Since someone mentioned ABI, keep in mind that API compatibility does not necessarily mean ABI compatibility. libpython, for example, may, within a major version, guarantee backwards API compatibility (you can still compile successfully), but does not guarantee ABI compatibility, as structure sizes may change, for example.
On Sun, Mar 11, 2018 at 1:56 PM kellen sunderland < kellen.sunderl...@gmail.com> wrote: > "Did ML lib increase their major version after deprecating RDD?" > > Answering my own question. They will increase major version after RDD is > removed. This is basically scenario 1 from above. It would mean we > release MXNet 2.0 with the Scala changes. > > On Sun, Mar 11, 2018 at 9:54 PM, kellen sunderland < > kellen.sunderl...@gmail.com> wrote: > > > "Why refactoring and deprecating means separating version from mxnet > > core? Apache Spark MLLib refactors and deprecates a lot (e.g., they > > deprecates RDD API), our C API also deprecates things, remember there > are a > > bunch of xxxEx in c_api.h?" > > > > Did ML lib increase their major version after deprecating RDD? > > > > "They will. Scala API runs auto code-generation to extract Symbol method > > from MXNet core. For example, users can write and compile > > Symbol.NewOperator with one Scala API version, but they cannot run it > with > > an mxnet-core .so which does not have NewOperator / or have NewOperator > > with different args." > > > > Not sure I fully understand the scenario you're describing here. Is this > > the case where a user writes a new operator against one version of > > libmxnet.so and then runs it on an older version? In this case they'd > need > > to set a dependency on the current libmxnet.so ABI that they're running > > against, and ensure that their jar was using that version or newer. This > > is the goal of SemVer per interface. > > > > "By doing major version change to Scala API, we remind users 'hey, be > > careful, we have something incompatible!' But then what?" > > They either choose to update their package and then fix potential > breaking > > API changes (the likely case), or they stick with the current version. > > > > "Users get more confused with the version mapping. And it introduces > > overhead to maintain." > > I'm not sure why users even need to know about the version mapping. If > > I'm only interested in the Scala package from maven, why do I care which > > version of libmxnet.so I'm using? > > > > > > > > On Sun, Mar 11, 2018 at 8:06 PM, YiZhi Liu <eazhi....@gmail.com> wrote: > > > >> > > >> > Changing namespaces is one example of a required major version change, > >> but > >> > there are more reasons like general refactoring or some deprecated > APIs > >> > just being hard to maintain. > >> > >> Why refactoring and deprecating means separating version from mxnet > core? > >> Apache Spark MLLib refactors and deprecates a lot (e.g., they deprecates > >> RDD API), our C API also deprecates things, remember there are a bunch > of > >> xxxEx in c_api.h? > >> > >> They won't get a strange error, assuming we're talking about Scala users > >> > who are upgrading from a package with the same namespace they will > rely > >> on > >> > the package manager to give them an update which should be painless. > >> > >> They will. Scala API runs auto code-generation to extract Symbol method > >> from MXNet core. For example, users can write and compile > >> Symbol.NewOperator with one Scala API version, but they cannot run it > with > >> an mxnet-core .so which does not have NewOperator / or have NewOperator > >> with different args. > >> > >> By doing major version change to Scala API, we remind users 'hey, be > >> careful, we have something incompatible!' But then what? Users get more > >> confused with the version mapping. And it introduces overhead to > maintain. > >> > >> @Chris, I think we can have two separate votes. > >> > >> > >> 2018-03-11 9:19 GMT-07:00 Chris Olivier <cjolivie...@gmail.com>: > >> > >> > Ok, so why don’t we have two votes? > >> > > >> > 1) change namespace is a separate vote since it’s a code change and > has > >> > different voting rules (can be vetoed) > >> > > >> > 2) whether to disconnect non-C-API versioning from C-API versioning > and > >> > have parallel versioning of all non-C APIs (process rule, so > majority, I > >> > think is the rule, right?) > >> > > >> > -Chris > >> > > >> > On Sun, Mar 11, 2018 at 8:46 AM kellen sunderland < > >> > kellen.sunderl...