Currently, graceful exit is a complicated subsystem that keeps a queue
of all pieces expected to be on a node, and asks the node to transfer
those pieces to other nodes one by one. The complexity of the system
has, unfortunately, led to numerous bugs and unexpected behaviors.
We have decided to remove this entire subsystem and restructure graceful
exit as follows:
* Nodes will signal their intent to exit gracefully
* The satellite will not send any new pieces to gracefully exiting nodes
* Pieces on gracefully exiting nodes will be considered by the repair
subsystem as "retrievable but unhealthy". They will be repaired off of
the exiting node as needed.
* After one month (with an appropriately high online score), the node
will be considered exited, and held amounts for the node will be
released. The repair worker will continue to fetch pieces from the
node as long as the node stays online.
* If, at the end of the month, a node's online score is below a certain
threshold, its graceful exit will fail.
Refs: https://github.com/storj/storj/issues/6042
Change-Id: I52d4e07a4198e9cb2adf5e6cee2cb64d6f9f426b
Remove the logic associated to the old transfer queue.
A new transfer queue (gracefulexit_segment_transfer_queue) has been created for migration to segmentLoop.
Transfers from the old queue were not moved to the new queue.
Instead, it was still used for nodes which have initiated graceful exit before migration.
There is no such node left, so we can remove all this logic.
In a next step, we will drop the table.
Change-Id: I3aa9bc29b76065d34b57a73f6e9c9d0297587f54
For being able to use the segment metainfo loop, graceful exit transfers have to include the segment stream_id/position instead of the path. For this, we created a new table graceful_exit_segment_transfer_queue that will replace the graceful_exit_transfer_queue. The table has been created in a previous migration.
This change gives access to this table.
Graceful Exit doesn't use the table yet, this will be done in a next change.
Change-Id: I6c09cff4cc45f0529813a8898ddb2d14aadb2cb8
Use the 'AS OF SYSTEM TIME' Cockroach DB clause for the Graceful Exit
(a.k.a GE) queries that count the delete the GE queue items of nodes
which have already exited the network.
Split the subquery used for deleting all the transfer queue items of
nodes which has exited when CRDB is used and batch the queries because
CRDB struggles when executing in a single query unlike Postgres.
The new test which has been added to this commit to verify the CRDB
batch logic for deleting all the transfer queue items of the exited
nodes has raised that the Enqueue method has to run in baches when CRDB
is used otherwise CRDB has return the error "driver: bad connection"
when a big a amount of items are passed to be enqueued. This error
didn't happen with the current test implementation it was with an
initial one that it was creating a big amount of exited nodes and
transfer queue items for those nodes.
Change-Id: I6a099cdbc515a240596bc93141fea3182c2e50a9
metabase has become a central concept and it's more suitable for it to
be directly nested under satellite rather than being part of metainfo.
metainfo is going to be the "endpoint" logic for handling requests.
Change-Id: I53770d6761ac1e9a1283b5aa68f471b21e784198
The new 'consistency ge-cleanup-orphaned-data' cli command deleted
orphaned transfer queue items, but not entries in the
graceful_exit_progress table. This will delete orphaned entries
from the exit progress table too.
Change-Id: I5f927aac1f258490678deaf179be92ccfe10fcd8
Add a command to the satellite for cleaning up the Graceful Exit (a.k.a
GE) transfer queue items of nodes that have exited.
The commit adds to the GE satellite DB a couple of new methods, and its
corresponding test, for performing the operations of the new command.
Change-Id: I29a572a59689d63b24990ac13c52e76d65aaa917
metabaseSegmentKey` TransferQueueItem
We are unifying which name (and type) we are using for value we are
using to point to segment. We want to use `key` instead of `path`.
Dedicated type `metabase.SegmentKey` was created for this purposes also.
This change is doing refactoring around gracefulexit.
Change-Id: I90d51ff087b206179e61d5f1bc95f4709d76f917
