I am using ScyllaDB and have a table called product with a column stock. When the stock changes, I perform a query to select the current stock, then calculate and update the new value in the database. However, when there are multiple concurrent requests, the calculations become incorrect.

When I stress test on my Scylla inside a docker I can’t get more than 2000 successful write per second and write requests more than that will lead to time out even though I have dedicated a lot of resources but Scylla doesn’t use much of it.

When using Size-Tiered Compaction Strategy (STCS) for Scylla, how to decide what value of tombstone_compaction_interval to use? https://opensource.docs.scylladb.com/stable/cql/compaction.html#common-options