@gmail.com> wrote: > >> > > >> > > Sorry, the namespace should have been 'org.apache.mxnet' with the > >> > artifact > >> > > as 'mxnet-incubating'. > >> > > > >> > > On Sun, Mar 11, 2018 at 4:44 PM, kellen sunderland < > >> > > kellen.sunderl...@gmail.com> wrote: > >> > > > >> > > > YiZhi, In general I agree that your points and examples are the > >> ideal > >> > > > case, but in the MXNet situation there are some trade-offs we have > >> to > >> > > > make. Let me try to specifically answer your points: > >> > > > > >> > > > "Do you mean we have different version for 'ml.dmlc' namespace and > >> > > > 'org.apache' namespace?" > >> > > > No I am not trying to saying that. I believe Marco, Naveen and I > are > >> > all > >> > > > proposing we use a single org.apache.incubating.mxnet namespace > >> moving > >> > > > forward, which would require a major version change to our product > >> API > >> > > > under our current versioning scheme. Marco and I are proposing we > >> > apply > >> > > > this MV change _only_ to the scala package's API. > >> > > > > >> > > > "How to tell which Scala API version works with which MXNet core > >> > version? > >> > > > By document?" > >> > > > Yes users will be able to tell via the website, release docs, > maven > >> > > > package information, pom file, etc. > >> > > > > >> > > > "How many users will read the whole document and carefully pair > the > >> > > > version id before they run into a strange error and give up?" > >> > > > They won't get a strange error, assuming we're talking about Scala > >> > users > >> > > > who are upgrading from a package with the same namespace they will > >> rely > >> > > on > >> > > > the package manager to give them an update which should be > painless. > >> > > > > >> > > > Secondly software developers understand that packages, not > products, > >> > have > >> > > > versions. They know that these versions are used to communicate > >> when > >> > > APIs > >> > > > are broken. There's examples of Apache packages doing this for > >> > packages > >> > > > that include multiple interfaces, for example first-party modules > >> > > packaged > >> > > > with the HTTP server, or log4j's language bindings (arguably quite > >> > > similar > >> > > > to what Naveen is doing). > >> > > > > >> > > > While we can debate the right way to version packages, I think > >> there's > >> > a > >> > > > clear community decision here to get Naveen unblocked: > >> > > > > >> > > > (1) We continue semantically versioning across all APIs, meaning > >> that > >> > > this > >> > > > change would get released with MXNet 2.*. > >> > > > (2) You version package interfaces semantically and have a > >> compatible > >> > > > version mapping. > >> > > > (3) Status quo, we continue to release a Scala package as-is, > >> breaking > >> > > > apache guidelines for artifact generation. > >> > > > (4) We rely on the namespace change itself to communicate a change > >> in > >> > the > >> > > > interface. We don't consider this a major change. > >> > > > > >> > > > My (non-binding) preference would be for option 2. > >> > > > > >> > > > -Kellen > >> > > > > >> > > > On Sun, Mar 11, 2018 at 12:44 PM, Marco de Abreu < > >> > > > marco.g.ab...@googlemail.com> wrote: > >> > > > > >> > > >> Changing namespaces is one example of a required major version > >> change, > >> > > but > >> > > >> there are more reasons like general refactoring or some > deprecated > >> > APIs > >> > > >> just being hard to maintain. Things like these happen quite > >> frequently > >> > > and > >> > > >> it's a problem every software project has to face and find a > >> solution > >> > > for. > >> > > >> > >> > > >> Regarding ' How to tell which Scala API version works with which > >> MXNet > >> > > >> core > >> > > >> version?': We could just bundle MXNet with the released API > >> package as > >> > > we > >> > > >> do right now, but we would give each interface it's own version > and > >> > > >> publish > >> > > >> them on their distribution platforms accordingly. Just an > example: > >> > > >> >Scala-Package -> MXNet-Version > >> > > >> >> 1.0 -> 1.0 > >> > > >> >> 1.1 -> 1.1 > >> > > >> >> 2.0 -> 1.2 > >> > > >> >> 2.1 -> 1.3 > >> > > >> >> 3.0 -> 2.0 > >> > > >> > >> > > >> > R-Package -> MXNet-Version > >> > > >> >> 1.0 -> 1.0 > >> > > >> >> 2.0 -> 1.1 > >> > > >> >> 2.1 -> 1.2 > >> > > >> >> 2.2 -> 1.3 > >> > > >> >> 3.0 -> 2.0 > >> > > >> > >> > > >> This is always an N-to-1 mapping, while N being the versions of > our > >> > APIs > >> > > >> and 1 the MXNet Core version. From MXNets versioning