White Paper EMC® XtremIO™ with MongoDB Validating XtremIO in MongoDB Environment EMC E-LabTM Verticals Engineering Group Abstract This white paper provides a reference architecture for deploying a MongoDB environment in an EMC XtremIO storage array. The paper details how MongoDB benefits from the advanced technical features of EMC XtremIO. March 2015 Copyright © 2015 EMC Corporation. All Rights Reserved. EMC believes the information in this publication is accurate as of its publication date. The information is subject to change without notice. The information in this publication is provided as is. EMC Corporation makes no representations or warranties of any kind with respect to the information in this publication, and specifically disclaims implied warranties of merchantability or fitness for a particular purpose. Use, copying, and distribution of any EMC software described in this publication requires an applicable software license. 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Part Number H14038 EMC XtremIO with MongoDB White Paper 2 Table of contents Executive summary............................................................................................................................... 4 Introduction.......................................................................................................................................... 5 Purpose ........................................................................................................................................... 5 Scope .............................................................................................................................................. 5 EMC XtremIO .................................................................................................................................... 5 System specification ................................................................................................................... 5 MongoDB ......................................................................................................................................... 7 Testing environment............................................................................................................................. 8 Server configuration ......................................................................................................................... 8 Software configuration ..................................................................................................................... 8 Benefits using XtremIO and MongoDB.................................................................................................. 9 Simplicity of management.............................................................................................................. 10 Scalable capacity and performance................................................................................................ 12 Scalable capacity and performance benefits MongoDB cluster expansion ................................. 12 Consistent performance ................................................................................................................. 14 Performance tests for MongoDB database operation in XtremIO ................................................ 14 Test summary ............................................................................................................................ 14 Test details................................................................................................................................ 14 Space efficient ............................................................................................................................... 18 Overall efficiency for competitive TCO........................................................................................ 19 Advanced data services ................................................................................................................. 20 XtremIO Snapshot ..................................................................................................................... 20 Clone MongoDB database in minutes with XtremIO Snapshot ................................................... 22 Create MongoDB replica set in minutes with XtremIO Snapshot ................................................ 23 Advanced data protection and high-availability ............................................................................. 24 Data-safe and hardware redundancy environment for MongoDB................................................ 25 NDU provides MongoDB service online upgrade ............................................................................. 25 Data at Rest Encryption provides data securing to MongoDB .......................................................... 25 Conclusion ......................................................................................................................................... 27 Summary ....................................................................................................................................... 27 References.......................................................................................................................................... 