Example session
This example session illustrates a selection of the commands available and their use.
In the example session, which is generated on a Linux system, some lines have been removed for clarity (and terseness).
User input is prefaced by a greater than symbol (>).
test@madras:~/test> sdk/bin/jdmpview -core core.20121116.154147.16838.0001.dmp
DTFJView version 4.27.57, using DTFJ version 1.10.27022
Loading image from DTFJ...
For a list of commands, type "help"; for how to use "help", type "help help"
Available contexts (* = currently selected context) :
Source : file:///home/test/core.20121116.154147.16838.0001.dmp
*0 : PID: 16867 : JRE 1.8.0 Linux ppc64-64 build 20121115_128521 (pxp6480-20121116_01 )
> help
+ displays the next section of memory in hexdump-like format
- displays the previous section of memory in hexdump-like format
cd changes the current working directory, used for log files
close [context id] closes the connection to a core file
context [ID|asid ID] switch to the selected context
deadlock displays information about deadlocks if there are any
exit Exit the application
find searches memory for a given string
findnext finds the next instance of the last string passed to "find"
findptr searches memory for the given pointer
heapdump generates a PHD or classic format heapdump
help [command name] displays list of commands or help for a specific command
hexdump outputs a section of memory in a hexdump-like format
info <component> Information about the specified component
info class <Java class name> Provides information about the specified Java class
info heap [*|heap name] Displays information about Java heaps
info jitm Displays JIT'ed methods and their addresses
info lock outputs a list of system monitors and locked objects
info mmap Outputs a list of all memory segments in the address space
info mod outputs module information
info proc shortened form of info process
info process displays threads, command line arguments, environment
info sym an alias for 'mod'
info sys shortened form of info system
info system displays information about the system the core dump is from
info thread displays information about Java and native threads
log [name level] display and control instances of java.util.logging.Logger
open [path to core or zip] opens the specified core or zip file
plugins Plugin management commands
list Show the list of loaded plugins for the current context
reload Reload plugins for the current context
showpath Show the DTFJ View plugin search path for the current context
setpath Set the DTFJ View plugin search path for the current context
pwd displays the current working directory
quit Exit the application
set [logging|heapdump] Sets options for the specified command
set heapdump configures heapdump format, filename and multiple heap support
set logging configures several logging-related parameters, starts/stops logging
on turn on logging
off turn off logging
file turn on logging
overwrite controls the overwriting of log files
show [logging|heapdump] Displays the current set options for a command
show heapdump displays heapdump settings
show logging shows the current logging options
whatis [hex address] gives information about what is stored at the given memory address
x/d <hex address> displays the integer at the specified address
x/j <object address> [class name] displays information about a particular object or all objects of a class
x/k <hex address> displays the specified memory section as if it were a stack frame parameters
x/x <hex address> displays the hex value of the bytes at the specified address
> set logging file log.txt
logging turned on; outputting to "/home/test/log.txt"
> info system
Machine OS: Linux
Hypervisor: PowerVM
Machine name: madras
Machine IP address(es):
9.20.88.155
System memory: 8269201408
Dump creation time: 2015/08/10 14:44:36:019
Dump creation time (nanoseconds): 21314421467539
Java version:
JRE 1.8.0 Linux ppc64-64 build 20121115_128521 (pxp6490-20121116_01)
JVM start time: 2015/08/10 14:44:05:690
JVM start time (nanoseconds): 21284086192267
> info thread *
native threads for address space
process id: 16838
thread id: 16839
