Is it possible for you to explain a little more detail about these two undocumented functions? is there a reason why they remain undocumented?
process._getActiveHandles() process._getActiveRequests() cheers Tj On Tuesday, June 18, 2013 12:54:04 AM UTC+4, Forrest L Norvell wrote: > > There are a few things you can do, but this is a simple question with a > surprisingly complex answer. The short answer is that knowing the length of > a notional "event loop queue" doesn't really do a very good job of telling > you how *busy* your application is. The different kinds of tasks that > libuv manages (I/O, deferred execution via setTimeout / setInterval, > "asynchronizers" like process.nextTick() and setImmediate(), signal > handlers) are handled at different stages and with different priorities. > > The first thing is to remember that there are a number of different > sources of work feeding into the event queue: > > - there's the process.nextTick() queue, which is processed at a > variety of points through each turn of the event loop > - as Jorge said, there's are tasks set to execute via setImmediate() > - libuv handles the list of I/O requests with available input and > hands those off to turns of the event loop > > See this handy graphic for an only somewhat out-of-date (but *very* useful > -- it should probably be part of the docs) visualization of how all that > happens: > https://a248.e.akamai.net/camo.github.com/e0b4108147b3fa603ef6badd805a2f01d73460fc/687474703a2f2f68746d6c352e6f687473752e6f72672f6e65775f736574496d6d6564696174655f73656d616e746963732e706e67 > > The problem is that turnings of the event loop aren't homogenous, and the > event loop queues on their own don't really tell you the most important > thing, which is whether your application is getting bogged down (for > whatever definition of "bogged down" works well for you). There are modules > like node-toobusy <https://github.com/lloyd/node-toobusy> that try to > monitor the latency of the event loop and tell you if it's taking too long > (which can actually be helpful if you're doing a lot with > process.nextTick(), or are trying to do something CPU-intensive in single > turns of the event loop), but by and large, this kind of information is > hard to gather from inside Node and turns out to be of limited use. > > There's also DTrace, which can give you much finer-grained (or > coarser-grained!) statistics about what's going on with the event loop. > > Most of the time, the only time you'll encounter performance problems tied > to event loop processing is when you're trying to do too much computation > during a single turn of the event loop. I'd generally look pretty much > everywhere else first when trying to do performance tuning. > > F > > > > On Mon, Jun 17, 2013 at 1:21 PM, Jorge <jo...@jorgechamorro.com<javascript:> > > wrote: > >> On 17/06/2013, at 17:20, Chaoran Yang wrote: >> >> > Dear all, >> > >> > Is there any way in node.js I can query the length of event loop queue? >> >> No. >> >> > I assume the event loop has a queue of callbacks. >> >> No there's no queue. An event happens -> its handler (if any) is called: >> it doesn't go through any queue. >> >> > Checking the queue length can be useful to know whether a server is >> busy or not at a certain time. >> >> The only queue there is is the nextTick queue. Well now it's the >> setImmediate queue, I think. But IIRC neither the nextTicked functions' [] >> nor its .length was visible from user code. >> >> -- >> ( Jorge )(); >> >> -- >> -- >> Job Board: http://jobs.nodejs.org/ >> Posting guidelines: >> https://github.com/joyent/node/wiki/Mailing-List-Posting-Guidelines >> You received this message because you are subscribed to the Google >> Groups "nodejs" group. >> To post to this group, send email to nod...@googlegroups.com<javascript:> >> To unsubscribe from this group, send email to >> nodejs+un...@googlegroups.com <javascript:> >> For more options, visit this group at >> http://groups.google.com/group/nodejs?hl=en?hl=en >> >> --- >> You received this message because you are subscribed to the Google Groups >> "nodejs" group. >> To unsubscribe from this group and stop receiving emails from it, send an >> email to nodejs+un...@googlegroups.com <javascript:>. >> For more options, visit https://groups.google.com/groups/opt_out. >> >> >> > -- -- Job Board: http://jobs.nodejs.org/ Posting guidelines: https://github.com/joyent/node/wiki/Mailing-List-Posting-Guidelines You received this message because you are subscribed to the Google Groups "nodejs" group. To post to this group, send email to nodejs@googlegroups.com To unsubscribe from this group, send email to nodejs+unsubscr...@googlegroups.com For more options, visit this group at http://groups.google.com/group/nodejs?hl=en?hl=en --- You received this message because you are subscribed to the Google Groups "nodejs" group. To unsubscribe from this group and stop receiving emails from it, send an email to nodejs+unsubscr...@googlegroups.com. For more options, visit https://groups.google.com/groups/opt_out.
