• How to use mysql client connect to ovm manager mysql db?

$ mysql -u root -S /u01/app/oracle/mysql/data/mysqld.sock -p
Enter password: 

• How many ovm manager owned specific database exist?
  There are two ovm manage databse exist in ovs server side:

* appfw (it seems used by weblogic and base framework it depends on)
* ovs   (it is core db ovm manager used)
* performance_schema ( may be performance related)

• What’s the size of ovm manager db(mysql)?

$ mysql -u root -S /u01/app/oracle/mysql/data/mysqld.sock -p
mysql> SELECT table_schema "DB Name", 
              ROUND(SUM(data_length + index_length) / 1024 / 1024, 1) "DB Size in MB" 
       FROM   information_schema.tables 
       GROUP  BY table_schema; 

• What’s the code logic to calculate free available space before backuping ovm manager db?
  • DiskUsage.java

import java.nio.file.*;
import java.nio.file.attribute.*;
import java.io.IOException;
        
public class DiskUsage {

  static final long K = 1024;
       
  static void printFileStore(FileStore store) throws IOException {
      long total = store.getTotalSpace() / K;
      long used = (store.getTotalSpace() - store.getUnallocatedSpace()) / K;
      long unallocated = store.getUnallocatedSpace() / K;
      long avail = store.getUsableSpace() / K;

      String s = store.toString();
      if (s.length() > 20) {
          System.out.println(s);
          s = "";
      }
      System.out.format("%-20s %12d %12d %12d %12dn", s, total, used, avail, unallocated);
 }

 public static void main(String[] args) throws IOException {
     System.out.format("%-20s %12s %12s %12s %12sn", "Filesystem", "kbytes", "used", "avail", "unallocated");
     if (args.length == 0) {
          FileSystem fs = FileSystems.getDefault();
          for (FileStore store: fs.getFileStores()) {
               printFileStore(store);
          }
     } else {
          for (String file: args) {
               FileStore store = Files.getFileStore(Paths.get(file));
               printFileStore(store);
          }
     }
}
}

1. Compile java souce code
   /u01/app/oracle/java/bin/javac DiskUsage.java
   
2. Run java program
   # /u01/app/oracle/java/bin/java DiskUsage /u01/app/oracle/mysql/dbbackup/

• How ovm manager implementation check if there is enough free space before backup mysql db?
  • dbSize: get current mysql db size refer to FAQ0003
  • fsSpace: available free space on ovm manager server refer to FAQ0004
  • if (dbSize * 2) > fsSpace then it think there is enough free space