perspective, > >> this > >> > > >> would then looking the following: > >> > > >> > MXNet-Version -> APIs > >> > > >> >> 1.0 -> Scala_1.0; R_1.0 > >> > > >> >> 1.1 -> Scala_1.1; R_2.0 > >> > > >> >> 1.2 -> Scala_2.0; R_2.1 > >> > > >> >> 1.3 -> Scala_2.1; R_2.2 > >> > > >> >> 2.0 -> Scala_3.0; R_3.0 > >> > > >> > >> > > >> This would give us the liberty to develop MXNet without > >> restricting us > >> > > too > >> > > >> much - of course, major version increments will still have to be > >> > > >> considered > >> > > >> carefully. I don't think that this would harm transparency too > much > >> > and > >> > > >> there's no need to write big documentation. > >> > > >> > >> > > >> -Marco > >> > > >> > >> > > >> > >> > > >> On Sun, Mar 11, 2018 at 12:16 PM, YiZhi Liu <liuyi...@apache.org > > > >> > > wrote: > >> > > >> > >> > > >> > I have no idea how separating Scala API version can solve the > >> > > >> > 'compatibility' problem. Do you mean we have different version > >> for > >> > > >> > 'ml.dmlc' namespace and 'org.apache' namespace? Do these two > >> > versions > >> > > >> > have same behavior? How to tell which Scala API version works > >> with > >> > > >> > which MXNet core version? By document? How many users will read > >> the > >> > > >> > whole document and carefully pair the version id before they > run > >> > into > >> > > >> > a strange error and give up? > >> > > >> > > >> > > >> > Moreover, changing namespace is an issue that is really rare > and > >> > > >> > hardly happens. For other 'compatibility' problem, for example, > >> the > >> > > >> > class/function definitions, should handle the compatibility > >> itself. > >> > > >> > You'll never expect a project to have a different version for > >> > changing > >> > > >> > 'calculate(int)' to 'calculate(float)', it should just add a > new > >> > > >> > function 'calculate(float)'. > >> > > >> > > >> > > >> > Regarding 'In this case the Scala interface is clearly a > separate > >> > > >> > entity from the C API.'. Everything can be seen as a separate > >> > entity, > >> > > >> > the mxnet engine, the graph description, operators, python API, > >> > gluon > >> > > >> > API, etc. We should think carefully what we want to provide, > and > >> > what > >> > > >> > our users need. > >> > > >> > > >> > > >> > As an example, Apache Spark, still has SparkR (R API), PySpark > >> > (Python > >> > > >> > API), MLLib, GraphX ... as part of its release, and have the > same > >> > > >> > version as Spark core as well as its Scala/Java API. > >> > > >> > > >> > > >> > 2018-03-10 23:58 GMT-08:00 kellen sunderland < > >> > > >> kellen.sunderl...@gmail.com > >> > > >> > >: > >> > > >> > > +1 (non-binding) to what Marco is describing. +1 > >> (non-binding) to > >> > > >> > getting the Scala bindings with the namespace change into > Maven. > >> > > >> > > > >> > > >> > > The general best practice for SemVer, which is used by most > >> > projects > >> > > >> > that employ SemVer, is to apply SemVer to the public APIs of > >> > packages > >> > > >> that > >> > > >> > ship with your project. If you have several independent APIs > >> this > >> > > could > >> > > >> > mean that they are versioned separately from each other, and > from > >> > the > >> > > >> > overall project versioning mechanism. > >> > > >> > > > >> > > >> > > For example, the .NET Core library ships with a number of > >> > binaries, > >> > > >> each > >> > > >> > with their own SemVerioned APIs. They also have a high-level, > >> easy > >> > to > >> > > >> > understand version for the package as a whole: > >> > > >> > https://docs.microsoft.com/en-us/dotnet/core/versions/. > >> > > >> > > > >> > > >> > > Nodesource has a good description of this: > >> > > >> http://nodesource.com/blog/ > >> > > >> > semver-a-primer/ > >> > > >> > > “Semver is a scheme for interface versioning for the benefit > of > >> > > >> > interface consumers, thus if a tool has multiple interfaces, > >> e.g. an > >> > > API > >> > > >> > and a CLI, these interfaces may evolve independent versioning.” > >> > > >> > > > >> > > >> > > SemVer at its core is a communication mechanism to inform > >> > developers > >> > > >> of > >> > > >> > incompatibilities. In this case the Scala interface is clearly > a > >> > > >> separate > >> > > >> > entity from the C API. I.e. changing the Scala namespace isn’t > >> > going > >> > > to > >> > > >> > break C API users. It does not communicate anything useful to > >> these > >> > > >> users > >> > > >> > if we up their