Ecosyste.ms: Awesome
An open API service indexing awesome lists of open source software.
https://github.com/xin053/hsperfdata
golang parser for java HotSpot virtual meachine performance data V2
https://github.com/xin053/hsperfdata
go hotspot hsperfdata jvm
Last synced: 2 months ago
JSON representation
golang parser for java HotSpot virtual meachine performance data V2
- Host: GitHub
- URL: https://github.com/xin053/hsperfdata
- Owner: xin053
- License: mit
- Created: 2018-06-12T09:08:22.000Z (over 6 years ago)
- Default Branch: master
- Last Pushed: 2023-05-09T17:53:45.000Z (over 1 year ago)
- Last Synced: 2024-06-19T01:48:31.599Z (7 months ago)
- Topics: go, hotspot, hsperfdata, jvm
- Language: Go
- Homepage: https://xin053.github.io/hsperfdata
- Size: 39.1 KB
- Stars: 11
- Watchers: 3
- Forks: 4
- Open Issues: 1
-
Metadata Files:
- Readme: README.md
- License: LICENSE
Awesome Lists containing this project
README
# hsperfdata
[](https://app.fossa.io/projects/git%2Bgithub.com%2Fxin053%2Fhsperfdata?ref=badge_shield)
## What's this?
This is a golang parser for the newest V2 java HotSpot virtual machine performance data, support all platform theoretically.
## What's hsperfdata file?
It is a log directory created by JVM while running your code. By default it is created inside the tmp folder of the operating system that you are using! This directory is a part of Java Performance counter. And the file in this directory is named by the pid number of java process.
For example, if you are running a java process which pid is `1111`, the hsperfdata file is `%TEMP%/hsperfdata_/1111` on `windows`, `/tmp/hsperfdata_/1111` on `linux`.
You can disable creating this directory by using `-XX:-UsePerfData` or `-XX:+PerfDisableSharedMem` which is not recommended.
## Used as a library
**First, you should get the file path string of the hsperfdata file that you want to parser, then use `ReadPerfData` function to parser the hsperfdata file**
There are several functions to get the path, include `PerfDataPath(pid string)`, `PerfDataPaths(pids []string)`, `UserPerfDataPaths(user string)`, `CurrentUserPerfDataPaths()`, `AllPerfDataPaths()`, `DataPathsByProcessName(processName string)`.
For how to use these functions, look at [`hsperfdata function documentation`](https://pkg.go.dev/github.com/xin053/hsperfdata#section-documentation) or you can just read the [`hsperfdata.go`](./hsperfdata.go) to figure out how to use them, the source code is easy to read through.
There is a demo using this project as a go library:
```go
package main
import (
"fmt"
"log"
"sort"
"github.com/xin053/hsperfdata"
)
func main() {
filePaths, err := hsperfdata.DataPathsByProcessName("java")
if err != nil {
log.Fatal(err)
}
for pid := range filePaths {
entryMap, err := hsperfdata.ReadPerfData(filePaths[pid], true)
if err != nil {
log.Fatal("open fail", err)
}
var keys []string
for k := range entryMap {
keys = append(keys, k)
}
sort.Strings(keys)
for _, key := range keys {
fmt.Printf("%s=%v\n", key, entryMap[key])
}
}
}
```
## Used as a command
There is a demo [`hstat.go`](./cmd/hstat.go)
### build hstat yourself
```shell
# go1.12+
go build .\cmd\hstat.go
# Usage: hstat pid
# if you have a java process which pid is 1111, then run this
hstat 1111
```
### use the release package
download the executable from the release page, then here you go!
## Want deeper?
### java HotSpot virtual machine performance data structures
```go
// perfdataHeader http://openjdk.java.net/groups/serviceability/jvmstat/sun/jvmstat/perfdata/monitor/AbstractPerfDataBufferPrologue.html
// source code https://github.com/dmlloyd/openjdk/blob/jdk/jdk/src/jdk.internal.jvmstat/share/classes/sun/jvmstat/perfdata/monitor/AbstractPerfDataBufferPrologue.java
type perfdataHeader struct {
Magic uint32 // magic number - 0xcafec0c0
ByteOrder byte // big_endian == 0, little_endian == 1
Major byte // major version numbers
Minor byte // minor version numbers
// ReservedByte byte // used as Accessible flag at performance data V2
}
// prologue http://openjdk.java.net/groups/serviceability/jvmstat/sun/jvmstat/perfdata/monitor/v2_0/PerfDataBufferPrologue.html
// source code https://github.com/dmlloyd/openjdk/blob/jdk/jdk/src/jdk.internal.jvmstat/share/classes/sun/jvmstat/perfdata/monitor/v2_0/PerfDataBufferPrologue.java
type bufferPrologueV2 struct {
Accessible byte // Accessible flag at performance data V2
Used int32 // number of PerfData memory bytes used
Overflow int32 // number of bytes of overflow
ModTimestamp int64 // time stamp of the last structural modification
EntryOffset int32 // offset of the first PerfDataEntry
NumEntries int32 // number of allocated PerfData entries
}
// entryHeader http://openjdk.java.net/groups/serviceability/jvmstat/sun/jvmstat/perfdata/monitor/v2_0/PerfDataBuffer.html
// source code https://github.com/dmlloyd/openjdk/blob/jdk/jdk/src/jdk.internal.jvmstat/share/classes/sun/jvmstat/perfdata/monitor/v2_0/PerfDataBuffer.java
type entryHeader struct {
EntryLength int32 // entry length in bytes
NameOffset int32 // offset to entry name, relative to start of entry
VectorLength int32 // length of the vector. If 0, then scalar.
DataType byte // JNI field descriptor type
Flags byte // miscellaneous attribute flags 0x01 - supported
DataUnits byte // unit of measure attribute
DataVar byte // variability attribute
DataOffset int32 // offset to data item, relative to start of entry.
}
```
**You can read the source code `hsperfdata.go` to get more information, have a good time!**
**You can open a issue if you have any questions.**
## Attention
The newest java HotSpot virtual machine performance data structures was V2 when I wrote this code, so these data structures may change from release to release, so this parser code only support JVM performance data V2. If there is new version, please open a issue or pull request, thx.
## Reference link
1. http://openjdk.java.net/groups/serviceability/jvmstat/index.html
2. https://github.com/tokuhirom/go-hsperfdata
3. https://github.com/njwhite/telegraf/blob/master/plugins/inputs/hsperfdata/hsperfdata.go
4. https://github.com/twitter/commons/blob/master/src/python/twitter/common/java/perfdata/bin/jammystat.py
5. https://github.com/YaSuenag/hsbeat/blob/master/module/hotspot/hsperfdata/parser.go
## License
[](https://app.fossa.io/projects/git%2Bgithub.com%2Fxin053%2Fhsperfdata?ref=badge_large)