28 EMC XtremIO with MongoDB White Paper 3 Executive summary Redefining IT services to accommodate the requirements of data growth (Big Data) and transforming them from 2nd platform to 3rd platform has become a challenge for enterprise IT managers. The balance between on-demand scaling of capacity and performance and the total cost of ownership (TCO) drives enterprise vendors and customers to seek ways to utilize different types of technologies for archiving. From a database perspective, next-generation databases, such as NoSQL database, address some of the challenging points: to be non-relational, distributed, opensourced, and horizontally scalable. MongoDB, recognized as one of the leading NoSQL databases, offers a choice for customers using a next-generation database. From a storage perspective, flash storage is an attractive method to boost I/O performance in the data center. However, it has always come at a price, both in high costs and loss of capabilities such as scalability, high availability, and enterprise features. EMC® XtremIO™ is a 100% flash-based, scale-out enterprise storage array that delivers not only high levels of performance and scalability, but also brings new levels of ease-of-use to SAN storage, while offering advanced features that have never before been possible. From the beginning, XtremIO's ground-up all-flash array design was created for maximum performance and consistent low latency response times., It has enterprisegrade, high-availability features, real-time inline data reduction that dramatically lowers costs, and advanced functions such as thin provisioning, tight integration to VMware, snapshots, volume clones, and superb data protection. This achieves a competitive cost of ownership. The product architecture addresses all the requirements for flash-based storage, including achieving longevity of the flash media, lowering the effective cost of flash capacity, delivering performance and scalability, providing operational efficiency, and delivering advanced storage array functionality. This white paper provides a broad introduction to deploying a MongoDB environment in an EMC XtremIO storage array. EMC XtremIO with MongoDB White Paper 4 Introduction Purpose This document provides reference architecture for deploying MongoDB 2.6.7 on the EMC XtremIO storage array. Scope This document is intended for use by pre-sales, sales engineers and customers who want to deploy the EMC XtremIO storage array in a MongoDB environment. EMC XtremIO The XtremIO storage array is an all-flash system, based on scale-out architecture. The system uses building blocks, called X-Bricks, which can be clustered together to grow performance and capacity as required. Figure 1. EMC XtremIO Storage Array The system operation is controlled via a stand-alone, dedicated Linux-based server, called the XtremIO Management Server (XMS). Each XtremIO cluster requires its own XMS host, which can be either a physical or a virtual server. The array continues operating if it is disconnected from the XMS, but cannot be configured or monitored. XtremIO's array architecture is specifically designed to deliver the full performance potential of flash, while linearly scaling all resources such as CPU, RAM, SSDs, and host ports in a balanced manner. This allows the array to achieve any desired performance level, while maintaining consistency of performance that is critical to predictable application behavior. The XtremIO Storage System provides a very high level of performance that is consistent over time, system conditions, and access patterns. It is designed for true random I/O. System specification EMC XtremIO supports up to six X-Bricks in a cluster (available from version 3.0). This will continue to increase in subsequent releases of the XtremIO Operating System. EMC XtremIO with MongoDB White Paper 5 The following diagram below shows a single X-Brick specification: Figure 2. Single X-Brick specification An X-Brick is the basic building block of an XtremIO array. The following table lists the feature and specifications of each X-Brick: Table 1. X-Brick features and specifications EMC XtremIO with MongoDB White Paper 6 MongoDB MongoDB is recognized as one of the leading NoSQL databases, with better development experience and higher development productivity. Fortune 500 and startup companies choose MongoDB to accelerate time-to-market, transform the customer experience, enhance efficiency, and reduce cost. MongoDB is an open-source database used by companies of all sizes, across all industries, and for a wide variety of applications. It is a cross-platform documentoriented schema-less database that uses a flexible data model. MongoDB supports search by field, range queries, regular expression searches. Queries can return specific fields of documents and also include user-defined JavaScript functions. Any field in a MongoDB document can be indexed; secondary indices are also available. MongoDB is built for performance, high availability, and scalability. Sharding and replica set are two types of MongoDB clusters. Sharding splits the database into multi-pieces for load balance. Replica set is similar to replication and used for faulttolerance. For example, A splits to A1, A2, A3, A4 and then each subcomponent replicates: (A1, A1, A1), (A2, A2, A2), (A3, A3, A3), (A4, A4, A4). These two types of clusters are usually deployed together in a production environment to archive both load-balance and high availability. By deploying sharding and replica set, MongoDB can scale from one single server to many, providing high performance in archiving, enterprise-grade reliability, and operational flexibility. EMC XtremIO with MongoDB White Paper 7 Testing environment The diagram below represents the