هذه الصفحة غير متوفرة حاليًا بلغتك المحلية. نحن نعمل جاهدين على إضافة المزيد من اللغات. شاكرين تفهمك ودعمك المستمر لنا.

Compute
Elastic Cloud Server
Huawei Cloud Flexus
Bare Metal Server
Auto Scaling
Image Management Service
Dedicated Host
FunctionGraph
Cloud Phone Host
Huawei Cloud EulerOS
Networking
Virtual Private Cloud
Elastic IP
Elastic Load Balance
NAT Gateway
Direct Connect
Virtual Private Network
VPC Endpoint
Cloud Connect
Enterprise Router
Enterprise Switch
Global Accelerator
Management & Governance
Cloud Eye
Identity and Access Management
Cloud Trace Service
Resource Formation Service
Tag Management Service
Log Tank Service
Config
OneAccess
Resource Access Manager
Simple Message Notification
Application Performance Management
Application Operations Management
Organizations
Optimization Advisor
IAM Identity Center
Cloud Operations Center
Resource Governance Center
Migration
Server Migration Service
Object Storage Migration Service
Cloud Data Migration
Migration Center
Cloud Ecosystem
KooGallery
Partner Center
User Support
My Account
Billing Center
Cost Center
Resource Center
Enterprise Management
Service Tickets
HUAWEI CLOUD (International) FAQs
ICP Filing
Support Plans
My Credentials
Customer Operation Capabilities
Partner Support Plans
Professional Services
Analytics
MapReduce Service
Data Lake Insight
CloudTable Service
Cloud Search Service
Data Lake Visualization
Data Ingestion Service
GaussDB(DWS)
DataArts Studio
Data Lake Factory
DataArts Lake Formation
IoT
IoT Device Access
Others
Product Pricing Details
System Permissions
Console Quick Start
Common FAQs
Instructions for Associating with a HUAWEI CLOUD Partner
Message Center
Security & Compliance
Security Technologies and Applications
Web Application Firewall
Host Security Service
Cloud Firewall
SecMaster
Anti-DDoS Service
Data Encryption Workshop
Database Security Service
Cloud Bastion Host
Data Security Center
Cloud Certificate Manager
Edge Security
Situation Awareness
Managed Threat Detection
Blockchain
Blockchain Service
Web3 Node Engine Service
Media Services
Media Processing Center
Video On Demand
Live
SparkRTC
MetaStudio
Storage
Object Storage Service
Elastic Volume Service
Cloud Backup and Recovery
Storage Disaster Recovery Service
Scalable File Service Turbo
Scalable File Service
Volume Backup Service
Cloud Server Backup Service
Data Express Service
Dedicated Distributed Storage Service
Containers
Cloud Container Engine
SoftWare Repository for Container
Application Service Mesh
Ubiquitous Cloud Native Service
Cloud Container Instance
Databases
Relational Database Service
Document Database Service
Data Admin Service
Data Replication Service
GeminiDB
GaussDB
Distributed Database Middleware
Database and Application Migration UGO
TaurusDB
Middleware
Distributed Cache Service
API Gateway
Distributed Message Service for Kafka
Distributed Message Service for RabbitMQ
Distributed Message Service for RocketMQ
Cloud Service Engine
Multi-Site High Availability Service
EventGrid
Dedicated Cloud
Dedicated Computing Cluster
Business Applications
Workspace
ROMA Connect
Message & SMS
Domain Name Service
Edge Data Center Management
Meeting
AI
Face Recognition Service
Graph Engine Service
Content Moderation
Image Recognition
Optical Character Recognition
ModelArts
ImageSearch
Conversational Bot Service
Speech Interaction Service
Huawei HiLens
Video Intelligent Analysis Service
Developer Tools
SDK Developer Guide
API Request Signing Guide
Terraform
Koo Command Line Interface
Content Delivery & Edge Computing
Content Delivery Network
Intelligent EdgeFabric
CloudPond
Intelligent EdgeCloud
Solutions
SAP Cloud
High Performance Computing
Developer Services
ServiceStage
CodeArts
CodeArts PerfTest
CodeArts Req
CodeArts Pipeline
CodeArts Build
CodeArts Deploy
CodeArts Artifact
CodeArts TestPlan
CodeArts Check
CodeArts Repo
Cloud Application Engine
MacroVerse aPaaS
KooMessage
KooPhone
KooDrive

Overview

Updated on 2025-01-24 GMT+08:00

What Is Near Data Processing?

