to be twice as expensive. Our study used the standard
three-year zEnterprise leasing and refresh strategy and traditional
five-year purchase plan for the distributed x86 scale-out scenario. IT
executives should evaluate the shared zEnterprise database server
alternative to lower costs, improve productivity and reduce data risk.
Additionally, IT executives should work with IBM or a third-party lessor
to structure a package that best meets current and future business,
financial and IT objectives. We had several ideas and hypotheses in mind before conducting our analysis. Specifically:
• The scale-out distributed server model using shared-nothing databases
is costly and inefficient, creates data integrity and operational
exposures, and fails as a best practice. A switch to using the mainframe
as a database server eliminates the need for database duplication and
synchronization since the mainframe uses a shared-everything
architecture. While the acquisition cost of the zEnterprise and zBX
servers collectively runs more than distributed x86-based servers, this
is more than compensated for by the drastic reduction in database arrays
and their associated costs. IT executives should assess the platform
options holistically rather than piecemeal to identify the optimal
solution.
• A zEnterprise environment can place Linux applications on IFLs and
Windows applications on a zBX. Using this tightly knit,
workload-optimized solution reduces the number of processors required,
improves application and system management, and uses a high-speed
interconnect so performance isn’t diminished when shifting to a
shared-everything database engine. A zEnterprise solution enables
enterprises to improve automation, control, security and visibility to
their applications and databases without degrading performance. IT
executives should determine which applications and databases should move
to a zEnterprise environment and perform a TCO analysis to gain
executive buy-in for the shift.
• Several non-financial gains accrue when moving to a shared-everything
storage environment and these should also be factored into the
decision-making process. Having a single copy of data means there’s only
one version of the truth, all outputs and reports will be consistent
and keeping things in synch won’t require manual manipulation, which is
error-prone. Most enterprises today spend between 25 and 45 percent of
their time synchronizing the many database copies. The associated time
consumption used for duplication also creates a backup exposure; some
backups don’t occur when administrators are pressed for time. Business
and IT executives should consider these data integrity and risk
exposures.
• Most IT executives have blindly accepted as fact the theorem that
distributed processing is the least expensive solution. This hypothesis
has gained ground because of a focus on a Total Cost of Acquisition
(TCA) perspective. If the only valid cost analysis is the TCA of
servers, then this might hold water. However, when the entire ecosystem
is analyzed—including administrator costs, application and middleware
software license and maintenance fees, cabling, networking, servers,
storage, floor space and power and cooling—this theory falls apart.
• When the zEnterprise is used as a database server and IFLs and zBX
are fully leveraged—and the analysis occurs holistically—a different
picture emerges. The zEnterprise environment costs more than 50 percent
less than that of a distributed x86 ecosystem, mostly due to the savings
on storage, administrator, warranty and software costs.
• The mainframe architecture supports shared-everything storage while
all distributed operating system platforms use a shared-nothing
architecture. The mainframe architecture is unique in that multiple
workloads share processors, cache, memory, I/O and storage. Moreover,
zEnterprise systems provide data, IT and storage management practices
and processes that facilitate and simplify the centralized, shared
environment and enable application and database multitenancy. This means
mainframe applications can share a single instance of a database, such
as customer data, while distributed systems force the creation of a copy
for each application’s use.
• Often, companies have between seven and 50 copies of the same
database in use, so every terabyte of data stored is expanded by
requirements for archiving, backup, mirroring, snapshots, test systems
and more (see Figure 1). This data store expansion is then duplicated by
the number of copies the distributed systems require. Thus, 1 TB of
data in a distributed environment could grow to in excess of 100
TBs—more than 10 times the amount needed when databases are shared using
a zEnterprise. There are software clustering solutions to get around
this distributed duplication phenomenon and some of the storage sprawls,
but they’re partial fixes and only address certain data sets.
