while true; do sleep 1h; rpm-ostree compose tree...; done

[Colin Walters]

On Thu, Oct 9, 2014, at 04:33 PM, Paul W. Frields wrote:

> * How often updates should be issued?  Who can decide this?

As often as the yum repository regenerates would be the goal.

> * Which releases are updated, i.e. does the ostree lifecycle differ
>   from standard Fedora?  Does the Atomic team need to check in with
>   FESCo about this?

Let's for now assume we have sync'd lifecycles.
 
> * ...which leads to how much storage is going to be required.  We can
>   get storage, this is an important project and that is not a
>   blocker.  But we can't plan without any idea whatsoever of
>   magnitude.  This has to come from the Atomic team AFAICT.

As I posted elsewhere, we can prune the repository.  We can in fact
have it only take up one commit if we wanted to do so.

Here are some current stats from rawhide:
# ostree --repo=repo log fedora-atomic/rawhide/x86_64/docker-host | grep
commit | wc -l
1276
# du -shc repo/objects/
44G     repo/objects/
44G     total
#

That's an average of 35MB per commit - and most of that honestly is
dracut =/  I need to update rpm-ostree to use the new
--print-depencencies and only rebuild it when it changed.

Let's look at the space from a *single* commit:

# mkdir repo2
# ostree init --repo=repo2 --mode=archive-z2
# rpm-ostree compose tree --repo=repo2
~walters/src/fedora-atomic/fedora-atomic-docker-host.json
...
# du -shc repo2/objects/
397M    repo2/objects/
397M    total

If we wanted to, the repo could use ~400MB and stay at that size if we
limited it to one commit.  I'd prefer keeping two at least though.

> * Was it already figured out how mirrors deal with this content?
>   Please understand the last I heard about the project, there was an
>   issue with the number of HTTP requests involved.  I expect the code
>   has moved on significantly since then.  

There's been some more work yes, but static deltas are not ready yet.

> Is there still some issue
>   for mirrors?

I can't answer that myself.  It seems like something hard to know for
sure until we know how many users hit the mirrors for it.  Note OSTree
is fairly amenable to local caching; certainly if you're booting lots of
servers in say AWS, there's no reason not to mirror the repository
content.