This change introduces additional processes to manage snapshot uploading
for E2 snapshots:
## erigon snapshots upload
The `snapshots uploader` command starts a version of erigon customized
for uploading snapshot files to
a remote location.
It breaks the stage execution process after the senders stage and then
uses the snapshot stage to send
uploaded headers, bodies and (in the case of polygon) bor spans and
events to snapshot files. Because
this process avoids execution in run signifigantly faster than a
standard erigon configuration.
The uploader uses rclone to send seedable (100K or 500K blocks) to a
remote storage location specified
in the rclone config file.
The **uploader** is configured to minimize disk usage by doing the
following:
* It removes snapshots once they are loaded
* It aggressively prunes the database once entities are transferred to
snapshots
in addition to this it has the following performance related features:
* maximizes the workers allocated to snapshot processing to improve
throughput
* Can be started from scratch by downloading the latest snapshots from
the remote location to seed processing
## snapshots command
Is a stand alone command for managing remote snapshots it has the
following sub commands
* **cmp** - compare snapshots
* **copy** - copy snapshots
* **verify** - verify snapshots
* **manifest** - manage the manifest file in the root of remote snapshot
locations
* **torrent** - manage snapshot torrent files
This introduces _experimental_ block execution run by embedded Silkworm
API library:
- new command-line option `silkworm.path` to enable the feature by
specifying the path to the Silkworm library
- the Silkworm API shared library is dynamically loaded on-demand
- currently requires to build Silkworm library on the target machine
- available only on Linux at the moment: macOS has issue with [stack
size](https://github.com/golang/go/issues/28024) and Windows would
require [TDM-GCC-64](https://jmeubank.github.io/tdm-gcc/), both need
dedicated effort for an assessment
