Dump event loop data. Useful to known which processes are running and potentially block your application. Can be used for real time monitoring also.
It basically call core NodeJs functions _getActiveHandles and _getActiveRequests to inspect event loop's state.
No dependency.
Supported and tested : >= 4.x Not supported but should work : 0.12.x
| Version | Supported | Tested |
|---|---|---|
| 9.x | yes | yes |
| 8.x | yes | yes |
| 7.x | yes | yes |
| 6.x | yes | yes |
| 4.x | yes | yes |
| 0.12.x | no | yes( manually) |
| > 0.12.x | no | no |
$ npm install event-loop-inspector --saveconst inspector = require('event-loop-inspector')();
const dump = inspector.dump();
console.log(dump);{
handles:
{
setTimeout:
[{
type: 'setTimeout',
startAfter: 311,
name: 'anonymous',
msecs: 2000
}],
Server:
[{
type: 'Server',
address: '::',
port: 8000,
listeners: [{name: 'connectionListener'}]
}],
Socket:
[{
type: 'Socket',
localAddress: '127.0.0.1',
localPort: 45014,
remoteAddress: '127.0.0.1',
remotePort: 8000,
remoteFamily: 'IPv4',
method: 'GET',
path: '/toto',
headers: {host: '127.0.0.1:8000'},
listeners: []
}]
},
requests:
{
TCPConnectWrap:
[{
type: 'TCPConnectWrap',
address: 'xxx.xxx.xxx.xxx',
port: xxxx,
localAddress: 'xxx.xxx.xxx.xxx',
localPort: xxxx
}]
},
setImmediates:
[
{type: 'setImmediate', name: 'setImmediateTest2'},
{type: 'setImmediate', name: 'anonymous'}
],
nextTicks:
[
{type: 'nextTick', name: 'afterWrite'},
{type: 'nextTick', name: 'anonymous'}
]
}By default setImmediates and process.nextTick can't be retrieved with functions _getActiveHandles/_getActiveRequests. If you want to allow event-loop-inspector to wrap some core functions, instantiate inspector with first argument set as true.
const inspector = require('event-loop-inspector')(true);
const dump = inspector.dump();
console.log(dump);Functions that can be wrapped :
- process.nextTick
- setImmediate
/!\ Enabling this option may lower performance of the functions involved.
$ npm testTo generate coverage :
$ npm run test-coverageCoverage report can be found in coverage/.
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