Context:
OS: macOS 12.2.1
Chip: Apple M1 Pro
Node: v16.13.2
rocksdb: 5.2.0
level-rocksdb: 5.0.0

Db options:

const level = require('level-rocksdb');

const db = level('./database', {
    valueEncoding: 'json',
    createIfMissing: false,
    readOnly: true,
});

I stress tested the db.GetMany method with batches of 500 keys as part of a simple node.js express app and after some time the memory usage of process was about 40GB and growing.

let keys: Buffer[] = getKeys(req.keys);
let values: (Value | undefined)[] = await db.getMany(keys);

I then replaced getMany with get and the memory stabilised at about 300MB, with worse performance, of course.

let values: (Value | undefined)[] = await Promise.all(
keys.map(async (k): Promise<(Value | undefined)> => {
    try {
        return await db.get(k);
    } catch(e) {
        return undefined;
    }
}));

The problem reproduces 100%. Do you guys have ideas why this could happen?

cc: @vweevers pinging as I saw you added support for getMany.

Thank you!