I got another one: ZOOKEEPER-3163 Use session map to improve the performance when closing session in Netty
So, that doesn't seem too many. We can talk about backporting them, but I don't think they're super critical for the first stable release. Regarding 3.4, I need to validate the embedded scenario, but at least the Java 11 build is green. :) Andor On 1/4/19 18:08, Enrico Olivelli wrote: > Il giorno ven 4 gen 2019 alle ore 17:04 Norbert Kalmar > <nkal...@cloudera.com.invalid> ha scritto: >> +1 for Netty 4 in 3.5 >> >> Pretty much all the pros and cons has been said before me. >> I would only add that this is not a new functionality that we wan't to >> backport. It's a criticall(ish?) bugfix, which requires quite a bit of >> change unfortunately. >> >> Regards, >> Norbert >> >> On Fri, Jan 4, 2019 at 4:36 PM Andor Molnar <an...@apache.org> wrote: >> >>> What are those patches exactly? >>> >>> Comparing the ported version of 3.5 with master I’ve only found 2 patches >>> which are missing: >>> >>> ZOOKEEPER-3146 Limit the maximum client connections per IP in >>> NettyServerCnxnFactory >>> ZOOKEEPER-3177 Refactor request throttle logic in NIO and Netty to keep >>> the same behavior and make the code easier to maintain >>> >>> None of them are critical I would say. >>> Is there anything else I’m missing? > I have compared the histories and I think Andor you are right. > > master: > https://github.com/apache/zookeeper/commits/master > > branch-3.5: > https://github.com/apache/zookeeper/commits/branch-3.5 > > Sorry I was thinking to the amount of patches related to TLS stuff , > but they are not related to Netty 4. > > What about branch 3.4 ? > We don't have reconfig but the case "Start embedded ZK, stop it and > try to restart on the same port" should apply as well. > > Enrico > >>> Andor >>> >>> >>> >>> >>>> On 2019. Jan 4., at 16:27, Enrico Olivelli <eolive...@gmail.com> wrote: >>>> >>>> Il giorno ven 4 gen 2019 alle ore 14:23 Andor Molnar >>>> <an...@apache.org <mailto:an...@apache.org>> ha scritto: >>>>> Hi team / Enrico, >>>>> >>>>> I’d like to get feedback from the community on the following patch >>> (moving the discussion from GitHub to here): >>>>> https://issues.apache.org/jira/browse/ZOOKEEPER-3204 < >>> https://issues.apache.org/jira/browse/ZOOKEEPER-3204> >>>>> https://github.com/apache/zookeeper/pull/753 < >>> https://github.com/apache/zookeeper/pull/753> >>>>> In a nutshell: looks like that Netty 3.10 is broken under Java 11: it >>> doesn’t properly close the underlying socket (probably not closing the >>> registered NIO selectors) and reconfig tests are unable to re-bind the >>> ports. This problem is similar that we already fixed in NIO with the >>> following patch: >>> https://github.com/apache/zookeeper/commit/c3babb94275ad667dc71c10dcb08a383a3c154c2 >>> < >>> https://github.com/apache/zookeeper/commit/c3babb94275ad667dc71c10dcb08a383a3c154c2 >>>>> The problem doesn’t show up on trunk which has been recently upgraded >>> to Netty 4. >>>>> Repro: >>>>> - Start embedded ZK, stop it and try to restart on the same port, or >>>>> - Start normal ensemble and reconfig to use different (client) port. >>> Then reconfig back to the original port which should fail. (that’s the >>> scenario which is covered in ReconfigTest) >>>>> I created the above patch (#753) to backport Netty 4 upgrade to 3.5 and >>> it fixes the problem with Java 11 (it doesn’t cause regression in the >>> pre-commit build either), but Enrico is having concerns about making such >>> big change before the release. >>>>> I tend to agree, but let’s see what are the options. >>>>> >>>>> Thoughts: >>>>> - Do we have to fix this? - Yes. Java 11 is LTS and I the bug is >>> critical. >>>>> - Can we fix Netty 3? - Maybe. Let’s say we find the bug in Netty 3, >>> what can we do? >>>>> a) We cannot workaround from ZooKeeper itself and have to submit >>> a pull request for Netty. I think it’s quite unlikely that they will accept >>> the change given it’s not a security bug, but even if they did, only the >>> upgraded version of Netty 3 would work properly with ZooKeeper. Err. >>>>> b) We can workaround it from ZooKeeper: that could be option #1, >>> but I have a strong feeling about it’s not going to be the case. >>>>> - Shall we upgrade to Netty 4? - this is option #2 >>>>> >>>>> Please share your thoughts, maybe you know about an option #3. >>>> Thank you Andor >>>> >>>> I have thought more about this problem, and I have checked that Netty >>>> 3 is really dead/unmantained (last release in 2016). >>>> If I understand correctly there is no easy workaround (nothing without >>>> hacking Netty 3 internals) >>>> >>>> As soon as we will declare 3.5.5 "stable" the world will hopefully >>>> abandon 3.4 and switch to 3.5 + Netty (because of SSL support). >>>> The network stack is very important so it is better to have Netty 4 as >>>> foundation, I am thinking about security issues, we won't make an >>>> "hotfix" release with the switch to Netty 4 because there is a bad bug >>>> in Netty 3. >>>> So better to switch now. >>>> >>>> But Facebooks friends, expecially @ivmaykov did a lot of bugfixes >>>> around Netty on master branch, we must be sure that what we are >>>> delivering in 3.5.5 is stable. >>>> >>>> We will also have to state clearly in the "release notes" that Netty >>>> version is changed, as this may have a non trivial impact to memory >>>> usage (i.e. Netty 4 uses more Direct memory by default) >>>> >>>> So to recap my final opinion: +1 to switch to Netty 4 if we take care >>>> of port all of the fixes around Netty 4 from master branch and we >>>> state the switch clearly in the release notes >>>> >>>> Enrico >>>> >>>>> Regards, >>>>> Andor >>>
