[
https://issues.apache.org/jira/browse/ZOOKEEPER-965?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=12975704#action_12975704
]
Henry Robinson commented on ZOOKEEPER-965:
------------------------------------------
Hi Thomas -
I really appreciate all your hard work cleaning up ZooKeeper's internals. I
understand your frustration about the speed at which some tickets are moving.
You've correctly identified that the committers have limited time, and
particularly so over the holiday season. Hopefully we can pick up the pace now!
However, I'm uncomfortable with the idea that ongoing refactoring work could
block an often asked-for feature like this - particularly a JIRA (911) where
there isn't yet consensus on the approach, or indeed an available patch. Open
source projects see fluctuating participation so we can't afford generally for
issues to come with 'locks' on the code they touch, otherwise we run the risk
of starvation :)
So if this issue gets a patch with consensus before ZOOKEEPER-911, I'll be very
happy to commit it and then to work with you on the extra changes in
ZOOKEEPER-911 that this patch would cause.
Henry
> Need a multi-update command to allow multiple znodes to be updated safely
> -------------------------------------------------------------------------
>
> Key: ZOOKEEPER-965
> URL: https://issues.apache.org/jira/browse/ZOOKEEPER-965
> Project: ZooKeeper
> Issue Type: Bug
> Reporter: Ted Dunning
> Fix For: 3.4.0
>
>
> The basic idea is to have a single method called "multi" that will accept a
> list of create, delete, update or check objects each of which has a desired
> version or file state in the case of create. If all of the version and
> existence constraints can be satisfied, then all updates will be done
> atomically.
> Two API styles have been suggested. One has a list as above and the other
> style has a "Transaction" that allows builder-like methods to build a set of
> updates and a commit method to finalize the transaction. This can trivially
> be reduced to the first kind of API so the list based API style should be
> considered the primitive and the builder style should be implemented as
> syntactic sugar.
> The total size of all the data in all updates and creates in a single
> transaction should be limited to 1MB.
> Implementation-wise this capability can be done using standard ZK internals.
> The changes include:
> - update to ZK clients to all the new call
> - additional wire level request
> - on the server, in the code that converts transactions to idempotent form,
> the code should be slightly extended to convert a list of operations to
> idempotent form.
> - on the client, a down-rev server that rejects the multi-update should be
> detected gracefully and an informative exception should be thrown.
> To facilitate shared development, I have established a github repository at
> https://github.com/tdunning/zookeeper and am happy to extend committer
> status to anyone who agrees to donate their code back to Apache. The final
> patch will be attached to this bug as normal.
--
This message is automatically generated by JIRA.
-
You can reply to this email to add a comment to the issue online.
