Earlier this month, Oracle announced the availability of the latest Exadata machine, the X8-2. As well as the option to swap in big 14 TB disks in older versions of Exadata that were shipped with far smaller disks, allowing these older systems to substantially increase there capacity.
Our AMIS resident Exadata expert Michael Huisman analyzed the key aspects of Oracle’s announcement.
The changes in specifications compared to X7 are not huge. The most eye catching change is the size of the disks: from 10 TB to 14 TB. Considering the fact that licence costs for Exadata are calculated based on number of disks, this means that for the same money, the capacity of Exadata is substantially increased.
Focusing on some details:
Compared to X7, the database nodes have a new CPU. It has the same number of cores (2x 24 per node) but a somewhat higher clockspeed: 2.4GHz vs. 2.1GHz in X7. The size of the memory has not changed: standard 384 GB per server with a maximum of 1.5 TB.
The inifiniband setup has stayed the same.
As mentioned, things have changed regarding the storage nodes. The disk size went up from 10 TB to 14 TB. The number of cores on the Storage Node went to 2x 16 per node, up from 2x 10 in X7. A slightly higher clockspeed: 2.3 GHz vs 2.2 GHz in X7. Memory and Flash cards stayed the same at 192 GB and 4x 6.4 TB respectively per storage node. All in all, the number number of IOPS is only slightly increased compared to X7.
A third type of storage node has been introduced: Storage Server XT. This is a storage node without flash cards and with less memory and only a single CPU. This type of node is intended for long term data storage for archiving purposes. It will cost considerably less than the regular storage nodes.
Check out this data sheet for the full specification overview: https://www.oracle.com/a/ocom/docs/engineered-systems/exadata/exadata-x8-2-ds.pdf
Disk Swap in older Exadata models
Michael points out a very interesting new option announced by Oracle along with Exadata X8-2: the option to swap the disks in older Exadata models to the new 14 TB disks. This allows customers to replace the disks in the storage nodes in their Exadata X4, X5, X6 and X7 models (not for the models prior to X4) with the new 14 TB disks. When the capacity of the current Exadata system is not enough for today’s needs, swapping disks is far cheaper than adding storage nodes. Adding new storage nodes is not attractive, for several reasons: the increased license costs is the main one and additionally you will probably not be able to use all space on the newly added disks. This is because ASM slices data across the same size on all disks; the smallest disk determines the space used on all disks, including far larger disks. Swapping disks allows you to have bigger disks in all storage nodes, leveraging disks (and the associated license costs) to the fullest. And you get to keep your old disks after swapping in the ones. With a little operation, these disks can be turned into standard hard disks that can be used in any standard rack.
As a little telling example: assume an existing Exadata X4 system – a quarter rack. It has three storage nodes with a total of 36 x 4 TB diskspace or 144 TB in totaal. After swapping the disks, this goes up to 504 TB in total. over three times as much. Without increased license costs – you only pay for the new disks.
The swap of the disks can be performed on line – no downtime – when certain conditions are met. This requires the latest release of the Exadata software, 19.2.0.0 in order to work with the firmware for the new 14TB disks. More information can be found in Oracle Support site note 1544637.1: https://support.oracle.com/epmos/faces/DocumentDisplay?id=1544637.1
For more details on upgrading your Exadata system with the new big disks or for advise on Exadata configuration and management, you can contact AMIS: info@amis.nl .
