Overview

The HDC (High-Density Computing) server or cluster is a key component of the Ultipa Powerhouse (v5) architecture, consisting of one or multiple computing nodes optimized for maximum performance and efficiency.

A graphset can be loaded from the physical storage of shard servers into the memory of an HDC server, creating a HDC graph. On these HDC graphs you can execute graph queries and algorithms with enhanced performance. For more information, refer to HDC Graphs.

Showing HDC Servers

Retrieves information about all HDC servers:

show().hdc()

Retrieves information about the HDC server named hdc-server-1:

show().hdc("hdc-server-1")

The information about HDC servers is organized into the following tables:

• _hdc: Shows the basic infomation of HDC servers, including name, addr (IP address and port of the HDC server), status (ACTIVE or DEAD), and last_heartbeat (timestamp of the last heartbeat sent to the meta servers by the HDC server).
• _hdcGraphList: Lists all HDC graphs hosted by each HDC server.

When retrieving a specific HDC server using show().hdc("<hdcServerName>"), two supplementary tables are returned:

• _hdcGraphStats: Lists all HDC graphs created on <hdcServerName> with their statistics.
• _algoList: Lists all algorithms installed on <hdcName>.

Adding an HDC Server

After successfully deploying a new HDC server, it must be registered with the meta servers using the alter().hdc().add() statement before it can be utilized. This process ensures that the new HDC server is recognized within the system.

The following example adds an HDC server with the name hdc-server-2 and the address 127.0.0.1:55555:

alter().hdc().add({name: "hdc-server-2", addr: "127.0.0.1:55555"})

Deleting an HDC Server

You can unregister an inactive or obsolete HDC server from the meta servers using the alter().hdc().delete() statement.

The following example deletes the HDC server with the name hdc-server-2:

alter().hdc().delete({name: "hdc-server-2"})