• Mainframe storage capacity requirements are a fraction of what’s
required for distributed systems. Annual acquisition costs for
additional storage on a mainframe will be far less than that for
distributed storage solutions. The capital expenditure (CAPEX) savings
from the differential in storage costs when mainframes are used as a
database engine far exceed the added expense of the mainframe hardware.
The mainframe’s smaller storage footprint will reduce the operational
expenditures (OPEX) and lower the TCO.
The Methodology
We hypothesized that a large Small to Midsized Business (SMB) with
revenues between $750 million and $1 billion might operate a more
economical data center environment if it used the new zEnterprise
architecture and the mainframe as a database server. Most SMBs run their
applications on Windows and/or Linux on x86-architected servers that
don’t offer the advantages of a scale-up architecture. Let’s assume AB
Co. (ABCo) runs 500 applications with 75 percent of them (375) executing
on top of the Windows operating system. The remaining applications
(125) run on Red Hat's Enterprise Linux. Additionally, 10 percent are
CPU-intensive and require their own blade servers. All other
applications operate under either VMware or KVM, depending on whether
they’re Windows or Linux applications, respectively. The application
workload growth rate is at 20 percent per year.
We also assumed a Storwize V7000 Unified Storage System houses the
databases for the mainframe and distributed environments. To keep the
analysis from becoming too complex, only two sizes of databases are used
(1 and 2 TBs) and each application accesses 10 databases, half of each
size. The storage growth rate is 25 percent. There are a total of 70
unique databases, half of each size. For the purposes of the study, only
the production servers and storage are included; excluded are the
archive, backup and snapshot copies of data. Because a Storwize storage
solution is used, we assume a 60 percent utilization is achieved in all
environments.
We further assumed that 126 TB of storage is required to handle storage
needs for the first 12 months of operation. This includes an additional
20 percent for duplicate databases for the mission-critical
applications. On the x86 side, since this is a shared-nothing framework,
a minimum set of seven copies of databases would be needed. This
results in the total initial storage capacity of 770 TB being required
to support the storage needs of the first year’s operation. Finally,
note that DB2 10 for z/OS is the database software used to access all
databases.
The x86 server scenario uses all IBM 16-core HX5 blade servers for
application and database processing. The zEnterprise uses the Central
Processing (CP) environment to handle all the database interactions,
exploits IFLs for all of the Linux workloads and the zBX for the Windows
workloads. In this way, each workload is allocated to the server
platform best-suited to perform the task. We further assumed the x86
servers were purchased and kept in operation throughout the five-year
analysis period while the zEnterprise boxes were leased and refreshed at
the end of three years.
The Distributed Approach
We assumed the distributed environment used 24 16-core HX5 blade
servers to handle the 500 Linux and Windows applications. Since these
environments require shared-nothing storage, the Storwize solution ends
up requiring 126 enclosures and 1,285 raw TB of storage. All the
hardware was purchased with the financing of the purchase price spread
out over the five-year period. To meet the additional capacity demands
year-over-year, new servers or storage arrays were purchased using the
same methodology.
The Mainframe Solution
We configured a zEnterprise z196 model 501 to handle the database
management, along with 13 IFLs and a zBX containing 14 16-core HX5 blade
servers. The only application in the CP is the DB2 database management
package. None of the distributed applications are rewritten to run on
the CP. The Linux applications are relocated to IFLs, where there’s
better memory management, allowing for greater utilization (up to 60
percent) and performance. We assume that 10 Linux applications can run
on each IFL. Due to the improved management capabilities of a zBX, we
assume a 10 to 15 percent performance improvement per HX5 on the zBX
compared to a standard distributed environment.
In the zEnterprise environment, the data I/O requests start from the
applications in the IFLs and zBX blades and are relayed to the DB2
application in the CP for handling. Only the DB2 application in the CP
interfaces with the Storwize storage arrays. This environment initially
requires 21 shared-storage Storwize enclosures and 214 raw TBs of
storage.
