Exadata V2: Affordable Database Scalability
The newest database system from Oracle and Sun Microsystems is a beauty. It easily scales from one quarter rack to eight full racks of nodes with just cabling (and nodes of course). If that's not enough for you, it can be expanded even further with larger switches, which are available from Sun. As for the upper-end configuration, an Oracle overview of Exadata storage stated that there is, "No practical limit to number of Cells that can be in the grid," referring to the storage nodes (explained below). If a quarter rack is too much for you, the architecture allows the system to be run with a single pairing of one database node and one storage node, but you will need to add in switching when if you decided to expand.
Oracle and Sun are currently only offering this server with X4170 Database nodes and X4275 Storage nodes running Oracle Enterprise Linux. There does not, however, seem to be anything limiting the use of other x86 systems and there are plenty in the Sun arsenal. I also suspect that a Solaris x86 and Solaris SPARC versions are in the works if not already done. These will allow Oracle to take advantage of more of Sun technologies such as CMT and ZFS.
The Exadata storage nodes are not just used as RAID arrays but actually as subsystems that do some of the database work. They actively run queries on their portion of the compressed data, and return only relevant data to the database nodes. This helps eliminate unnecessary interconnect traffic. The interconnect is often a bottleneck of multi-node systems such as this, so any way of cutting down on traffic is most welcome. They are also using QDR InfiniBand and four PCIe cards with flash cache to accelerate workloads. Oracle has optimized it's database to use this flash, increasing its performance so much that they now allow OLTP and even mixed workloads.
OLTP in this type of system is quite distributive. It has traditionally been handled by vertically scaled systems, which add more processors in a single node versus adding more nodes to handle a larger workload. There are various technical details which made this necessary and congratulations to Oracle for overcoming them. What's the big deal here? Money. Smaller nodes typically cost less per processor. Lowering the total cost of system.
Please don't misread the fact that one specialize multi-node system can now do some work once reserved for large systems as this system intends to or even could replaces all large single systems. Large systems still have many uses. Even if they didn't, they could (and probably will) be used as direct replacements for the current nodes of the Exadata system when some workloads fail to scale in a usual way.
I expect to see a lot more packaging of Oracle software with Sun hardware in the not to distant future.
Oracle and Sun are currently only offering this server with X4170 Database nodes and X4275 Storage nodes running Oracle Enterprise Linux. There does not, however, seem to be anything limiting the use of other x86 systems and there are plenty in the Sun arsenal. I also suspect that a Solaris x86 and Solaris SPARC versions are in the works if not already done. These will allow Oracle to take advantage of more of Sun technologies such as CMT and ZFS.
The Exadata storage nodes are not just used as RAID arrays but actually as subsystems that do some of the database work. They actively run queries on their portion of the compressed data, and return only relevant data to the database nodes. This helps eliminate unnecessary interconnect traffic. The interconnect is often a bottleneck of multi-node systems such as this, so any way of cutting down on traffic is most welcome. They are also using QDR InfiniBand and four PCIe cards with flash cache to accelerate workloads. Oracle has optimized it's database to use this flash, increasing its performance so much that they now allow OLTP and even mixed workloads.
OLTP in this type of system is quite distributive. It has traditionally been handled by vertically scaled systems, which add more processors in a single node versus adding more nodes to handle a larger workload. There are various technical details which made this necessary and congratulations to Oracle for overcoming them. What's the big deal here? Money. Smaller nodes typically cost less per processor. Lowering the total cost of system.
Please don't misread the fact that one specialize multi-node system can now do some work once reserved for large systems as this system intends to or even could replaces all large single systems. Large systems still have many uses. Even if they didn't, they could (and probably will) be used as direct replacements for the current nodes of the Exadata system when some workloads fail to scale in a usual way.
I expect to see a lot more packaging of Oracle software with Sun hardware in the not to distant future.
Bookmark
Email this
Comments (0)
Subscribe to this comment's feed
Write comment
