SAP HANA Tiering: The Pressures of Data Growth
Fri, 01 May 2020 14:24:20 -0000|
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“Data growth is accelerating!” Quotes like this appear frequently in studies, papers, and blogs. You will not find more data growth quotes in this blog article, however, because I think it is more interesting to look at this from a data management investment policy perspective. A data management investment policy has similar benefits to a corporate travel investment policy—the goal is to efficiently maximize the bottom line. In most customer accounts, the SAP HANA licensing investment happens early and the business must maximize the benefits in the long term. First cost is not the sole driver because volume, variety, veracity, and velocity are all considerations when a company is looking for a strategy. Evaluating a data management investment policy for the long term can be complex. SAP provides Native Storage Extensions (NSE) to address both cost pressures and the intelligent placement of data over time.
SAP HANA with NSE offers the functionality of tiering data using different storage solutions based on the age of the data. The NSE data management policy categorizes data into three classes: hot, warm, or cold. This blog post focuses on the hot and warm data tiers. Hot data can use both volatile and nonvolatile memory, as follows:
- DRAM: DRAM is the fastest storage media. DRAM is volatile, however, meaning the data must be loaded into memory on restart of the database or server.
- PMEM: Persistent Memory (or PMEM) is faster than SSD storage but not as fast as DRAM. PMEM is also nonvolatile memory, meaning the data does not have to be loaded into memory on restart of the database or server. PMEM is used for the SAP HANA Fast Restart option.
SAP HANA on-premises Native Storage Extension
If you are interested in learning more about maximizing your data management investment strategy, the SAP HANA TDI on Dell EMC PowerEdge Servers Validation Guide provides detailed configurations. The hot data tier both drives the fastest performance and is the most expensive tier (hardware + SAP HANA licensing + annual support). Maximizing the performance-to-cost trade-off of hot data placement requires consideration of two factors:
- Keep actively used data that is critical to the business in the hot data tier
- Migrate less frequently used data out of the hot data tier to sustain costs
The first consideration is a performance guideline for when the responsiveness of the database and applications is at a premium for the business. Data that is less frequently used can be placed in the warm tier to minimize the impact on queries on the hot data tier. Another benefit is related to SAP HANA restarts. For example, planned maintenance events involving Linux operating system or SAP HANA database updates can require a restart. An SAP HANA system with NSE could have less data in the hot tier compared to the same SAP HANA system without NSE, thus improving restart times.
NOTE: SAP HANA also has a Fast Restart Option that uses file storage to speed up restarts. Fast Restart leverages PMEM to accelerate file storage access, significantly reducing the start time of the database. SAP HANA Fast Restart applies to scenarios in which only SAP HANA is restarted and not the operating system.
The second consideration is an avoidance guideline that sustains existing investments while mitigating additional ones. Success could be defined as a strategy in which performance increases with each new server generation while SAP HANA costs remain constant if the size of the hot data tier remains the same. The business impact is a continual increase in performance combined with efficiently maximizing the bottom line.
The warm data tier is for less frequently accessed data that occasionally resides in SAP HANA memory. If kept in memory, warm data accelerates costs, mainly through the additional licensing that is needed to increase the memory size. To mitigate the impact of rapid data growth, maximize the usage of the warm data tier. Keep in mind that the warm data tier is limited to four times the size of the hot data tier. For example, a hot data tier of 1 TB means the warm data tier can be up to 4 TB. The warm data tier also cannot exceed 10 TB in size. The 10 TB maximum is a first-release restriction.
Data in the warm tier is transactionally consistent with the hot data tier. This means that the warm data tier must be protected in conjunction with the hot data tier so that the entire database backup is consistent. While the hot and warm data tiers are transactionally consistent, they differ in how data is loaded into memory. The hot data tier is ”column loadable,” meaning the columnar tables are loaded into memory. In contrast, the warm data tier is “page loadable,” meaning granular portions of data are loaded into memory or partially in memory. The page-loadable design has two key benefits for the warm data tier:
- It does not significantly impact the memory footprint.
- It does not significantly impact the start time of the database.