hardware configuration in this paper Server configuration One Cisco UCS C460 server was used for testing. Component Processor Memory HBA SAN Switches Description 4 intel Xeon E704830 @ 2.13 GHz 128 GB 8 Gbps 1 port FC HBA x 4 Brocade DCX8510 Software configuration Component EMC XtremIO MongoDB Operating System Description Release 3.0.1 Release 2.6.7 CentOS Release 7.0 x86_64 Note: For detail host configurations, refer to the Host Configuration Guide for XtremIO Versions 2.2.x - 3.0.1 at http://support.emc.com EMC XtremIO with MongoDB White Paper 8 Benefits using XtremIO and MongoDB To date, most MongoDB deployments use Direct Attached Storage (DAS) to hold the datasets, primarily because DAS was seen as a cost effective and simple solution. However, requirements from performance-sensitive applications call for ways to leverage the performance benefit on PCIE Solid State Disks (SSDs). In this case, capital and operation expense associated with SSD cards have become a serious issue. For this reason, there are an increased number of customers deriving real benefit from deploying MongoDB on an All-Flash-Array (AFA), thus obtaining competitive total cost of ownership (TCO). EMC XtremIO storage array offers an extraordinary choice for customers who want the following benefits: • • Simplicity of management Scalable capacity and performance • Consistent performance • • Space efficient Advanced data services • Advanced data protection and high availability • • Non-disruptive upgrade Data at Rest Encryption This paper discusses each of these advantages in more detail. EMC XtremIO with MongoDB White Paper 9 Simplicity of management XtremIO is very simple to configure and manage, and there is no need for tuning or extensive planning. With XtremIO, the user does not need to choose between different RAID options in order to optimize the database. Once the system is initialized, the XDP is already configured as a single redundancy group. All the user data is spread across all the X-Bricks. There is also no tiering and performance tuning. All I/Os are treated equally. All volumes, when created, are mapped to all ports (FC and iSCSI) and there is no storage tiering in the array. This eliminates the need for manual performance tuning and optimization settings and makes the system easy to manage, configure, and use. XtremIO provides: • • Minimum planning - No RAID configuration - Minimal sizing effort for cloning/snapshots No tiering - • Single tier, all-flash array No performance tuning - Independent of I/O access pattern, cache hit rates, tiering decisions, etc. The system GUI is implemented using a Java client. The GUI client software communicates with the XMS, using standard TCP/IP protocols, and can be used in any location that allows the client to access the XMS. The GUI provides easy-to-use tools for performing most of the system operations (certain management operations must be performed using the CLI). Additionally, operations on multiple components, such as creating multiple volumes, can only be performed using the GUI. The following figure shows how the GUI can be used to map Volumes to Initiator Groups in a few simple steps. Figure 3. System GUI EMC XtremIO with MongoDB White Paper 10 The following figure shows the GUI's Dashboard to enable the user to monitor the system's storage, performance, and alerts. Figure 4. GUI Dashboard to monitor storage, performance, alerts The following figure shows the GUI’s Dashboard enabling the user to monitor the hardware status. Figure 5. GUI Dashboard to monitor hardware status EMC XtremIO with MongoDB White Paper 11 Scalable capacity and performance The XtremIO storage system is based on scale-out architecture. The system begins with a single building block, called an X-Brick. When additional performance and capacity are required, the system scales out by adding X-Bricks. Performance scales linearly, ensuring that two X-Bricks supply twice the IOPS, four X-Bricks supply four times the IOPS and six X-Bricks supply six times the IOPS of the single X-Brick configuration. Latency remains consistently low as the system scales out. Note: Active controllers vary from 2 to 12 along with the scale-out architecture. Figure 6. X-Brick scale-out architecture Scalable capacity and performance benefits MongoDB cluster expansion Along with the data growth, scalability on both capacity and performance is strongly needed. From a database perspective, MongoDB has provided a method for storing data across multiple machines, called sharding. MongoDB uses sharding to support deployments with very large data sets and high throughput operations. EMC XtremIO with MongoDB White Paper 12 Figure 7. MangoDB sharding example For non-scale-out all-flash arrays, the performance benefit from SSD degrades with the growth of capacity. Sometimes the controller becomes a bottleneck when more and more SSDs are added into the system. With the scale-out architecture of EMC XtremIO, customers can scale their storage easily, meeting the requirements for MongoDB cluster, and obtaining both capacity and performance. Figure 8. XtremIO scale-out architecture EMC XtremIO with MongoDB White Paper 13 Consistent performance With the benefits of flash-optimized algorithms and active-active controllers, XtremIO provides consistent performance under any workloads. This performance also scales linearly with the scales of X-Brick Cluster. The following tests illustrated the consistent performance XtremIO provides in a cluster of two X-Bricks in a MongoDB