touted by Oracle as the “best platform for running the Oracle Database”. The
virtues of Exadata for dramatically improving database I/O performance are well
documented and overwhelmingly supported by customer references. But is Exadata also
the best platform for running Oracle Database In-Memory? After all, by
definition an in-memory database avoids I/O by holding data in DRAM. Doesn’t
that mean Exadata has no benefits for running an in-memory database compared to
similar x86 systems?
answer is “no”. Exadata is definitely the best platform for running Oracle
Database In-Memory, at least for any important database. If your in-memory
database is small enough to fit entirely in DRAM and you can tolerate periods
when the data isn’t available, and all you wish to do is read-only analytics
and occasional data loads, then Exadata may be overkill. It’s unlikely you
would be considering Exadata for such a situation anyway. Let’s discuss the 10
reasons to run Database In-Memory on Exadata:
On Exadata, you can configure an in-memory database to be fault-tolerant.
In-memory fault-tolerance is only available on Oracle Engineered Systems.
Your database can exceed the size of DRAM and scale to any size across memory,
flash and disk, with complete application transparency.
When your data doesn’t all fit in memory, you still get outstanding analytics performance
on Exadata from disk and flash. For the same reasons, populating the in-memory
data store from storage is very fast.
OLTP is fastest on Exadata and you can run in-memory analytics directly against
an OLTP database. Exadata enables Real-time analytics better than any other
Exadata is an ideal database consolidation platform and Oracle Database
In-Memory enhances that value even further. In many ways Oracle Database
In-Memory “completes” Exadata by applying in-memory performance techniques that
are similar to those used on disk and flash. The entire storage hierarchy
(DRAM, flash, disk) delivers maximum value. Adding Oracle Database In-Memory to
an existing Exadata system makes tremendous sense.
Exadata is highly optimized for RAC clustering, with special protocols over
InfiniBand for low-latency cluster interconnect. RAC clustering is how Database
In-Memory fault-tolerance is achieved and how large databases scale-out in
memory. No other platform supports RAC with in-memory like Exadata does.
On Exadata, the use of Oracle VM Trusted Partitions is allowed, reducing
software license costs. This is especially relevant for database options that
require less compute power than a full server.
Exadata elastic configurations, introduced in Exadata X5, enable custom configurations
that are perfectly tailored to specific workloads. If you need more memory but
not a lot of storage capacity you can create that configuration and only
purchase the Exadata servers needed for the job.
Exadata is the development platform for Oracle Database In-Memory. Issues are
discovered and fixed on Exadata first.
Exadata is also the primary platform for Oracle Database testing, HA best
practices validation, integration and support. The same reasons it is the best
platform for Oracle Database apply to Oracle Database In-Memory.