major version in response to a Scala change, it > >> > simply > >> > > >> > breaks compatibility. If we group all interfaces together, and > >> > > >> increment > >> > > >> > whenever any of them has a breaking change we’ll soon be at > MXNet > >> > > >> version > >> > > >> > 587. We’ll be forcing our users to check compatibility and > >> update > >> > > their > >> > > >> > dependency tracking constantly. The end result is that our > users > >> > will > >> > > >> stop > >> > > >> > pulling in new versions of the library. > >> > > >> > > > >> > > >> > > What I would propose is that (1) we have a high-level SemVer > >> > system > >> > > >> that > >> > > >> > tracks our C_API. This is the ‘MXNet’ version that we > generally > >> > refer > >> > > >> to > >> > > >> > and emphasize for our public releases. For each API we have an > >> > > >> independent > >> > > >> > versioning system that if we can, we fix to the MXNet version. > >> When > >> > > it > >> > > >> > makes sense we version these APIs independently. So for > example > >> we > >> > > >> could > >> > > >> > have a MXNet 1.2 release that ships with a 2.0 Scala API / R > API. > >> > > >> > > > >> > > >> > > In terms of Apache process I think shipping artifacts with a > >> > > >> non-Apache > >> > > >> > namespace is a bigger issue than whatever versioning > conventions > >> we > >> > > >> decide > >> > > >> > to use. > >> > > >> > > > >> > > >> > > -Kellen > >> > > >> > > > >> > > >> > > From: Carin Meier > >> > > >> > > Sent: Saturday, March 10, 2018 1:41 PM > >> > > >> > > To: dev@mxnet.incubator.apache.org > >> > > >> > > Cc: d...@mxnet.apache.org > >> > > >> > > Subject: Re: Publishing Scala Package/namespace change > >> > > >> > > > >> > > >> > > +1 as well. I'm actively developing a Clojure package for > MXNet > >> > that > >> > > >> uses > >> > > >> > > the jars from the Scala package. > >> > > >> > > > >> > > >> > > - Carin > >> > > >> > > > >> > > >> > > On Fri, Mar 9, 2018 at 4:44 PM, YiZhi Liu < > eazhi....@gmail.com > >> > > >> > > >> wrote: > >> > > >> > > > >> > > >> > >> +1 for changing the namespace asap. for the maven deploy, we > >> can > >> > > have > >> > > >> > >> it build along with pip deployment. > >> > > >> > >> > >> > > >> > >> > >> > > >> > >> 2018-03-09 10:15 GMT-08:00 Naveen Swamy <mnnav...@gmail.com > >: > >> > > >> > >> > Hi Guys, > >> > > >> > >> > > >> > > >> > >> > I am working on MXNet Scala Inference APIs > >> > > >> > >> > <https://issues.apache.org/jira/browse/MXNET-50> along > with > >> > > >> another > >> > > >> > >> > contributor Roshani. A while back I noticed that we > haven't > >> > been > >> > > >> > >> publishing > >> > > >> > >> > the scala package to Maven for a while now(last one being > >> > > v0.11.1a > >> > > >> > under > >> > > >> > >> > the dmlc namespace). > >> > > >> > >> > Currently users have to build the package manually and > then > >> use > >> > > it, > >> > > >> > this > >> > > >> > >> > hinders adoption and also is painful to build everything > >> from > >> > > >> source. > >> > > >> > >> > > >> > > >> > >> > I also see that we haven't changed the namespace to > >> org.apache > >> > > and > >> > > >> > >> instead > >> > > >> > >> > are still ml.dmlc namespace. > >> > > >> > >> > > >> > > >> > >> > I wanted to seek your opinion about changing the > MXNet-Scala > >> > > >> package > >> > > >> > >> > namespace to org.apache for the Scala package and publish > to > >> > > Maven > >> > > >> in > >> > > >> > the > >> > > >> > >> > upcoming release. I understand that this probably breaks > the > >> > > Semver > >> > > >> > >> > semantics that is agreed upon, However I would like to > point > >> > out > >> > > >> that > >> > > >> > the > >> > > >> > >> > Scala package has never been published to maven as 1.0 > under > >> > > >> > org.apache. > >> > > >> > >> > > >> > > >> > >> > Open to suggestions. > >> > > >> > >> > > >> > > >> > >> > Thanks, Naveen > >> > > >> > >> > >> > > >> > >> > >> > > >> > >> > >> > > >> > >> -- > >> > > >> > >> Yizhi Liu > >> > > >> > >> DMLC member > >> > > >> > >> Amazon Web Services > >> > > >> > >> Vancouver, Canada > >> > > >> > >> > >> > > >> > > > >> > > >> > > >> > > >> > > >> > > >> > > >> > > >> > -- > >> > > >> > Yizhi Liu > >> > > >> > DMLC member > >> > > >> > Amazon Web Services > >> > > >> > Vancouver, Canada > >> > > >> > > >> > > >> > >> > > > > >> > > > > >> > > > >> > > >> > >> > >> > >> -- > >> Yizhi Liu > >> DMLC member > >> Amazon Web Services > >> Vancouver, Canada > >> > > > > >