environment. Performance tests for MongoDB database operation in XtremIO To prove XtremIO can offer consistent performance with low latency in different types of workloads, E-Lab processed two test scenarios, utilizing MongoPerf to simulate MongoDB operations on the LUN that is provisioned by EMC XtremIO storage array. MongoPerf is a tool provided by MongoDB along with the database installation binary. It is a utility to check disk I/O performance independently of MongoDB, test random disk I/O, and presents the results. Test summary Test 1: Simulate write MongoDB database operation on 1TB test file nThreads:16,fileSizeMB:1000000, mmf:true, r:false, w:true Test 2: Simulate mixed MongoDB database operation on 1TB test file nThreads:16,fileSizeMB:1000000, mmf:true, r:true, w:true Tests result: Test Scenario IOPS in LUN Latency DB Operations/s Test 1 50,000 < 0.25 ms 25,000 Test2 55,000 < 0.25 ms 45,000 The test results prove that under the benefits of all-flash, scale-out architecture, and other advanced features, LUNs provisioned from an EMC XtremIO storage array can provide consistent performance with extremely low latency. These benefits redefine the method of database deployment. Storage admins and DBAs no longer need to consider storage tuning or striping the I/O load to different volumes to archive a better IOPS and reasonable latency. They can now put more focus on meeting the challenge and on the increasingly rapid changes of requirements of different types of applications. Test details Test scenario 1: Simulate write MongoDB database operations by MongoPerf MongoPerf runs with the following parameters on MongoDB LUN: nThreads:16,fileSizeMB:1000000, mmf:true, r:false, w:true EMC XtremIO with MongoDB White Paper 14 Inflating test file Figure 9. LUN Bandwidth in MB/s during inflating the 1000 GB test file Under the benefits of multi-active controllers with all active paths, the bandwidth during inflating 1000GB test file reaches nearly 2000 MB/s. Simulating DB operations on the testing file Figure 10. Volume IOPS during the DB operations EMC XtremIO with MongoDB White Paper 15 Figure 11. LUN Latency in microsecond during the DB operations Test scenario 2: Simulate Mixed MongoDB database operations by MongoPerf MongoPerf runs with the following parameters on MongoDB LUN: nThreads:16,fileSizeMB:1000000, mmf:true, r:true, w:true Inflating Test File Figure 12. LUN Bandwidth in MB/s during inflating the 1000 GB test file EMC XtremIO with MongoDB White Paper 16 Under the benefits of multi-active controllers with all active paths, the bandwidth during inflating 1000GB test file reaches nearly 2000 MB/s. Simulating DB operations on the testing file Figure 13. Volume IOPS during the DB operations Figure 14. LUN Latency in microsecond during the DB operations EMC XtremIO with MongoDB White Paper 17 Space efficient EMC XtremIO offers the following features for customers to minimize the storage costs and enhance smart usage of SSD capacity. • Natural Thin Provisioning XtremIO storage is inherently thin-provisioned, using a small internal block size. This provides fine-grained resolution for the thin provisioned space. All volumes in the system are thin provisioned, meaning that the system consumes capacity only when it is actually needed. XtremIO determines where to place the unique data blocks physically inside the cluster after it calculates their fingerprint IDs. Therefore, it never pre-allocates or thickprovisions storage space before writing. As a result of XtremIO's content-aware architecture, blocks can be stored at any location in the system (and only metadata is used to refer to their locations) and the data is written only when unique blocks are received. Therefore, unlike thin provisioning with large disk-oriented architecture, with XtremIO there is no space creeping and no garbage collection. Furthermore, the issue of volume fragmentation over time is not applicable to XtremIO (as the blocks are scattered all over the random-access array) and no defragmentation utilities are needed. XtremIO's inherent thin provisioning also enables consistent performance and data management across the entire life cycle of the volumes, regardless of the system capacity utilization or the write patterns to the system. • Inline Data Reduction - Inline Data Deduplication Inline data deduplication is the removal of redundancies from data before it is written to the flash media. XtremIO automatically and globally deduplicates data as it enters the system. Deduplication is performed in real-time and not as a postprocessing operation. With XtremIO, there are no resource-consuming background processes and no additional reads/writes (which are associated with post-processing). Therefore, it does not negatively affect performance of the storage array, does not waste the available resources that are allocated for the host I/O, and does not consume flash wear cycles. - Inline Data Compression Inline Data Compression is the compression of the already deduplicated data before it is written to the flash media. XtremIO automatically compresses data after all duplications have been removed. This ensures that the compression is performed only for unique data blocks. Data compression is performed in real-time and not as a post-processing operation. The nature of the data set determines the overall compressibility rate. The compressed data block is then stored on the array. EMC XtremIO with MongoDB White Paper 18 Figure 15. Example of a 6:1 Total Inline Data Reduction Overall