Support LSM in snapshot-converter and streaming ledger tables (#1603)

Closes #1592
Closes #1602

Author: jasagredo

docs/website/contents/references/miscellaneous/utxo-hd/migrating.mdx

@@ -142,7 +142,7 @@ follows:
 </Tabs>
 </div>
 
-## Convert the existing Ledger snapshots with `snapshot-converter`
+## Upgrading a Ledger snapshots from 10.4.x to 10.5.x
 
 :::warning
 
@@ -157,8 +157,29 @@ chain from Genesis, however this can take some hours.
 
 We provide the `snapshot-converter` tool which can load a snapshot in the Legacy
 format and write it either in the in-memory or on-disk formats for
-UTxO-HD. Supposing you have copied a legacy snapshot to
-`<tmpdir>/snapshots/<slotno>` you can run the following command:
+UTxO-HD.
+
+:::info
+
+On cardano-node 10.6 there was a change in serialization unrelated to the
+UTxO-HD changes. This means that going from 10.4.x to 10.5.x can benefit from
+this doing a quick conversion using `snapshot-converter` as explained here, but
+it won't work when the target is 10.6 or newer. Such a format update can
+only be done via a replay of the chain.
+
+The `snapshot-converter` tool still exists in the repository and will convert
+between the different UTxO-HD formats but it will no longer be able to load a
+snapshot older than 10.6, and therefore it won't be able to "upgrade" a Legacy
+snapshot to a UTxO-HD snapshot anymore.
+
+For this reason, the process below is only useful for upgrading from 10.4.x to
+10.5.x, and **it must be performed with the `snapshot-converter` version that
+was released with nodes 10.5.x**.
+
+:::
+
+Supposing you have copied a legacy snapshot to `<tmpdir>/snapshots/<slotno>` you
+can run the following command:
 
 <div class="tabsblock">
 <Tabs>

ouroboros-consensus-cardano/README.md

@@ -20,6 +20,8 @@ This package also contains a few executables:
 
 * `app/immdb-server.hs`: serve an immutable DB via ChainSync and BlockFetch.
 
+* `app/snapshot-converter.hs`: converts snapshots among different storage formats.
+
 ### Assertions
 
 Our top level `cabal.project` enables assertions in both our local packages
@@ -378,3 +380,23 @@ To point a node to a running ImmDB server, use a topology file like
   ]
 }
 ```
+
+
+## snapshot-converter
+
+## About
+
+This tool converts snapshots among the different backends supported by the node.
+
+## Running the tool
+
+Invoking the tool follows the same simple pattern always:
+
+```sh
+cabal run snapshot-converter -- <IN> <OUT> --config /path/to/cardano/config.json
+```
+
+The `<IN>` and `<OUT>` parameters depend on the input and output format, receiving options:
+- `--mem-in PATH`/`--mem-out PATH` for InMemory
+- `--lmdb-in PATH`/`--lmdb-out PATH` for LMDB
+- `--lsm-database-in DB_PATH --lsm-snapshot-in PATH`/`--lsm-database-out DB_PATH --lsm-snapshot-out PATH` for LSM-trees.