dhistory
Performs actions upon ReplayEngine
Format
dhistory [ -info ] [ -get_time ] [ -go_time time ] [ -go_live ]
[-enable ] [ -disable ] [-save file]
Arguments
-info
Writes ReplayEngine information including the current time, the live time, and whether the process is in replay or record mode. If you do not enter any arguments, -info is the default.
-get_time
Displays the current time. The output of this command shows an integer value followed by an address. The first integer value is a virtual timestamp. This virtual timestamp does not refer to the exact point in time; it has a granularity that is typically a few lines of code. The address value is a PC value that corresponds to a precise point within that block of code.
-go_time time
Places the process back to the virtual time specified by the
time integer argument. The
time argument is a virtual timestamp as reported by
dhistory -get_time. You cannot use this command to move to a specific instruction but you can use it to get to within a small block of code (usually within a few lines of your intended point in execution history). This command is typically used either for roughly bookmarking a point in code or for searching execution history. It may need to be combined with stepping and
duntil commands to return to an exact position.
-go_live
Places the process back to the PC and back into record mode. You can resume your “regular” debugging session.
-enable
Enables ReplayEngine, starting the history
-disable
Disables ReplayEngine, ending the history.
-save file
Saves the current replay history to a file. There is an optional argument to specify the name of the file to save to. The file specification can be a path or a simple file name, in which case it is saved in the current working directory. If no file is specified, the recording is saved in the current working directory with the file name replay_pid_hostname.recording.
To reload the recording file, use one of the following commands based on the functionality for loading core files. TotalView recognizes the recording file for what it is and acts appropriately.
To reload a recording at startup:
totalview executable recording-file
To reload a recording file when TotalView is running:
dattach filename -c recording-file
The recording-file argument can be either a path or a simple file name, in which case the current working directory is assumed.
Description
The dhistory command displays information about the current process either by default or when using the -info argument. In addition, options to this command can obtain a debugging time, which can be stored in a variable to go back to a particular time.
In addition, you can enable and display ReplayEngine as well as put it back into regular debugging mode using the -go_live option. You’ll need to do this after your program is placed into replay mode. This occurs whenever you use any GUI or CLI command that moves to replay mode. For example, in the CLI, this can occur when you execute such commands as dnext or dout.
Command alias
Alias | Definition | Description |
replay | dhistory | Performs actions upon ReplayEngine. |
Examples
dhistory
Typing this command displays the following information:
History info for process 1
Live time: | 421 0x80485d6 |
Current time: | 421 0x80485d6 |
Live PC: | 0x80485d6 |
Record Mode: | True |
Replay Wanted: | True |
Stop Reason: | Normal result [waitpid, search, or goto_time] |
Temp directory: | /tmp/replay_jsm_local/replay_session_pZikY9 |
Event log mode: | circular |
Event log size: | 268435456 |