And also the what is under the “Stack.thread” field stored ? Is it the same for all ?
Maybe you could even share a dump with me ? > On 20 Jul 2016, at 19:22, Norman Maurer <[email protected]> wrote: > > And how many of these you have ? > > Sorry for all the questions :( > >> On 20 Jul 2016, at 19:19, Chris Conroy <[email protected] >> <mailto:[email protected]>> wrote: >> >> Here's an example leaked buf >> >> <Screen Shot 2016-07-20 at 1.18.24 PM.png> >> >> On Wed, Jul 20, 2016 at 1:17 PM, 'Norman Maurer' via Netty discussions >> <[email protected] <mailto:[email protected]>> wrote: >> One last thing… >> >> Can you tell me what the capacity() of the “leaked” buffer is ? >> >>> On 20 Jul 2016, at 19:11, Norman Maurer <[email protected] >>> <mailto:[email protected]>> wrote: >>> >>> Thanks Chris, >>> >>> this sounds really “fishy”. Let me try to debug this a bit more (not sure >>> yet how tho). >>> >>>> On 20 Jul 2016, at 19:06, Chris Conroy <[email protected] >>>> <mailto:[email protected]>> wrote: >>>> >>>> This leak resulted in exhaustion of 4G of NIO memory. The same application >>>> under Netty 3 only ever uses <200MB of NIO memory. I have run several >>>> experiments where I take some traffic, disable the node from serving >>>> traffic, and then force a full GC. The allocated NIO memory does not >>>> return to normal levels. >>>> >>>> Spot checking the byte buf handles from my heap dump, I see lots (all?) >>>> `recycle` and `lastRecycleIds` of `int -2147483648 <tel:2147483648> = >>>> 0x80000000` >>>> >>>> The experiment yesterday with the recycler disabled did not result in any >>>> such leaks over several hours of traffic. >>>> >>>> On Wed, Jul 20, 2016 at 12:41 AM, 'Norman Maurer' via Netty discussions >>>> <[email protected] <mailto:[email protected]>> wrote: >>>> Are you actually sure these are really leaked ? >>>> >>>> The point of the “ThreadLocalUnsafeDirectByteBuf” is that it can be reused >>>> so it is expected that it not gets released after its written but put back >>>> in the recycler. Or you saying there are too many of these ? >>>> >>>> >>>>> On 19 Jul 2016, at 22:39, Chris Conroy <[email protected] >>>>> <mailto:[email protected]>> wrote: >>>>> >>>>> Yes all the leaked buffers look to be ThreadLocalUnsafeDirectByteBuf >>>>> >>>>> Disabling the recycler w/o backpressure on slow readers resulted in >>>>> several massive allocation events. I was able to free them by forcing GC >>>>> so no leaks there. Memory usage with backpressure on slow readers is back >>>>> down to Netty 3 w/o backpressure levels. I don't see any leaks so far. >>>>> >>>>> Assuming that disabling the recycler does indeed prevent leaks, where do >>>>> we go from there? Any ideas of things to look for in my application that >>>>> might cause the recycler to get into a bad state? >>>>> >>>>> On Tue, Jul 19, 2016 at 3:40 PM, 'Norman Maurer' via Netty discussions >>>>> <[email protected] <mailto:[email protected]>> wrote: >>>>> Btw all the “leaking” buffers are always: >>>>> >>>>> ThreadLocalUnsafeDirectByteBuf >>>>> >>>>> ? >>>>> >>>>> >>>>>> On 19 Jul 2016, at 21:29, Chris Conroy <[email protected] >>>>>> <mailto:[email protected]>> wrote: >>>>>> >>>>>> I ran