At the end of the three-year lease, the zEnterprise model 501 is
upgraded to a model 601 so it could handle the database workload through
the next three-year period. As is common when upgrading a mainframe,
IFLs are also upgraded. The cost to upgrade each IFL is $6,000 and is
factored into the new lease. When the HX5 blade servers are upgraded at
the end of the third year, the number of servers shrinks by two. We
assumed that even though there are two fewer servers in use in year
four, the licenses and associated software maintenance should be
continued. This way, when it’s necessary to add more servers in the last
year of the analysis, only the software for two servers needs to be
factored in instead of four.
Using the previous scenario, we find that, as expected, the cost of the
mainframe environment exceeds that of the distributed x86 servers by
$9.4 million to $5.3 million on a Net Present Value (NPV) basis.
However, the $4.1 million differential is more than recouped on the
storage side. The zEnterprise storage costs come in at $3.8 million on
an NPV basis while the distributed storage costs exceed $21.7 million.
This is a net savings in excess of $13.8 million. Moreover, this savings
is more than the cost of the entire zEnterprise ecosystem.
Analysis Considerations
The TCO analysis was done over a five-year period. On the leasing side,
the original zEnterprise processors (CP, IFLs and HX5 blades) are
returned after 36 months and replaced by the latest-generation servers.
By swapping out the old hardware and moving to more powerful processors,
the CP growth is contained and excess capacity is minimized. The IFLs
growth is retarded and maxed out at 25 while the HX5 blades shrink
initially upon replacement and then expand to a total of 22 blade
servers. The Storwize arrays grow from the initial 128 TBs (214 raw TBs)
to 314 TBs (523 raw TBs). However, the number of enclosures only grows
from 21 to 28. This small expansion is the result of leasing the storage
and replacing the units with more dense storage at the end of the
three-year lease period.
The purchase model assumes that all servers are kept in service for a
full five-year cycle and that, whenever added capacity is required,
additional servers are bought. Thus, with the purchase model, the 24
servers slowly expand at a 20 percent rate annually until it reaches 48
servers by the end of the five-year cycle. The Storwize arrays expand
from an initial 771 TBs (1,285 raw TBs) to 1.9 PBs (3.14 raw PBs) over
the five-year period. The number of enclosures jumps from 126 to 216 in
the same period, as none of the arrays or enclosures are swapped out.
On the software side in the purchase model, we assumed that payments
for all software licenses were financed over the five-year period.
However, in the leasing model, the costs of software licenses were
spread out over the term of the lease. The leasing model selected was a
Fair Market Value (FMV) lease obtained from IGF at a reasonable, but not
most favorable, lease rate. The cost of capital and the purchase
financing rate were estimated to be 6 percent.
Findings
We found it’s more than 100 percent more costly to distribute database
serving among the distributed x86 servers than to consolidate the
databases onto a common shared database platform using the zEnterprise
as a database server. This cost savings is true on a current dollar
basis and NPV basis.
The primary inhibitor to selection of the zEnterprise database engine
approach is the fact the zEnterprise server alternative is more than
twice as expensive as the x86 servers. Business and IT executives see
the price tag differential—$1.14 million for the x86-based servers vs.
$3.88 million for the zEnterprise servers over the five-year period—and
conclude mainframes aren’t the way to go. However, the server costs pale
when the database environment is factored into the equation. The cost
for the distributed shared-nothing x86 storage systems comes in at $10.7
million while the mainframe storage system only costs $2 million over
the five-year period. The $8.7 million savings in storage acquisition
costs more than compensates for the $2.74 million in added zEnterprise
acquisition expenses.
When all the TCO factors are examined, the purchased x86 solution runs
almost $34.8 million, or on an NPV basis, just over $27 million. The
leased zEnterprise solution comes in at more than 50 percent less—$16.5
million on a current dollar basis, or $13.2 million on an NPV basis.