Near Data Processing (NDP) is a compute pushdown solution to improve data query efficiency. For data-intensive queries, operations such as column extraction, aggregation calculation, and condition filtering are pushed down to multiple nodes on a distributed storage layer for parallel execution. This reduces query processing pressure on compute nodes, improves parallel processing capabilities, and saves network traffic.

How It Works

TaurusDB uses an architecture with decoupled storage and compute to reduce network traffic. Based on this architecture, NDP is used to speed up data queries. Without NDP, all raw data needs to be transmitted from storage nodes to compute nodes for query processing. NDP pushed the most I/O-intensive and CPU-intensive query tasks down to storage nodes. Only the required columns and filtered rows or aggregated results are sent back to compute nodes, greatly reducing network traffic. Additionally, parallel processing across storage nodes reduces the CPU usage of compute nodes and improves the query efficiency.

NDP is integrated with parallel query. Pages are prefetched in batches to realize the entire process in parallel. The query execution efficiency is greatly improved.

Figure 1 How NDP works

Scenarios

NDP is suitable for the following scenarios:

  • Projection

    Column pruning: Only the fields required by a query statement are sent to the compute node.

  • Aggregate

    Typical aggregation operations include COUNT, SUM, AVG, MAX, MIN, and GROUP BY. Only the aggregated results (not all tuples) are sent to the query engine. COUNT (*) is the most common.

  • SELECT - WHERE clause for filtering

    Common condition expressions are COMPARE(>=,<=,<,>,==), BETWEEN, IN, AND/OR, and LIKE.

    A filter expression is executed on the storage nodes. Only the rows that meet the conditions are sent to the compute node.

Application Constraints

  1. InnoDB tables.
  2. Tables with rows in the COMPACT or DYNAMIC format.
  3. Primary keys or B-tree indexes. Hash and full-text indexes are not supported.
  4. SELECT statements among the DML statements. INSERT INTO SELECT statements and SELECT statements that will lock rows (such as SELECT FOR SHARE/UPDATE) are not supported.
  5. Aggregation operations with COUNT, SUM, AVG, MAX, or MIN functions. Those with GROUP BY statements are not supported.
  6. Expressions with numeric, log, time, or partial string types (CHAR and VARCHAR). The utf8mb4 and utf8 character sets are supported.
  7. Expression predicates with comparison operators (<,>,=,<=,>=,!=), IN, NOT IN, LIKE, NOT LIKE, BETWEEN AND, and AND/OR.

Parameters

Table 1 Parameter description

Parameter

Level

Description

ndp_mode

Global, Session

NDP switch. OFF indicates that NDP is disabled. ON indicates that NDP is enabled on both the primary node and read replicas. REPLICA_ON indicates that NDP is only enabled on read replicas.

Values: OFF, ON, and REPLICA_ON

Default value: OFF

ndp_support_features

Global, Session

Features supported by NDP.

  • COUNT: controls whether to push down COUNT aggregation operations to storage nodes for processing through NDP.
  • MIN: controls whether to push down MIN aggregation operations to storage nodes for processing through NDP.
  • MAX: controls whether to push down MAX aggregation operations to storage nodes for processing through NDP.
  • AVG: controls whether to push down AVG aggregation operations to storage nodes for processing through NDP.
  • SUM: controls whether to push down SUM aggregation operations to storage nodes for processing through NDP.
  • GROUP_BY: controls whether to push down GROUP BY aggregation operations to storage nodes for processing through NDP.
  • Partition_Table: controls whether NDP pushdown works for partitioned tables.
  • Instant_Column_Table: controls whether NDP pushdown works for tables with instant column addition enabled.
  • Bloom_filter: controls whether to push down the hash table in a hash join to storage nodes for filtering through NDP.

Values: COUNT, MIN, MAX, AVG, SUM, GROUP_BY, Partition_Table, Instant_Column_Table, and Bloom_filter

Default value: COUNT and SUM

We use cookies to improve our site and your experience. By continuing to browse our site you accept our cookie policy. Find out more

Feedback

Feedback

Feedback

0/500

Selected Content

Submit selected content with the feedback