Actually, I tried to say that support *doesn't necessarily* include N-1. I'm proposing that the supported versions are 1) covered by CI and 2) have been available in a usable form long enough that a semi-motivated user has been able to transition to it. That might mean only N (e.g. per my proposal, only cuDNN v7).
Regarding precedent for N / N-1, when a new CUDA version comes out, users will transition to it at their own pace, thereby creating a N / N-1 support situation for some period. On 2019/06/03 22:43:20, Pedro Larroy <[email protected]> wrote: > Your proposal of having support for N and N-1 makes a lot of sense to > me. Are there use cases for supporting older CUDA versions? > > > Thanks. > > On Mon, Jun 3, 2019 at 3:06 PM Dick Carter <[email protected]> wrote: > > > > I'd like to revisit the discussion of: > > https://lists.apache.org/thread.html/27b84e4fc0e0728f2e4ad8b6827d7f996635021a5a4d47b5d3f4dbfb@%3Cdev.mxnet.apache.org%3E > > now that a year has passed. > > > > My motivation is: > > > > 1. There's a lot of hard-to-read '#if CUDNN_MAJOR' code referencing cuDNN > > versions back as far as v4(!?). We need to clean this out before it > > hampers our ability to nimbly move the codebase forward. > > > > 2. There seems to be a difference of opinion on whether we should be > > supporting version 'N-1' (e.g. cuDNN6). Our current MXNet 1.5 candidate > > does not compile against cuDNN v6, so this should be either fixed or be > > up-front stated to the user community. The breaking PR was > > https://github.com/apache/incubator-mxnet/pull/14476. > > > > Having read the prior discussion, my take on it is: > > > > - Users should be given an ample time period (1 year?) to move to a new > > CUDA/cuDNN version once it becomes 'usable.' > > > > - We should not claim to support a given version if it is no longer part of > > the MXNet CI. User's should be warned of an impeding dropping of this > > 'testing support.' > > > > So these statements do not necessarily promise 'N-1' support. I could see > > a transitioning of the CI from CUDA9-only -> CUDA9&10 -> CUDA10 only. Some > > period before CUDA9 is dropped from CI, the user community is warned. > > After that time, CUDA10 might be the only version tested by CI, and hence > > the only version supported (until the next CUDA version came around). > > > > Let me propose as a 'strawman' that we claim to support CUDA version 9 and > > 10, with cuDNN version 7 only. Those versions have been out for over 1.5 > > years. So no CUDA 8 or cuDNN v6 support- over 1.5 years old with no > > coverage by our CI. > > > > -Dick >