registers:
native stack sections:
native stack frames:
properties:
associated Java thread:
name: main
Thread object: java/lang/Thread @ 0x2ffd1e08
Priority: 5
Thread.State: RUNNABLE
JVMTI state: ALIVE RUNNABLE
Java stack frames:
bp: 0x0000000000085b28 method: void com/ibm/jvm/Dump.SystemDumpImpl() (Native Method)
objects: <no objects in this frame>
bp: 0x0000000000085b40 method: void com/ibm/jvm/Dump.SystemDump() source: Dump.java:41
objects: <no objects in this frame>
bp: 0x0000000000085b68 method: void mySystemDump.main(String[]) source: mySystemDump.java:29
objects: <no objects in this frame>
===Lines Removed===
name: GC Worker
id: 16860
Thread object: java/lang/Thread @ 0x3001b980
Priority: 5
Thread.State: WAITING
JVMTI state: ALIVE WAITING WAITING_INDEFINITELY IN_OBJECT_WAIT
waiting to be notified on: "MM_ParallelDispatcher::workerThread" with ID 0x1004cbc8 owner name: <unowned>
Java stack frames: <no frames to print>
name: GC Worker
id: 16861
Thread object: java/lang/Thread @ 0x3001c180
Priority: 5
Thread.State: WAITING
JVMTI state: ALIVE WAITING WAITING_INDEFINITELY IN_OBJECT_WAIT
waiting to be notified on: "MM_ParallelDispatcher::workerThread" with ID 0x1004cbc8 owner name: <unowned>
Java stack frames: <no frames to print>
name: Signal Dispatcher
id: 16847
Thread object: com/ibm/misc/SignalDispatcher @ 0x3000f268
Priority: 5
Thread.State: RUNNABLE
JVMTI state: ALIVE RUNNABLE
Java stack frames:
bp: 0x00000000000df748 method: int com/ibm/misc/SignalDispatcher.waitForSignal() (Native Method)
objects: <no objects in this frame>
bp: 0x00000000000df788 method: void com/ibm/misc/SignalDispatcher.run() source: SignalDispatcher.java:54
objects: 0x30015828 0x30015828
===Lines Removed===
> info heap *
Heap #1: Generational@fff78303d30
Section #1: Heap extent at 0x100d0000 (0x300000 bytes)
Size: 3145728 bytes
Shared: false
Executable: false
Read Only: false
Section #2: Heap extent at 0x2ffd0000 (0x80000 bytes)
Size: 524288 bytes
Shared: false
Executable: false
Read Only: false
Section #3: Heap extent at 0x30050000 (0x80000 bytes)
Size: 524288 bytes
Shared: false
Executable: false
Read Only: false
> info class java/lang/String
name = java/lang/String
ID = 0x37c00 superID = 0x30300
classLoader = 0x2ffe9b58 modifiers: public final
number of instances: 2146
total size of instances: 51504 bytes
Inheritance chain....
java/lang/Object
java/lang/String
Fields......
static fields for "java/lang/String"
private static final long serialVersionUID = -6849794470754667710 (0xa0f0a4387a3bb342)
public static final java.util.Comparator CASE_INSENSITIVE_ORDER = <object> @ 0x2ffd0278
private static final char[] ascii = <object> @ 0x2ffd02c8
private static String[] stringArray = <object> @ 0x2ffd0298
private static final int stringArraySize = 10 (0xa)
static boolean enableCopy = false
private static int seed = -126504465 (0xfffffffff875b1ef)
private static char[] startCombiningAbove = <object> @ 0x100d0c40
private static char[] endCombiningAbove = <object> @ 0x100d0cc0
private static final char[] upperValues = <object> @ 0x100d0d40
private static final java.io.ObjectStreamField[] serialPersistentFields = <object> @ 0x2ffd0920
non-static fields for "java/lang/String"
private final char[] value
private final int offset
private final int count
private int hashCode
private int hashCode32
Methods......
Bytecode range(s): : private static native int getSeed()
Bytecode range(s): fff76d8ce48 -- fff76d8ce5e: public void <init>()
Bytecode range(s): fff76d8ce88 -- fff76d8cecd: private void <init>(String, char)
Bytecode range(s): fff76d8cf10 -- fff76d8cf19: public void <init>(byte[])
Bytecode range(s): fff76d8cf40 -- fff76d8cf4a: public void <init>(byte[], int)
Bytecode range(s): fff76d8cf7c -- fff76d8cfb5: public void <init>(byte[], int, int)
Bytecode range(s): fff76d8cff8 -- fff76d8d065: public void <init>(byte[], int, int, int)
Bytecode range(s): fff76d8d0c4 -- fff76d8d10c: public void <init>(byte[], int, int, String)
===Lines Removed===
> whatis 0x2ffd0298
heap #1 - name: Generational@fff78303d30
0x2ffd0298 is within heap segment: 2ffd0000 -- 30050000
0x2ffd0298 is the start of an object of type [Ljava/lang/String;