Overstock saves millions on database replication t

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oldenGate, from GoldenGate Software Inc., is a product few in the
storage space may have heard about. But in the right environment, the
software, which replicates structured data between databases, might be
a better choice than traditional backup software for storage
architects.
Jack M. Garzella, vice president of IT operations for discount online
retailer Overstock.com, estimated that the transition from EMC Corp.'s
Symmetrix Remote Data Facility (SRDF) migration software to GoldenGate
for the company's massive Oracle, SQL and DB2 databases will save him
millions on disk and maintenance costs in the years to come.
Overstock stores about 80 terabytes (TB) of data in its data center,
keeping the data in TeraData data warehouses, where they can apply
analytics to show, for example, a customer's propensity to buy certain
products in the future. Garzella said the company made the switch from
EMC storage and migration products to the TeraData warehouses and
GoldenGate software over the past year when its sales and marketing
departments demanded data be available to them instantaneously.
Garzella said that while the main benefit of GoldenGate's product
is its ability to do continuous, up-to-the-moment replication, the fact
that it is designed specifically for database data means he can use his
storage more efficiently.
"With SRDF to do replication, you're sending over blocks of data every
time they're changed," Garzella said. "With GoldenGate, we're not
backing up data we don't care about."
That data Garzella doesn't care about is called "non-committed" data
and refers to changes in a database not designated by the user to
remain "persistent" or permanent.
"SRDF and BCV [Business Continuance Volumes] were sending changed
blocks back and forth all the time. We're probably going to save about
4 TB of disk space with GoldenGate, which we can then designate for
other areas of our operation.
"In terms of pricing for the product, our licensing cost us hundreds of
thousands of dollars," he added. Over the next three to four years,
Overstock expects to save $5 million to $10 million by better utilizing
the disk it has and not having to buy any more.
This type of product, obviously, is not for everyone. Since
GoldenGate's replication process relies heavily on database log files,
it can't be used to back up, say, a Word document or e-mail.
According to Donna Scott, vice president and analyst with the Gartner
Group, customers with very large numbers of servers will use
traditional disk-based replication because there's less complexity in
the implementation. With GoldenGate, each application requires its own
instance of the software.
"But if you need higher availability, the ability to recover in a short
time frame, or most importantly, the ability to report on data from a
secondary database, this can work really well," Scott said.
Medical center migrates between databases
Businesses that have both large amounts of structured data and little
to no tolerance for downtime are ideal for GoldenGate. One such
business is the Montefiore Medical Center in New York City, the
flagship in a consortium of small hospitals attempting to implement a
"paperless" medical records system.
"Everything's automated now. There's no more paper," said Carl Baylis,
Montefiore's assistant director. "You can't tell a doctor that for the
next couple hours, no system will be available because you're doing
backup. It just can't happen."
Montefiore uses GoldenGate to migrate patient records between its
databases on a Hewlett-Packard Co. (HP) NonStop Tandem system, as well
as to replicate them to a duplicate NonStop box at its disaster
recovery site.
"GoldenGate is the only one that can take you down to the field level
with data," Baylis said. "Some other (database replication) products
will replicate records for you, but this has built in routines to
change data."
According to Noel Yuhanna, senior analyst with Forrester Research,
85% of data is currently unstructured, meaning GoldenGate has a niche
market at best at present. But products like it could grow in the next
few years, he said.
"Only 20% of enterprise data is ever changed," Yuhanna said. "This idea
that you don't really have to replicate all data in volumes of storage,
but you can only replicate a portion and ensure its consistency, is
catching on. There's a whole new evolution ready to take off to put
currently unstructured data into databases as well."
According to Sami Akbay, senior director of product marketing for
GoldenGate, while its product doesn't currently backup e-mail servers
or file systems at the moment, it could be coming.
"We think that in the future, an e-mail is going to be treated more
like a data transaction and potentially stored in a database," he said.
Other companies selling replication tools include: ITI Shadowbase,
Oracle Corp., Quest Software Inc., Sybase Inc. HP, Kashya Inc. and
XOsoft Inc. sell products more suited to unstructured files.


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