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K2InformaticsGmbH / imem

Clustered in-memory database based on MNESIA with simple SQL layer
http://www.k2informatics.ch/
Apache License 2.0
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ram mode is not respected when a disc file (db) is present in direcotry #295

Closed tgdriph3 closed 5 years ago

tgdriph3 commented 5 years ago

Setup with any application using IMEM (e.g. dderl). Starting from ram mode (means entering cold start) on a system that is down is not respected when a disc file Folder is still present. Could be related to #216. Please investigate.

cc: @c-bik f.y.i.

stoch commented 5 years ago

@tgdriph3 ColdStart support is designed for RAM nodes only. With a disk node, there is no cold start because the data is there already. Likewise, cold start is skipped if a new node is entering a cluster, again because the data is already there on the other node. You can delete the database, configure the node to be RAM based and do a cold start then. To use a cluster snapshot to initialize a disk node today, you need a cluster with one DISK and one RAM node (which you can decomission later). For development, you can work with a single RAM node which always cold starts (on the latest cluster snapshot). Like this, you get a history of database versions from which you can pick one to start.