node.js - Why does nodejs have incremental memory usage? -

-

i have gameserver.js file on 100kb's in size. , kept checking task manager after each refresh on browser , kept seeing node.exe memory usage keep rising every refresh. i'm using ws module here: https://github.com/websockets/ws , figured, know what, there memory leak in my code somewhere....

so double check , isolate issue created test.js file , put in default ws code block:

var websocketserver = require('ws').server   , wss = new websocketserver({ port: 9300 });  wss.on('connection', function connection(ws) {   ws.on('message', function incoming(message) {     console.log('received: %s', message);   });  });

and started up:

enter image description here

now, check node.exe's memory usage: enter image description here

the incremental part makes me confused is:

if refresh browser makes connection port 9300 websocket server , @ task manager.. shows:

enter image description here

which at: 14,500 k.

and keeps on rising upon each refresh, theoretically if keep refreshing go through roof. intended? there memory leak in ws module somewhere maybe? whole reason ask because thought maybe in few minutes or when user closes browser go down doesn't.

edit: , core reason why wanted test because figured had memory leak issue in personal code somewhere , wanted check if wasn't me, or vice versa. i'm stumped.

seeing increased memory footprint node.js application normal behaviour. node analyses running code, generates optimised code, reverts unoptimised code (if needed) etc. requires quite lot of memory simple of applications (node.js large part written in javascript follows same optimisations/deoptimisations own code).

additionally, process may granted more memory when needs it, many operating systems remove allocated memory process when decide needed elsewhere (i.e. process). application can, in peaks, consume 1 gb of ram, garbage collection kicks in, usage drops 500 mb process may still keep 1 gb.

detecting presence of memory leaks

to analyse memory usage , memory leaks, must use node's process.memoryusage().

you should set interval dumps memory usage file i.e. every second, apply "stress" on application on several seconds (i.e. web servers, issue several thousand requests). take @ results , see if memory keeps increasing or if follows steady pattern of increasing/decreasing.

detecting source of memory leaks

the best tool node-heapdump. use chrome debugger.

  1. start application , apply initial stress (this generate optimised code , "warm-up" application)
  2. while app idle, generate heapdump
  3. perform single, additional operation (i.e. 1 more request) suspect cause memory leak - trickiest part large apps
  4. generate heapdump
  5. load both heapdumps chrome debugger , compare them - if there memory leak, see there objects allocated during single request not released afterwards
  6. inspect object determine leak occurs

i had opportunity investigate reported memory leak in sails.js framework - can see detailed description of analysis (including pretty graphs etc.) on this issue.

there detailed article working heapdumps strongloop - suggest have @ it.


Comments

Post a Comment

Popular posts from this blog

python - TypeError: start must be a integer -

-
i trying draw 5 turtles, getting typeerror on line 25. here code: import turtle wn = turtle.screen() redrose = turtle.turtle() color = input("what background color be?") fillcolor_f = input("what color of rose be?") redrose.hideturtle() redrose.speed(30) redrose.penup() redrose.left(180) redrose.forward(175) redrose.right(90) redrose.forward(30) redrose.right(90) redrose.pendown() def drawrose(red): redrose.color("pink") redrose.fillcolor(fillcolor_f) redrose.fill(true) in range(red): redrose.forward(i) redrose.right(49) in range(5): drawrose(redrose) redrose.penup() redrose.forward(350) redrose.right(144) redrose.pendown() redrose.fill(false) drawrose(50) wn.bgcolor(color) i trying draw 5 roses, produces errors. doing in interactivepython.org. you recursively calling drawrose wrong parameter. on line 23 ( for in range(red): ) expect red integer...
Read more

c# - DevExpress RepositoryItemComboBox BackColor property ignored -

-
i have following code almost works properly; private void cbstatus_drawitem(object sender, listboxdrawitemeventargs e) { string item = e.item string; if (item != null) { switch (item) { case "1": e.appearance.forecolor = color.green; e.appearance.backcolor = color.green; break; case "2": e.appearance.forecolor = color.orange; e.appearance.backcolor = color.orange; break; case "3": e.appearance.forecolor = color.red; e.appearance.backcolor = color.red; break; } } } when dropdown shown, items forecolor correct, backcolor remains whatever backcolor of theme is; i.e. if i've got set dark theme, backcolor dark, cells in gridview, rather being green/orange/red. i've tried setting e.appearance.options.usebackcolor trying set e....
Read more

django - Creating multiple model instances in DRF3 -

-
1) create multiple model instances 1 api call, asked here: how create multiple model instances django rest framework? tried solution named in link, no success. i trying upload multiple files in 1 api call. result: files uploaded (only once overwrote perform_create) 1 instance created (if send 2 files, latter created instance). my code: class fileuploadserializer(serializers.modelserializer): def __init__(self, *args, **kwargs): many = kwargs.pop('many', true) super(fileuploadserializer, self).__init__(many=many, *args, **kwargs) class meta: model = fileupload read_only_fields = ('created', 'datafile', 'owner') class fileuploadviewset(viewsets.modelviewset): queryset = fileupload.objects.all() serializer_class = fileuploadserializer parser_classes = (multipartparser, formparser, ) def perform_create(self, serializer): file_list = self.request.data.getlist('file') ...
Read more