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https://issues.apache.org/jira/browse/CASSANDRA-8984?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=14381708#comment-14381708
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Benedict commented on CASSANDRA-8984:
-------------------------------------
bq. in a stable release.
Well, our release page doesn't quite agree with this implicit assertion (that
2.1 is stable) - but like I say, we can accept the risk as stands and just try
to patch it up as necessary. I'm more keen to fix them than others since I've
taken the heat of the failures, but I'm comfortable so long as I've put my
version of the future out there and highlighted my concerns.
[~JoshuaMcKenzie]: I've pushed a small update that I expect fixes the Windows
issue (though looking forward to automated branch testing so I can corroborate
against Windows directly)
> Introduce Transactional API for behaviours that can corrupt system state
> ------------------------------------------------------------------------
>
> Key: CASSANDRA-8984
> URL: https://issues.apache.org/jira/browse/CASSANDRA-8984
> Project: Cassandra
> Issue Type: Improvement
> Components: Core
> Reporter: Benedict
> Assignee: Benedict
> Fix For: 2.1.4
>
> Attachments: 8984_windows_timeout.txt
>
>
> As a penultimate (and probably final for 2.1, if we agree to introduce it
> there) round of changes to the internals managing sstable writing, I've
> introduced a new API called "Transactional" that I hope will make it much
> easier to write correct behaviour. As things stand we conflate a lot of
> behaviours into methods like "close" - the recent changes unpicked some of
> these, but didn't go far enough. My proposal here introduces an interface
> designed to support four actions (on top of their normal function):
> * prepareToCommit
> * commit
> * abort
> * cleanup
> In normal operation, once we have finished constructing a state change we
> call prepareToCommit; once all such state changes are prepared, we call
> commit. If at any point everything fails, abort is called. In _either_ case,
> cleanup is called at the very last.
> These transactional objects are all AutoCloseable, with the behaviour being
> to rollback any changes unless commit has completed successfully.
> The changes are actually less invasive than it might sound, since we did
> recently introduce abort in some places, as well as have commit like methods.
> This simply formalises the behaviour, and makes it consistent between all
> objects that interact in this way. Much of the code change is boilerplate,
> such as moving an object into a try-declaration, although the change is still
> non-trivial. What it _does_ do is eliminate a _lot_ of special casing that we
> have had since 2.1 was released. The data tracker API changes and compaction
> leftover cleanups should finish the job with making this much easier to
> reason about, but this change I think is worthwhile considering for 2.1,
> since we've just overhauled this entire area (and not released these
> changes), and this change is essentially just the finishing touches, so the
> risk is minimal and the potential gains reasonably significant.
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