Question & Answer
Question
How to read HP Verbose GC Log? what are the different columns?
Answer
-Xverbosegc sends log information to stderr by default.
The
following command line sends -Xverbosegc output to a text file named
yourApp_pid<pid>.vgc:
java
-Xverbosegc:file=yourApp_pid<pid>.vgc yourApp
At every garbage collection 20 fields are printed as follows:
GC: %1 %2 %3 %4 %5 %6 %7 %8 %9 %10 %11 %12 %13 %14 %15 %16 %17 %18
%19 %20
The following table
contains brief descriptions of these 20 fields:
Field
| Information in Field |
1 | Type
of GC:
|
2 |
Additional information based on GC type in field 1.
|
3</
div> | Program time at the
beginning of the GC, in seconds. |
4 |
GC invocation. Counts of background CMS GCs and
other GCs are maintained separately. |
5 |
Size of the object allocation request that
forced the GC, in bytes. |
6 |
Tenuring threshold—determines how long the newborn object
remains in the New Generation. |
7 |
Eden Sub-space (within the New Generation) occupied before
GC. |
8 | Eden
Sub-space (within the New Generation) occupied after GC. |
9 </
td> | Eden Sub-space (within the New Generation)
current capacity. |
10 |
Survivor Sub-space (within the New Generation) occupied before
GC. |
11 |
Survivor Sub-space (within the New Generation) occupied after
GC. |
12 |
Survivor Sub-space (within the New Generation) current
capacity. |
13 | Old
Generation occupied before GC. |
14 |
Old Generation occupied after GC. |
15 </
td> | Old Generation current capacity.
|
16</
div> | Permanent Generation
(storage of Reflective Objects) occupied before GC. |
17 </
td> | Permanent Generation (storage of Reflective
Objects) occupied after GC. |
18 |
Permanent Generation (storage of Reflective Objects) current
capacity. |
19 | The
total stop-the-world duration, in seconds. |
20 |
The total time used in collection, in
seconds. |
Example:
<GC: <u>2 1</u>
174206.339748 79</div> <div> </div> <div> </div> <div>In the above gc log,
first one shows it is a full gc; second one shows it is perm gc.</div> <p>
[{"Product":{"code":"SS6PEW","label":"IBM Sterling Order Management"},"Business Unit":{"code":"BU048","label":"IBM Software"},"Component":"Not Applicable","Platform":[{"code":"PF025","label":"Platform Independent"}],"Version":"All","Edition":"","Line of Business":{"code":"LOB59","label":"Sustainability Software"}}]
Historical Number
HTG2328
Was this topic helpful?
Document Information
Modified date:
16 June 2018
UID
swg21562190