The zEnterprise solution costs remained fairly flat over the five-year
period, with most of the yearly expenses in the low $3 million range.
There were two years when that didn’t occur—years three and four, where
the expenses jumped to $4 million and then dropped to $2.7 million. The
purchased x86 solution saw its total annual costs climb from $4.8
million in year one to $9.4 million at the end of the five years (see
Figure 2).
Details
The out-of-pocket charges to install the zEnterprise alternative is a
wash compared to the installation costs of the x86 solution. However,
there’s an $18.2 million savings that’s achieved by using the mainframe
as a database server. Approximately one-third of that is hardware costs
while another 27 percent savings comes from administrator costs.
In the purchased option, there was a requirement for additional
software licenses and maintenance fees and growth in energy consumption.
The total additional software expenditures in the purchase model
exceeded $3.4 million, with most of that being software license and
warranty fees. Similarly, power and cooling charges increased by more
than $811,000 over the five years in the purchased model, or about 4
percent of the added expenditures (see Figures 3 and 4).
Other Considerations
There are several other advantages the zEnterprise platform offers that
weren’t included in the cost analysis. Some of these are server-related
while others are tied to the compressed storage footprint. Having just
one copy of data reduces the risk of data integrity exposures caused by
application or timing errors. This eliminates the need for syncing
copies, which can consume between 25 and 45 percent of administrator
time. Most companies today are concerned about the shrinking backup
window; eliminating synchronization frees up time for backups. Companies
often are hard pressed to get all their backups done as scheduled and
are exposed, should a backup run fail to complete. There’s little time
for a rerun. If a recovery is necessary, the most recent recovery point
may not have been captured, potentially causing data integrity problems,
lost revenues and customer dissatisfaction.
zEnterprise processors are architected for maximizing throughput and
system utilization when consolidating multiple workloads on a server
complex. Mainframes can consistently handle utilization levels of 80 to
100 percent without freezing or failing. Moreover, mainframes are
recognized as the best platform for continuous and high availability,
investment protection, performance, reliability, scalability and
security. Because of its unique scale-up architecture, the cost per unit
of work on a mainframe goes down as the workload increases; that isn’t
the case with the scale-out architecture (see Figure 5). The
cost/performance gains are due to the need for fewer administrators per
unit of workload and higher levels of utilization. Mainframes can
achieve higher utilization levels because of memory and processor
sharing. Under the covers, there are hundreds of I/O processors to
handle the data movements, freeing the central and specialty processors
to focus on the application and task workloads.
This analysis didn’t examine the added costs of development systems.
Here, too, the zEnterprise environment can share databases while each of
the x86 test systems would have its own copies of the data. Moreover,
users archive and back up the various databases and create snapshots. As
shown in Figure 1, these database duplicates increase the rate of
storage growth in the distributed environment over that of the mainframe
solution. If these additional costs were added to the TCO, the
zEnterprise advantage would improve even more.
Conclusion
We found that the zEnterprise reduced costs in all the TCO factors
considered. zEnterprise hardware costs were 33 percent less than the x86
ecosystem costs while administrator costs were 28 percent lower.
Warranty costs were 16 percent less and the cost of software dropped by
12 percent when the mainframe alternative was used. For much smaller
SMBs or departmental systems, mainframes aren’t the answer, but for
midsize to large enterprises, the economies of scale provided by
mainframe solutions make a compelling case for organizations to
re-examine their assumptions and consider the zEnterprise as a target
environment.
Mainframe myths have led to higher data center costs and
suboptimization. Organizations running hundreds of applications and
multiterabytes of data should re-evaluate their architectural platform
choices and evaluate whether or not a zEnterprise solution might provide
them with a lower TCO. IT executives should insist on an evaluation
that addresses the financial facts and ignores the religious platform
wars. In today’s environment, IT must select and implement the best
target platforms. The zEnterprise as a database server is a great
choice.