Use of the warm data tier depends on the SAP HANA NSE buffer cache. This buffer cache is enabled by default and is initially sized as 10 percent of SAP HANA memory (for the sizing reference, see the SAP HANA Administration Guide for SAP HANA Platform 2.0 SPS 04). For example, the NSE buffer size is recommended to be at least 12.5 percent of the total size of the warm data tier. You can modify the NSE buffer cache size by using the ALTER SYSTEM ALTER CONFIGURATION command.
Warm Data Tier
Overall, use of the warm data tier enables customers to balance fast performance with increased data volumes while minimizing cost, thus achieving greater value. Customers have the flexibility to design an amazingly fast warm data tier with storage I/O latencies measured in microseconds, narrowing the difference between the hot and warm data tiers in terms of performance.
Dell Technologies has a team of experienced SAP HANA experts that can assist with accurate sizing and design of an infrastructure solution for your databases. Our goal is to work closely with you to maximize the value of NSE and create an extremely fast warm data tier that narrows the performance gap with the hot data tier. Your Dell Technologies representative can put you in contact with one of our SAP HANA experts.
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Mon, 30 Mar 2020 15:24:55 -0000|
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Two new all-NVMe VxRail platforms deliver highest levels of performance
December 11, 2019
If you have not been tuned into the VxRail announcements at VMworld Barcelona last month, this is news to you. VxRail is adding more performance punch to the family with two new all-NVMe platforms. The VxRail E Series 560N and P Series 580N, with the 2nd Generation Intel® Xeon® Scalable Processors, offer increased performance while enabling customers to take advantage of decreasing NVMe costs.
Balancing workload and budget requirements, the dual-socket E560N provide a cost-effective, space-efficient 1U platform for read-intensive workloads and other complex workloads. Configured with up to 32TB of NVMe capacity, the E560N is the first all-NVMe 1U VxRail platform. Based on the PowerEdge R640, the E560N can run a mix of workloads including data warehouses, ecommerce, databases, and high-performance computing. With support for Nvidia T4 GPUs, the E560N is also equipped to run a wide range of modern cloud-based applications, including machine learning, deep learning, and virtual desktop workloads.
Built for memory-intensive high-compute workloads, the new P580N is the first quad-socket and also the first all-NVMe 2U VxRail platform. Based on the PowerEdge R840, the P580N can be configured with up to 80TB of NVMe capacity. This platform is ideal for in-memory databases and has been certified by SAP for SAP HANA. The P580N provides 2x the CPU compared to the P570/F and offers 25% more processing potential over virtual storage appliance (VSA) based 4-socket HCI platforms that require a dedicated socket to run (VSA).
The completion of the SAP HANA certification for the P580N which coincides with the P580N’s general availability demonstrates the ongoing commitment to position VxRail as the HCI platform of choice for SAP HANA solutions. The P580N provides even more memory and processing power than the SAP HANA certified P570F platform. An updated Validation Guide for SAP HANA on VxRail will be available in early January on the Dell EMC SAP solutions landing page for VxRail.
For more information about VxRail E560N and P580N, please check out the resources below:
Automate and standardize SAP operations using Dell EMC ESI for stoage integration
Thu, 17 Sep 2020 15:24:50 -0000|
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Enterprise SAP landscapes can have dozens of interrelated instances when you include all the nonproduction systems that are used for development, testing, training, and sandbox experimentation. SAP Landscape Management (LaMa) software combined with the Dell EMC Enterprise Storage Integrator (ESI) for SAP LaMa simplifies management of these complex SAP environments by using advanced storage-based local and remote replication services that are integrated into Dell EMC storage systems.