efficiency for competitive TCO With the benefits of “Natural Thin Provisioning” and “Inline Data Reduction” in XtremIO, the array used in this document totally provisioned 88.348 TB (including the volume for MongoDB) in capacity of volumes to different hosts, with 27.083 TB used and it only consumed 3.98 TB physical capacity. The overall capacity efficiency is 22:1 in this testing environment. Figure 16. Overall efficiency example Note: For more information on Data Reduction, refer to Introduction to the EMC XtremIO Storage Array at http://support.emc.com. EMC XtremIO with MongoDB White Paper 19 Advanced data services XtremIO provides advanced data services for MongoDB to protect against corruption as well as allowing parallel processing such as testing new versions, rolling back, etc. XtremIO Snapshot XtremIO snapshots are created by capturing the state of data in volumes at a particular point in time and allowing users to access that data when needed, even when the source volume has changed. XtremIO snapshots are inherently writeable, but may be mounted read-only to maintain immutability. Snapshots can be taken from either the source or any snapshot of the source volume. Snapshots can be used in a number of use cases, including: • Logical corruption protection XtremIO allows the creation of frequent snapshots (based on the desired RPO intervals) and their use in recovering any logical data corruption. The snapshots can be kept in the system as long as they are needed. If a logical data corruption occurs, snapshots of an earlier application state (prior to logical data corruption) can be used to recover the application to a known good point in time. • Backup It is possible to create snapshots to be presented to a backup server/agent. This can be used in order to offload the backup process from the production server. • Development and testing The system enables the user to create snapshots of the production data, create multiple (space-efficient and high-performance) copies of the production system and present them for development and testing purposes. • Clones With XtremIO, it is possible to achieve clone-like capabilities by using persistent writable snapshots. They can be used in order to present a clone of the production volume to multiple servers. Performance of the clone will be identical to that of the production volume. • Offline processing Snapshots can be used as a means to offload the processing of data from the production server. For example, if it is necessary to run a heavy process on the data (which can affect the production server's performance), it is possible use snapshots to create a recent copy of the production data and mount it on a different server. The process can then be run (on the other server) without consuming the production server's resources. EMC XtremIO with MongoDB White Paper 20 Figure 17. XtremIO Snapshot Compared to traditional snapshot, XtremIO Snapshot provides the benefits listed in following table. Table 2. XtremIO Snapshot comparisons Note: For more information on XtremIO Snapshot, refer to Introduction to the EMC XtremIO Storage Array at http://support.emc.com. EMC XtremIO with MongoDB White Paper 21 Clone MongoDB database in minutes with XtremIO Snapshot Customer can utilize XtremIO Snapshot to clone the database for backup or for development or testing. The performance of the clone will be identical to that of the production volume. Cloning a database from one node to another can be done by following the four following steps. Note: To obtain an application-consistent stat, all necessary operations need to be done in the database and operating system before taking the snapshot. Step 1: Take and name a snapshot on the LUN(s) hosting the database. EMC XtremIO with MongoDB White Paper 22 Step 2: Connect the snapshot to destination host using the following four clicks: Step 3: Scan and mount the snapshot on the destination host. For example, in Linux you can use: # rescan-scsi-bus.sh -i -r Edit /etc/fstab add the correct content /dev/mapper/mpathb1 /mongodb ext4 discard,noatime 1 2 #mount /mongodb Step 4: Start the database pointing dbpath to the snapshot. Mongod --dbpath /mongodb/data --logpath /mongodb/log/config.log --port 27017 -fork A cloned MongoDB is created. Customers can utilize this cloned MongoDB for developing and testing, parallel with production. Create MongoDB replica set in minutes with XtremIO Snapshot While MongoDB performance bottleneck comes from server configuration, DBAs can easy covert the MongoDB into clusters, such as a replica set under the help of XtremIO snapshot. EMC XtremIO with MongoDB White Paper 23 By cloning the database using Snapshot and performing necessary operations in MongoDB, a replica set can be created in minutes. Due to the XtremIO advanced Snapshot, the performance between the cloned and the source are identical. Figure 18. Closing the database using Snapshot Note: For details on creating sharding or replication set in MongoDB, refer to the MongoDB Manual at http://docs.mongodb.org. Advanced data protection and high-availability XtremIO utilizes a proprietary flash-optimized data protection algorithm, which is dedicated to fast rebuild and all-around protection and performs more efficiently than traditional RAID types. The method achieves RAID-6-like protection level while enabling performance that is superior to any existing RAID algorithms. It results in fewer writes to flash media for data protection purposes. Benefiting from the partial stripes