If you want the space check to occur once per hour in each of n hosts, but at a different time after the hour in each host, issue the following patch. Set one field to the number of minutes after the hour when you want the space check to start, and set another field so that the sum of the two is 90.

To start interval migration twice per hour requires two hosts. Issue the following patches to start space check on the primary host on the hour and start space check on the non-primary host at 30 minutes after the hour:

Primary:      PATCH .MGCB.+60 X'005A'  /* 90 minutes - default  */
 
Non-primary:  PATCH .MGCB.+62 X'001E'  /* 30 minutes after the  */ 
                                       /* hour is the time to   */ 
                                       /* do space check        */
 
              PATCH .MGCB.+60 X'003C'  /* 60 more minutes, to   */
                                       /* take us to the middle */
                                       /* of the next hour      */  

Issue the following patches to set the minimum number of minutes between successive migrations of the same volume to one-half the hourly value:

Primary:   PATCH .MCVT.+422 X'000F'   /* 15 min, SMS      */
           PATCH .MCVT.+496 X'000F'   /* 15 min, non-SMS  */
 
Non-primary:  PATCH .MCVT.+422 X'000F' /* 15 min, SMS     */
              PATCH .MCVT.+496 X'000F' /* 15 min, non-SMS */

If you choose not to use a primary host for interval migration, issue the following patch to substitute a non-primary host by setting its space check time to one minute after the hour:

Non-primary 2:  PATCH .MGCB.+62 X'0001'  /* 1 minute after the  */
                                         /* hour is the time to */
                                         /* do space check      */     

Starting interval migration three times per hour requires three hosts. Issue the following patches to start space check on the primary host on the hour, on the first non-primary host at 20 minutes after the hour, and on the second non-primary host at 40 minutes after the hour:

Primary:      PATCH .MGCB.+60 X'005A'    /* 90 minutes - default  */
 
Non-primary 1:  PATCH .MGCB.+62 X'0014'  /* 20 minutes after the  */
                                         /* hour is the time to   */
                                         /* do space check        */
 
                PATCH .MGCB.+60 X'0046'  /* 70 more minutes, to   */
                                         /* take us to the middle */
                                         /* of the next hour      */
 
 Non-primary 2:  PATCH .MGCB.+62 X'0028' /* 40 minutes after the  */
                                         /* hour is the time to   */
                                         /* do space check        */
 
                PATCH .MGCB.+60 X'0032'  /* 50 more minutes, to   */
                                         /* take us to the middle */
                                         /* of the next hour      */

Issue the following patches to set the minimum number of minutes between successive migrations of the same volume to one-third the hourly value:

Primary:   PATCH .MCVT.+422 X'000A'      /* 10 min, SMS      */
           PATCH .MCVT.+496 X'000A'      /* 10 min, non-SMS  */
 
Non-primary 1:  PATCH .MCVT.+422 X'000A' /* 10 min, SMS      */
                PATCH .MCVT.+496 X'000A' /* 10 min, non-SMS  */
 
Non-primary 2:  PATCH .MCVT.+422 X'000A' /* 10 min, SMS      */
                PATCH .MCVT.+496 X'000A' /* 10 min, non-SMS  */

If you choose not to use a primary host for interval migration, issue the following patch to substitute a non-primary host by setting its space check time to one minute after the hour:

Non-primary 3:  PATCH .MGCB.+62 X'0001'  /* 1 minute after the hour */ 
                                         /* hour is the time to     */  
                                         /* do space check          */