Dynamic Acceleration

Preparations

Before dynamic acceleration, you need to perform two checks. Applications can be dynamically accelerated only when both conditions are met.

1. Run the following command to check whether the binary file to be optimized can be located again:
   application can be replaced with the binary file to be checked.

   readelf -a application | grep .rela.text

   Figure 1 Example of a readelf command
   

   • If the binary file contains .rela.text, the file can be located again. In this case, the application can be optimized.
   • If the binary file does not contain .rela.text, to allow BOLT to re-arrange functions in your program, you need to add --emit-relocs or -q to the command that was used to create the binary file.
2. Run hce-wae --check /data/apps/mysql-8.0.28/bin/mysqld to check whether the application supports dynamic acceleration.

   If 3 is displayed, dynamic acceleration is supported.

   Figure 2 Example of the check result 3
   

Procedure

In the following operations, the mysqld application in the /data/apps/mysql-8.0.28/bin directory is used as an example.

1. Generate an instrumentation application and run it.
   1. Run the /data/hce-wae/dbo/gen_instrumentation /data/apps/mysql-8.0.28/bin/mysqld command to generate an instrumentation application.

      Command format: /data/hce-wae/dbo/gen_instrumentation Application path

      Figure 3 Example of /data/hce-wae/dbo/gen_instrumentation
      

      The mysqld.inst instrumentation file is generated in the current directory.

      Figure 4 Example of querying an instrumentation file with the .inst suffix
      
   2. Run the instrumentation file to obtain the PID of the application process. In this example, the PID is 87042.
      Figure 5 Example of running an instrumentation file to obtain a PID
      
2. Create a dynamic acceleration configuration file for mysqld.

   Each application to be optimized must have a configuration file. Workload Accelerator dynamically accelerates the application based on the configuration file.

   1. Run the following command to copy the default configuration file /data/hce-wae/config/mysqld.conf:

      [root@localhost]# cp /data/hce-wae/config/hce-wae-tmp.conf /data/hce-wae/config/mysqld.conf 

   2. Set the origin-exe field in the /data/hce-wae/config/mysqld.conf configuration file.
      origin-exe indicates the location of the application to be optimized. In this example, the location is /data/apps/mysql-8.0.28/bin/mysqld.

      [root@localhost]# vim /data/hce-wae/config/mysqld.conf 

      Figure 6 Example of the origin-exe field
      
3. Use the configuration file and the PID to configure dynamic acceleration.

   Command format: hce-wae --conf [PID] [/path/to/config]

   Figure 7 Example of configuring dynamic acceleration
   
4. Enable dynamic acceleration to optimize the instrumentation application.

   Command format: hce-wae --start [PID]

   Figure 8 Enabling dynamic acceleration
   

   You can view the optimization status from the --status parameter. If the status is Running, the process is being optimized. If the status is Finished, the process has been optimized.

   Command format: hce-wae --status [PID]

   Figure 9 Viewing the optimization status
   
5. Use the --snapshot parameter to generate an optimized .dbo binary snapshot file. In this example, the file is mysqld.dbo.
   Figure 10 Example of generating an optimized .dbo binary snapshot file
   

   The default snapshot path is /data/hce-wae/snapshot/. You can change the path in the configuration file as needed. You can use this snapshot file to run the application without repeated optimization.

6. Terminate dynamic acceleration to stop application optimization.

   Command format: hce-wae --stop [PID]

   Figure 11 Example of stopping dynamic acceleration
   

CLI for Dynamic Acceleration

A CLI is provided for dynamic acceleration. Figure 12, Figure 13, and Table 1 show the supported commands.

Figure 12 Startup page of dynamic acceleration

Figure 13 Help page of dynamic acceleration