approach, it requires very little capacity overhead for data protection and metadata space and does not require dedicated spare drives for rebuilds. Any free space available in the array can be utilized for failed drive reconstructions. Table 3. Flash-optimized data protection algorithm EMC XtremIO with MongoDB White Paper 24 XtremIO's Active-Active architecture is designed to ensure maximum performance and consistent latency. The system includes a self-healing mechanism that attempts to recover from any failure and resume full functionality. An attempt to restart a failed component is performed once before a failover action. Storage Controller failover is carried out as the last resort. Based on the nature of the failure, the system attempts to failover the relevant software component, while maintaining the operation of other components, thus minimizing the performance impact. The whole Storage Controller fails over only if recovery attempts are not successful or if the system must act in the best interest of protecting against data loss. Data-safe and hardware redundancy environment for MongoDB A database is always one of the most important and valuable data assets in company. Putting a database into a safe, fault- tolerant environment is the highest priority, above any other factors. The advanced data protection and high availability in EMC XtremIO provides a datasafe, space efficient, fault tolerant, and hardware redundant environment for a customer’s database. Note: For more information on advanced data protection and high availability, refer to Introduction to the EMC XTREMIO Storage Array, at http://support.emc.com. NDU provides MongoDB service online upgrade During Non-Disruptive Upgrades (NDU) of the XtremIO Operating System, the system performs the upgrade procedure on a live cluster, updates all Storage Controllers in the cluster, and restarts the application in a process that takes less than 10 seconds. Since the underlying Linux Kernel is active throughout the upgrade process, the hosts do not detect any path disconnection during the application (GUI) restart period. In the rare case of a Linux kernel or firmware upgrade, it is possible to upgrade the XtremIO All Flash Array without any service interruption and without any risk of data loss. The NDU procedure is launched from the XtremIO Management Server and is able to upgrade the XtremIO software and the underlying operating system and firmware. During Linux/firmware NDU, the system automatically fails over a component and upgrades its software. After completing the upgrade and verifying the component's health, the system fails back to it and the process repeats itself on other components. During the upgrade process the system is fully accessible, no data is lost, and the performance impact is kept to minimum. Data at Rest Encryption provides data securing to MongoDB Data at Rest Encryption (DARE) provides a solution to securing critical data even when the media is removed from the array. XtremIO arrays utilize a high performance inline encryption technique to ensure that all data stored on the array is unusable if the SSD media is removed. This prevents unauthorized access in the event of theft or loss during transport, and makes it possible to return/replace failed components containing sensitive data. EMC XtremIO with MongoDB White Paper 25 Figure 19. Data At Rest Encryption Note: For more information on advanced data protection and high availability, refer to Introduction to the EMC XTREMIO Storage Array, at http://support.emc.com. EMC XtremIO with MongoDB White Paper 26 Conclusion Summary By deploying EMC XtremIO storage array into next generation database environments, like MongoDB, customer can get the following benefits: • Leveraging advance revolutionary architecture for all-SSD storage subsystems XtermIO has developed an advanced revolutionary architecture, which is optimized for all-SSD enterprise storage subsystems. XtremIO offers a rich set of features that leverage and optimize the SSD media capabilities and have been especially designed to provide unparalleled solutions for enterprise customers' needs and requirements. • Accelerating database and competitive TCO XtremIO's features include truly-scalable solutions (buy additional capacity and performance when needed), high performance with hundreds of thousands of IOPS, constant sub-millisecond low latency, content-aware Inline Data Reduction, high availability, thin provisioning, and snapshots. • Efficient and powerful data protection XtremIO also offers a unique patent-protected scheme that leverages the SSD media characteristics to provide an efficient and powerful data protection mechanism which can protect the data against two simultaneous and multiple consecutive failures. • Ease of management XtremIO incorporates a comprehensive, intuitive and user-friendly interface which includes both GUI and command line modes and is designed for easeof-use while enabling efficient system management. XtremIO provides the perfect solution for all-SSD enterprise SAN storage while offering a superior total cost of ownership solution for its customers. EMC XtremIO with MongoDB White Paper 27 References The documents referred in this paper are listed below and can be found at http://support.emc.com. • Introduction to the EMC XtremIO Storage (Ver. 3.0) • Host Configuration Guide for XtremIO Versions 2.2.x - 3.0.1 • MongoDB Manual 2.6 EMC XtremIO with MongoDB White Paper 28
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