with paranoid while observing the leak and got no messages from >>>>>> the ResourceLeakDetector. >>>>>> >>>>>> Initial results from recycler maxCapacity of 0 are looking positive with >>>>>> respect to the leak. However, I did see a large spike of NIO memory >>>>>> allocated (1G) where the Netty 3 version of this app receiving similar >>>>>> traffic peaks at about 1/10th that. I'll let this run for a while and >>>>>> report back later with the full results. >>>>>> >>>>>> On Tue, Jul 19, 2016 at 2:59 PM, 'Norman Maurer' via Netty discussions >>>>>> <[email protected] <mailto:[email protected]>> wrote: >>>>>> Can you do me a favour and run with: >>>>>> >>>>>> -Dio.netty.recycler.maxCapacity=0 >>>>>> >>>>>> And let me know if you still see some leaks ? >>>>>> >>>>>> >>>>>> >>>>>>> On 19 Jul 2016, at 20:50, Chris Conroy <[email protected] >>>>>>> <mailto:[email protected]>> wrote: >>>>>>> >>>>>>> 4.1.0.Final >>>>>>> >>>>>>> On Tue, Jul 19, 2016 at 2:48 PM, 'Norman Maurer' via Netty discussions >>>>>>> <[email protected] <mailto:[email protected]>> wrote: >>>>>>> Are you using 4.0 or 4.1 ? >>>>>>> >>>>>>>> On 19 Jul 2016, at 20:42, Chris Conroy <[email protected] >>>>>>>> <mailto:[email protected]>> wrote: >>>>>>>> >>>>>>>> I have not been able to reproduce locally yet, but I do see it in a >>>>>>>> cluster that takes a lot of varied traffic. The leak detector has not >>>>>>>> fired for this under advanced. I will give paranoid a shot to be safe, >>>>>>>> but it's my understanding that the leak detection framework is more >>>>>>>> for dealing with pooled byte buf misuse, but in this case I am >>>>>>>> exclusively using unpooled heap byte bufs: these are just the socket >>>>>>>> direct byte bufs that appear to be leaking. >>>>>>>> >>>>>>>> I meant to add this earlier: The path to GC root goes: >>>>>>>> >>>>>>>> io.netty.buffer.ByteBufUtil$ThreadLocalUnsafeDirectByteBuf >>>>>>>> io.netty.util.Recycler$DefaultHandle >>>>>>>> io.netty.util.Recycler$DefaultHandle[] >>>>>>>> io.netty.util.Recycler#Stack >>>>>>>> java.lang.Object[] >>>>>>>> io.netty.util.internal.InternalThreadLocalMap >>>>>>>> ... (more thread local map refs up to java.lang.Thread) >>>>>>>> >>>>>>>> >>>>>>>> >>>>>>>> On Tuesday, July 19, 2016 at 2:17:25 PM UTC-4, Norman Maurer wrote: >>>>>>>> Can you provide a reproducer? Also did you try to run with paranoid >>>>>>>> leak detection >>>>>>>> >>>>>>>> Am 19.07.2016 um 20:04 schrieb Chris Conroy <[email protected] <>>: >>>>>>>> >>>>>>>>> Ah okay: I didn't see the calls to failFlushed since they occur above >>>>>>>>> the stanza I found suspicious. >>>>>>>>> >>>>>>>>> So, the above explanation is probably not correct. Still, I am seeing >>>>>>>>> a leak where DirectByteBufs are rooted to the recycler, and the speed >>>>>>>>> at which these buffers leak appears to be correlated with >>>>>>>>> slow/partial readers. >>>>>>>>> >>>>>>>>> On Monday, July 18, 2016 at 4:36:31 PM UTC-4, Norman Maurer wrote: >>>>>>>>> failFlushed(...) should be called to fail and release all flushed >>>>>>>>> messages. >>>>>>>>> >>>>>>>>> Are you saying this not happens? >>>>>>>>> >>>>>>>>> Am 18.07.2016 um 22:02 schrieb Chris Conroy <[email protected] <>>: >>>>>>>>> >>>>>>>>>> I’ve been trying to track down a NIO memory leak that occurs in a >>>>>>>>>> Netty application I am porting from Netty 3 to Netty 4. This leak >>>>>>>>>> does not occur in the Netty 3 version of the application. >>>>>>>>>> >>>>>>>>>> For now, I’m using only unpooled heap buffers in Netty 4, but NIO >>>>>>>>>> buffers do come into play for socket communication. >>>>>>>>>> >>>>>>>>>> I’ve captured a few heap dumps from affected instances, and in each >>>>>>>>>> it appears that the leaked DirectByteBuf java objects are rooted in >>>>>>>>>> an io.netty.util.Recycler. >>>>>>>>>> >>>>>>>>>> These buffers remain indefinitely: I can disable the application to >>>>>>>>>> drain traffic and force GCs, but the # of NIO buffers and NIO >>>>>>>>>> allocated space stays flat. >>>>>>>>>> >>>>>>>>>> The issue is likely related to slow readers. However, the leak >>>>>>>>>> persists long after all channels have been closed. >>>>>>>>>> >>>>>>>>>> I implemented a writability listener and the leak does appear to go >>>>>>>>>> away if I stop writing to a channel after it goes unwritable. This >>>>>>>>>> is good, but I’m still worried that this just makes the problem less >>>>>>>>>> likely since it’s still possible to write/flush and have pending >>>>>>>>>> data: writability just limits how much data will be buffered. >>>>>>>>>> >>>>>>>>>> Digging into ChannelOutBoundBuffer I see the following stanza in >>>>>>>>>> close: >>>>>>>>>> >>>>>>>>>> >>>>>>>>>> // Release all unflushed messages. >>>>>>>>>> try { >>>>>>>>>> Entry e = unflushedEntry; >>>>>>>>>> while (e != null) { >>>>>>>>>> // Just decrease; do not trigger any events via >>>>>>>>>> decrementPendingOutboundBytes() >>>>>>>>>> int size = e.pendingSize; >>>>>>>>>> TOTAL_PENDING_SIZE_UPDATER.addAndGet(this, -size); >>>>>>>>>> >>>>>>>>>> if (!e.cancelled) { >>>>>>>>>> ReferenceCountUtil.safeRelease(e.msg); >>>>>>>>>> safeFail(e.promise, cause); >>>>>>>>>> } >>>>>>>>>> e = e.recycleAndGetNext(); >>>>>>>>>> } >>>>>>>>>> } finally { >>>>>>>>>> inFail = false; >>>>>>>>>> } >>>>>>>>>> clearNioBuffers(); >>>>>>>>>> This seems a bit curious to me: why are flushed buffers not released >>>>>>>>>> here? Since the leak seems to be rooted in the Recycler, this could >>>>>>>>>> be the culprit…What do you think? >>>>>>>>>> >>>>>>>>>> >>>>>>>>>> -- >>>>>>>>>> You received this message because you are subscribed to the Google >>>>>>>>>> Groups "Netty discussions" group. >>>>>>>>>> To unsubscribe from this group and stop receiving emails from it, >>>>>>>>>> send an email to [email protected] <>. >>>>>>>>>> To view this discussion on the web visit >>>>>>>>>> https://groups.google.com/d/msgid/netty/CA%2B%3DgZKADssKFcs-WCc8%2Br2RWrvbgg3csaJPdcsXL_mCD5yG2bg%40mail.gmail.com >>>>>>>>>> >>>>>>>>>> <https://groups.google.com/d/msgid/netty/CA%2B%3DgZKADssKFcs-WCc8%2Br2RWrvbgg3csaJPdcsXL_mCD5yG2bg%40mail.gmail.com?utm_medium=email&utm_source=footer>. >>>>>>>>>> For more options, visit https://groups.google.com/d/optout >>>>>>>>>> <https://groups.google.com/d/optout>. >>>>>>>>> >>>>>>>>> >>>>>>>>> -- >>>>>>>>> You received this message because you are subscribed to the Google >>>>>>>>> Groups "Netty discussions" group. >>>>>>>>> To