Could you test : https://github.com/netty/netty/pull/5569
? > Am 22.07.2016 um 11:58 schrieb Julien Viet <[email protected]>: > > Yes with branch netty-4.1.3.Final > >> Le 22 Jul 2016 à 09:21, 'Norman Maurer' via Netty discussions >> <[email protected]> a écrit : >> >> Yes this sounds not right… So what are the steps to reproduce ? Fire up a >> vm, checkout vert.x master and run the build ? >> >> >>> On 22 Jul 2016, at 00:51, Julien Viet <[email protected]> wrote: >>> >>> Hi, >>> >>> we are seing OOM "GC overhead limit exceeded" issue in Vert.x test suite >>> on slow machines like Cloudbees or using virtualization on a laptop. >>> >>> This issue means that the VM spend more time in GC than the rest of the VM >>> (98%), but I’m pretty sure everyone here knows that already. >>> >>> In the case of Vert.x testsuite, it happens because we create and destroy >>> many Vertx instances and therefore many event loops / threads during the >>> tests. >>> >>> I spent quite some time on the issue and I found that it happens because >>> the ThreadDeatchWatcher's Recycler DELAYED_RECYCLE fast thread local is a >>> WeakHashMap<Stack, WeakOrderQueue) used by the ThreadPoolCache grows and >>> retains many entries (up to 2000). This WeakHashMap contains recycled >>> objects with large footprint and also the Stack itself reference its Thread >>> that has a large footprint. >>> >>> I am not saying it is a leak per se, but the maps grows and takes time to >>> be garbaged. This does not prevent the testsuite to run on a laptop but it >>> slows it down and on a slow machines it prevents running the testsuite >>> entirely. >>> >>> I believe this behavior was introduced by this commit : >>> https://github.com/netty/netty/commit/afafadd3d7caf1e4b346da049baab0afeae0a4bc >>> >>> The change that makes the whole difference is : >>> https://github.com/netty/netty/commit/afafadd3d7caf1e4b346da049baab0afeae0a4bc#diff-23eafd00fcd66829f8cce343b26c236aR226 >>> >>> The introduction of the field stack in the WeakOrderQueue keeps a reference >>> on the Stack objects, however Stack instances are also weak keys of the >>> fast thread local WeakHashMap and therefore defeats the purpose of the >>> WeakHashMap. Not entirely as it is GC’ed but much less often and increase >>> the memory footprint. >>> >>> let me know what you think >>> >>> Julien >>> >>> -- >>> 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/2A547499-D279-4286-AA95-3447EE2B621E%40julienviet.com. >>> For more options, visit 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/D5C167E1-D3C3-4B8F-B4B8-FD4D1793BC1F%40googlemail.com. >> For more options, visit 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/14FFE4AD-8D8F-4721-8A1E-C763E1F187DE%40julienviet.com. > For more options, visit 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/BC8153A8-4705-438A-BB3F-A5F099FDEAE8%40googlemail.com. For more options, visit https://groups.google.com/d/optout.
