Java 8 end of life for gRPC ?

[Russell Shaw]

Regarding the below comment in recent release notes..

"Java 8 users pay note: per gRFC P5, gRPC may drop Java 8 support as soon as March this year. If this is expected to cause undue hardship or community issues, please contact us via a GitHub issue or grp...@googlegroups.com."

Our company uses Java8 on Z/OS, and uses Google PubSub (which internally uses gRPCJava) to send to GCP cloud environments.

I am guessing that the final gRPCJava version built via Java 8, will still be able to talk to Pubsub for a while, until the PubSub/gRPC protocols changes enough that it eventually breaks.

What are the chances of this happening ? 

ie Are the protocols basically set and therefore won't break ?

Is there any Google Cloud Platform information on "no longer supported" versions of Pubsub / grpcjava  jars / cloud-boms? I can't find it mentioned.

Cheers, Russell

Russell Shaw 
Software Engineer - Career 

Acro Database Support
Equifax Inc.

O 470-750-2979 Ext.32444

C 678-243-8579
russel...@equifax.com

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[Eric Anderson]

On Fri, Jan 28, 2022 at 7:19 AM 'Russell Shaw' via grpc.io <grp...@googlegroups.com> wrote:

Our company uses Java8 on Z/OS

The TL;DR for all this stuff is probably: For Google Cloud users, overall I'd expect service-specific issues to crop up more than gRPC compatibility issues. For example, if you want to use a new service, the library may only support Java 11+. But you really want a plan to upgrade to Java 11 and beyond.

Thank you so much for the email. We really do want to hear trouble caused, as otherwise there's no feedback loop. Sorry for the delay, your email was just brought to my attention.

In your specific case, it looks like IBM's Java 11 was only recently made available? That's a bit worrisome, as it only buys you 1.5 more years, as end of Premier Support of Java 11 is rapidly approaching. I'm going to need to keep an eye on that. But you aren't blocked, right? It is just "gotta move quickly"?

I'll note that practically speaking I doubt we'll actually drop Java 8 in March. I mainly wanted people to realize that we could, because we really need to have these conversations now and then when we delay it is perceived as niceness :-). I expect gRPC will wait until ~June before dropping Java 8, because dropping Java 8 hasn't been on user's radar until recently.

But that may not hold for the rest of the Google client libraries. You as a Google Cloud library consumer are intended to be insulated from gRPC, so you should really only need to track the Google Cloud libraries.

I am guessing that the final gRPCJava version built via Java 8, will still be able to talk to Pubsub for a while, until the PubSub/gRPC protocols changes enough that it eventually breaks.

In that case Pubsub support policies still apply. See Google's Java supported version documentation.

gRPC v1.44.0 is still compatible with v1.0.0. A backward incompatible change would be a big deal and probably need a multi-year migration process. I know of no features currently discussed that would need to break the protocol. (Sure, a new feature may need both sides to be upgraded to be used, but then you just wouldn't benefit from the feature.) I wouldn't be concerned about protocol breakages in the low-single-digit years time frame.

There could, however, be behavior changes which don't impact correctness but could impact performance or similar. This is less likely about gRPC specific implementation but instead the HTTP/2 ecosystem or auth or $SOME_OTHER_NON_GRPC_BUT_RELATED topic. These are managed by the Google service support policies. Google will almost certainly try to avoid these, but if something crops up you'd go through the Google support processes. Not speaking authoritatively, but if there's a case of 1-5% performance decrease, then that just may be the price paid. But something like a 75% decrease is more like a service deprecation with notifications, etc. Google can track usage of the old versions via the User-Agent.

Is there any Google Cloud Platform information on "no longer supported" versions of Pubsub / grpcjava  jars / cloud-boms? I can't find it mentioned.

I thought I had seen something about library versions being supported for a year, but it might be in support contracts or similar non-public documentation, or I just may be wrong. The Java version support policy does clearly define that the Java 7 releases are best effort. I'd expect Java 8 to be included in that when it reaches its EOL.

[Russell Shaw]

So if we meet our migration target to move application for Z/OS to GCP this year, then I think we should be fine

Either way, it sound like Java 8 pubsub client will still be fine in the meantime

Russell Shaw 
Software Engineer - Career 

Acro Database Support
Equifax Inc.

O 470-750-2979 Ext.32444

C 678-243-8579
russel...@equifax.com