unsubscribe from this group and stop receiving emails from it, >>>>>>>>> send an email to [email protected] <>. >>>>>>>>> To view this discussion on the web visit >>>>>>>>> https://groups.google.com/d/msgid/netty/b66894c3-1e65-4235-9201-b4f1dca11a81%40googlegroups.com >>>>>>>>> >>>>>>>>> <https://groups.google.com/d/msgid/netty/b66894c3-1e65-4235-9201-b4f1dca11a81%40googlegroups.com?utm_medium=email&utm_source=footer>. >>>>>>>>> For more options, visit https://groups.google.com/d/optout >>>>>>>>> <https://groups.google.com/d/optout>. >>>>>>>> >>>>>>>> >>>>>>>> -- >>>>>>>> You received this message because you are subscribed to the Google >>>>>>>> Groups "Netty discussions" group. >>>>>>>> To unsubscribe from this group and stop receiving emails from it, send >>>>>>>> an email to [email protected] >>>>>>>> <mailto:[email protected]>. >>>>>>>> To view this discussion on the web visit >>>>>>>> https://groups.google.com/d/msgid/netty/e823494b-caf1-4b1f-b629-405bbdbf4c40%40googlegroups.com >>>>>>>> >>>>>>>> <https://groups.google.com/d/msgid/netty/e823494b-caf1-4b1f-b629-405bbdbf4c40%40googlegroups.com?utm_medium=email&utm_source=footer>. >>>>>>>> For more options, visit https://groups.google.com/d/optout >>>>>>>> <https://groups.google.com/d/optout>. >>>>>>> >>>>>>> >>>>>>> -- >>>>>>> You received this message because you are subscribed to a topic in the >>>>>>> Google Groups "Netty discussions" group. >>>>>>> To unsubscribe from this topic, visit >>>>>>> https://groups.google.com/d/topic/netty/Ve4lnRvFXjM/unsubscribe >>>>>>> <https://groups.google.com/d/topic/netty/Ve4lnRvFXjM/unsubscribe>. >>>>>>> To unsubscribe from this group and all its topics, send an email to >>>>>>> [email protected] >>>>>>> <mailto:[email protected]>. >>>>>>> To view this discussion on the web visit >>>>>>> https://groups.google.com/d/msgid/netty/F788648D-2C4E-4031-BD2A-EFFAEED64BDC%40googlemail.com >>>>>>> >>>>>>> <https://groups.google.com/d/msgid/netty/F788648D-2C4E-4031-BD2A-EFFAEED64BDC%40googlemail.com?utm_medium=email&utm_source=footer>. >>>>>>> >>>>>>> For more options, visit https://groups.google.com/d/optout >>>>>>> <https://groups.google.com/d/optout>. >>>>>>> >>>>>>> >>>>>>> -- >>>>>>> You received this message because you are subscribed to the Google >>>>>>> Groups "Netty discussions" group. >>>>>>> To unsubscribe from this group and stop receiving emails from it, send >>>>>>> an email to [email protected] >>>>>>> <mailto:[email protected]>. >>>>>>> To view this discussion on the web visit >>>>>>> https://groups.google.com/d/msgid/netty/CA%2B%3DgZKAiQseAviHAkbE-eoybDWQsGY1ek6LtXkMCebcMd4WU4g%40mail.gmail.com >>>>>>> >>>>>>> <https://groups.google.com/d/msgid/netty/CA%2B%3DgZKAiQseAviHAkbE-eoybDWQsGY1ek6LtXkMCebcMd4WU4g%40mail.gmail.com?utm_medium=email&utm_source=footer>. >>>>>>> For more options, visit https://groups.google.com/d/optout >>>>>>> <https://groups.google.com/d/optout>. >>>>>> >>>>>> >>>>>> -- >>>>>> You received this message because you are subscribed to a topic in the >>>>>> Google Groups "Netty discussions" group. >>>>>> To unsubscribe from this topic, visit >>>>>> https://groups.google.com/d/topic/netty/Ve4lnRvFXjM/unsubscribe >>>>>> <https://groups.google.com/d/topic/netty/Ve4lnRvFXjM/unsubscribe>. >>>>>> To unsubscribe from this group and all its topics, send an email to >>>>>> [email protected] >>>>>> <mailto:[email protected]>. >>>>>> To view this discussion on the web visit >>>>>> https://groups.google.com/d/msgid/netty/925935D9-92F1-4516-B9E9-524991BF053E%40googlemail.com >>>>>> >>>>>> <https://groups.google.com/d/msgid/netty/925935D9-92F1-4516-B9E9-524991BF053E%40googlemail.com?utm_medium=email&utm_source=footer>. >>>>>> >>>>>> For more options, visit https://groups.google.com/d/optout >>>>>> <https://groups.google.com/d/optout>. >>>>>> >>>>>> >>>>>> -- >>>>>> You received this message because you are subscribed to the Google >>>>>> Groups "Netty discussions" group. >>>>>> To unsubscribe from this group and stop receiving emails from it, send >>>>>> an email to [email protected] >>>>>> <mailto:[email protected]>. >>>>>> To view this discussion on the web visit >>>>>> https://groups.google.com/d/msgid/netty/CA%2B%3DgZKDfjjLkj1yytjhrU564K3Z36SOaqfuPcER-CK3_vrK16g%40mail.gmail.com >>>>>> >>>>>> <https://groups.google.com/d/msgid/netty/CA%2B%3DgZKDfjjLkj1yytjhrU564K3Z36SOaqfuPcER-CK3_vrK16g%40mail.gmail.com?utm_medium=email&utm_source=footer>. >>>>>> For more options, visit https://groups.google.com/d/optout >>>>>> <https://groups.google.com/d/optout>. >>>>> >>>>> >>>>> -- >>>>> You received this message because you are subscribed to a topic in the >>>>> Google Groups "Netty discussions" group. >>>>> To unsubscribe from this topic, visit >>>>> https://groups.google.com/d/topic/netty/Ve4lnRvFXjM/unsubscribe >>>>> <https://groups.google.com/d/topic/netty/Ve4lnRvFXjM/unsubscribe>. >>>>> To unsubscribe from this group and all its topics, send an email to >>>>> [email protected] >>>>> <mailto:[email protected]>. >>>>> To view this discussion on the web visit >>>>> https://groups.google.com/d/msgid/netty/A77C4A03-0A98-4104-9791-7F161A3AAD91%40googlemail.com >>>>> >>>>> <https://groups.google.com/d/msgid/netty/A77C4A03-0A98-4104-9791-7F161A3AAD91%40googlemail.com?utm_medium=email&utm_source=footer>. >>>>> >>>>> For more options, visit https://groups.google.com/d/optout >>>>> <https://groups.google.com/d/optout>. >>>>> >>>>> >>>>> -- >>>>> You received this message because you are subscribed to the Google Groups >>>>> "Netty discussions" group. >>>>> To unsubscribe from this group and stop receiving emails from it, send an >>>>> email to [email protected] >>>>> <mailto:[email protected]>. >>>>> To view this discussion on the web visit >>>>> https://groups.google.com/d/msgid/netty/CA%2B%3DgZKCA8g-4E0AJCf%2BopC2NMufmQBGcWnMXHkwbDj-veW7x8w%40mail.gmail.com >>>>> >>>>> <https://groups.google.com/d/msgid/netty/CA%2B%3DgZKCA8g-4E0AJCf%2BopC2NMufmQBGcWnMXHkwbDj-veW7x8w%40mail.gmail.com?utm_medium=email&utm_source=footer>. >>>>> For more options, visit https://groups.google.com/d/optout >>>>> <https://groups.google.com/d/optout>. >>>> >>>> >>>> -- >>>> You received this message because you are subscribed to a topic in the >>>> Google Groups "Netty discussions" group. >>>> To unsubscribe from this topic, visit >>>> https://groups.google.com/d/topic/netty/Ve4lnRvFXjM/unsubscribe >>>> <https://groups.google.com/d/topic/netty/Ve4lnRvFXjM/unsubscribe>. >>>> To unsubscribe from this group and all its topics, send an email to >>>> [email protected] >>>> <mailto:[email protected]>. >>>> To view this discussion on the web visit >>>> https://groups.google.com/d/msgid/netty/D30BEE2E-9119-4FD3-A144-F6B765B189E8%40googlemail.com >>>> >>>> <https://groups.google.com/d/msgid/netty/D30BEE2E-9119-4FD3-A144-F6B765B189E8%40googlemail.com?utm_medium=email&utm_source=footer>. >>>> >>>> For more options, visit https://groups.google.com/d/optout >>>> <https://groups.google.com/d/optout>. >>>> >>>> >>>> -- >>>> You received this message because you are subscribed to the Google Groups >>>> "Netty discussions" group. >>>> To unsubscribe from this group and stop receiving emails from it, send an >>>> email to [email protected] >>>> <mailto:[email protected]>. >>>> To view this discussion on the web visit >>>> https://groups.google.com/d/msgid/netty/CA%2B%3DgZKADHSVtqFoqMRak34S23OsDrZTEfADSTMpKGa3bguU-ig%40mail.gmail.com >>>> >>>> <https://groups.google.com/d/msgid/netty/CA%2B%3DgZKADHSVtqFoqMRak34S23OsDrZTEfADSTMpKGa3bguU-ig%40mail.gmail.com?utm_medium=email&utm_source=footer>. >>>> For more options, visit https://groups.google.com/d/optout >>>> <https://groups.google.com/d/optout>. >>> >> >> >> -- >> You received this message because you are subscribed to a topic in the >> Google Groups "Netty discussions" group. >> To unsubscribe from this topic, visit >> https://groups.google.com/d/topic/netty/Ve4lnRvFXjM/unsubscribe >> <https://groups.google.com/d/topic/netty/Ve4lnRvFXjM/unsubscribe>. >> To unsubscribe from this group and all its topics, send an email to >> [email protected] >> <mailto:[email protected]>. >> To view this discussion on the web visit >> https://groups.google.com/d/msgid/netty/297B68FF-2B8F-4EE6-92B3-81856A901A7A%40googlemail.com >> >> <https://groups.google.com/d/msgid/netty/297B68FF-2B8F-4EE6-92B3-81856A901A7A%40googlemail.com?utm_medium=email&utm_source=footer>. >> >> For more options, visit https://groups.google.com/d/optout >> <https://groups.google.com/d/optout>. >> >> >> -- >> You received this message because you are subscribed to the Google Groups >> "Netty discussions" group. >> To unsubscribe from this group and stop receiving emails from it, send an >> email to [email protected] >> <mailto:[email protected]>. >> To view this discussion on the web visit >> https://groups.google.com/d/msgid/netty/CA%2B%3DgZKABgsVZaToNgE-UqK04v_fsy508Gwd35BTyq3_rZtfZ5Q%40mail.gmail.com >> >> <https://groups.google.com/d/msgid/netty/CA%2B%3DgZKABgsVZaToNgE-UqK04v_fsy508Gwd35BTyq3_rZtfZ5Q%40mail.gmail.com?utm_medium=email&utm_source=footer>. >> For more options, visit https://groups.google.com/d/optout >> <https://groups.google.com/d/optout>. > -- You received this message because you are subscribed to the Google Groups "Netty discussions" group. To unsubscribe from this group and stop receiving emails from it, send an email to [email protected]. To view this discussion on the web visit https://groups.google.com/d/msgid/netty/E74D1607-BCEE-40B2-AFF3-E38FA28ED3C9%40googlemail.com. For more options, visit https://groups.google.com/d/optout.
