Hi Matthias,

I don't use externalized checkpoints (from Flink UI Persist Checkpoints 
Externally: Disabled), why do you think checkpoint(s) should be retained? It 
kind of contradicts with documentation [1] - Checkpoints are by default not 
retained and are only used to resume a job from failures.

[1] - 
https://ci.apache.org/projects/flink/flink-docs-master/docs/ops/state/checkpoints/#retained-checkpoints
Checkpoints | Apache 
Flink<https://ci.apache.org/projects/flink/flink-docs-master/docs/ops/state/checkpoints/#retained-checkpoints>
Checkpoints # Overview # Checkpoints make state in Flink fault tolerant by 
allowing state and the corresponding stream positions to be recovered, thereby 
giving the application the same semantics as a failure-free execution. See 
Checkpointing for how to enable and configure checkpoints for your program. 
Checkpoint Storage # When checkpointing is enabled, managed state is persisted 
to ensure ...
ci.apache.org

Thanks,
Alexey
________________________________
From: Matthias Pohl <matth...@ververica.com>
Sent: Thursday, August 26, 2021 5:42 AM
To: Alexey Trenikhun <yen...@msn.com>
Cc: Flink User Mail List <user@flink.apache.org>; sjwies...@gmail.com 
<sjwies...@gmail.com>
Subject: Re: checkpoints/.../shared cleanup

Hi Alexey,
thanks for reaching out to the community. I have a question: What do you mean 
by "the shared subfolder still grows"? As far as I understand, the shared 
folder contains the state of incremental checkpoints. If you cancel the 
corresponding job and start a new job from one of the retained incremental 
checkpoints, it is required for the shared folder of the previous job to be 
still around since it contains the state. The new job would then create its own 
shared subfolder. Any new incremental checkpoints will write their state into 
the new job's shared subfolder while still relying on shared state of the 
previous job for older data. The RocksDB Backend is in charge of consolidating 
the incremental state.

Hence, you should be careful with removing the shared folder in case you're 
planning to restart the job later on.

I'm adding Seth to this thread. He might have more insights and/or correct my 
limited knowledge of the incremental checkpoint process.

Best,
Matthias

On Wed, Aug 25, 2021 at 1:39 AM Alexey Trenikhun 
<yen...@msn.com<mailto:yen...@msn.com>> wrote:
Hello,
I use incremental checkpoints, not externalized, should content of 
checkpoint/.../shared be removed when I cancel job  (or cancel with savepoint). 
Looks like in our case shared continutes to grow...

Thanks,
Alexey

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