[2022 Alibaba Summer of Code] Support Snapshot for DLedger

[RongtongJin]

2022 Alibaba Summer of Code

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Timeline

Our Mentor

@RongtongJin jinrongtong@apache.org @tsunghanjacktsai tsaitsunghan@apache.org

Subject

Snapshot is a very important feature for raft protocol. For example, it can greatly shorten the recovery time and delete useless logs in time. Currently, DLedger has not implemented this feature.

@hzh0425 has implemented statemachine feature and the snapshot interface is left.

dledger/src/main/java/io/openmessaging/storage/dledger/statemachine/StateMachine.java

Lines 37 to 52 in 4293093

	/**
	* User defined snapshot generate function, this method will block StateMachine#onApply(Iterator).
	* Call done.run(status) when snapshot finished.
	*
	* @param writer snapshot writer
	* @param done callback
	*/
	void onSnapshotSave(final SnapshotWriter writer, final CompletableFuture<Boolean> done);
	/**
	* User defined snapshot load function.
	*
	* @param reader snapshot reader
	* @return true on success
	*/
	boolean onSnapshotLoad(final SnapshotReader reader);

Welcome to implement snapshot feature for dledger on this basis and improve the log deletion strategy in state machine mode

difficulty

Advanced (10000 Yuan)

Apply Now

Upload your CV and project proposal via ASOC 2022 official website：
https://opensource.alibaba.com/asoc2022

If you have any questions, visit the event website:https://opensource.alibaba.com/asoc2022

Email address: opensource@alibaba-inc.com

[yanchaomei]

Hi, I want to take over this issue.

[hzh0425]

Hi, I want to take over this issue.

Welcome, you can write an rfc to illustrate your ideas

[ravig-kant]

Hi, I want to take over this issue.

I also wish to contribute to this issue. Can we work on it together?

[RongtongJin]

Hi, I want to take over this issue.

I also wish to contribute to this issue. Can we work on it together?

Of course.

[RongtongJin]

I have put this issue to ASoC. Welcome to apply for this subject!

[TheR1sing3un]

I have put this issue to ASoC. Welcome to apply for this subject!

Hello, does anyone have been doing this project? I am also more interested in this.

[RongtongJin]

I have put this issue to ASoC. Welcome to apply for this subject!

Hello, does anyone have been doing this project? I am also more interested in this.

Not yet. Welcome to write an rfc to illustrate your ideas.