Dell Technologies offers the SAP enabled enterprise one of the industry’s broadest portfolios of storage array options. All the storage systems that are listed in this blog post are supported by Dell EMC ESI for SAP LaMa software for simplifying landscape management. Customers can choose a solution from any of the Unity, Unity XT, VMAX3, and PowerMax storage array models and get integration with SAP LaMa to improve management of their SAP systems. Unity XT arrays are midrange storage platforms that are designed for performance, efficiency, and data protection. PowerMax arrays are larger storage platforms that accelerate applications with end-to-end NVMe flash storage, global deduplication and compression, and data protection. The following table shows the storage arrays that ESI supports:
Table 1: ESI supported storage systems
Unified SAN and NAS
SAP LaMa is an automation and orchestration solution that replaces manual or scripted processes for creating clones, copies, and related refresh activities. Simplified landscape management provides key business benefits, including improved service quality and the capability to new drive business innovation. SAP LaMa combined with Dell EMC ESI provides a single pane of glass for operations such as SAP system relocation, snapshots, provisioning processes, and more. These capabilities increase manageability and promote business agility by enabling administration teams to address rapidly changing organizational demands. Dell EMC supports SAP LaMa in physical, virtual, and cloud technologies, providing a single pathway to manage most landscape configurations.
Examples of improved operational capabilities include:
- SAP LaMa System Relocation—This operation enables relocation of an SAP system from the original location to another host that is recognized by SAP LaMa. System relocation operations are useful when the primary SAP server system requires scheduled maintenance or an upgrade. The entire relocation operation is automated, with ESI enabling administrators to be quickly up and running on another server. The following configurations are supported:
- Physical-to-physical (P2P) bare-metal to bare-metal
- Physical-to-virtual (P2V) bare-metal to VMware virtual using Raw Device Mapping (pRDMs)
- Virtual-to-virtual (V2V) VMware VMDK disks from one VM to another
- Managed SAP LaMa Managed snapshots—This operation enables “snap copying” of all source volumes from an SAP system by using a single API call to maintain storage consistency. Storage snapshots are a low-overhead point-in-time image of source volumes on a storage array. Customers can use these snapshots in place of full copies for many management tasks. For example, PowerMax and VMAX arrays use SnapVX to create a consistent image of SAP system volumes. Snapshots are more efficient than full copies because only the data changes between the source volumes and the images are copied to the “snap copy” volumes. For many SAP landscape management operations, PowerMax and VMAX snapshots consume only a small fraction of the space that is used on the primary SAP system storage array.
- SAP LaMa system provisioning
- System Clone—This operation duplicates a system that is currently running or a previously created managed snapshot. The duplicated clone and source systems have identical system IDs. The clone is isolated on a dedicated network to prevent application users from connecting to the wrong system by mistake. The default configuration for system clones that are created on Dell EMC storage arrays is to use space-efficient snapshots of the source volumes (space savings). By selecting the ‘Full Copy’ option, customers can also create a full clone that doubles the storage space that is consumed.
- System Copy—This operation creates a copy of an existing SAP system with a new unique SAP system ID, host name, and IP address. A system copy is useful when the business needs a copy of either a production or nonproduction system for quality assurance, development, or testing. The two key differences with a system clone are the creation of a new identity (ID, hostname, IP) when using a copy operation and the use of new storage volumes and full space allocations by the copy.
- System Refresh—This operation refreshes either a complete or used part of an existing system, as specified by the user. System refresh procedures enable three options: Refresh system, Refresh database (database only), and Restore-based refresh. Refreshing an existing system is frequently faster than creating a copy. Also, the system refresh procedure enables application teams to continue using the SAP system that they are familiar with, reducing complexity. The restore-based refresh procedure integrates with the leading Dell EMC Data Protection solutions such as PowerProtect Application Direct database agents and Data Domain with DDBoost.
Figure 1: Dell EMC ESI integration with SAP Landscape Management
In addition to the preceding scenarios, customers can streamline operations such as monitoring and data protection by enabling Dell EMC integration with SAP LaMa. For example, with data protection integration, you can perform on-demand and scheduled backups of the SAP system. By using Unity, Unity XT, VMAX3, and PowerMax ESI integration, customers can automate most system operations for SAP. Further, the opportunity for increased storage savings through efficient storage snapshots means that SAP customers can have a greater number of SAP systems consuming less overall space on their Dell EMC storage systems.
The Dell Technologies SAP site is the place to start learning about the features and capabilities that both Dell EMC storage and PowerEdge servers offer. If you are interested in more technical material, see the Enterprise Storage Integrator for SAP Landscape Management End-user Guide 8.0 on the Dell Technologies support site.