Draft: Slim accounts

[quocle108]

Change Description

This MR introduces a significant optimization in RAM usage by implementing a new account structure. The changes are designed to enhance efficiency and reduce the memory. The key modifications include:

• Restructure account_object and account_metadata_object. The account_object is now universal for all account types, while the account_metadata_object is specifically applied for smart contract accounts
• Merge Object: resource_limits_object and resource_usage_object into resource_object, permission_object and permission_usage_object into permission_object
• Introduction of Slim Accounts:: To further economize RAM usage, the concept of 'Slim accounts' is introduced. These accounts are smaller, containing only the account_object, resource_object, and one ACTIVE permission. Unlike regular accounts, Slim accounts don't have the ACTIVE permission by default. A Slim account uses up to 54% less RAM than a regular account.

API Changes

• API Changes
  New actions: eosio:: newslimacc

Documentation Additions

• Documentation Additions
  Documentation can be found here

Note

There is an unresolved issues:

• State History Issue: When creating an account, the permissions returned do not match the expected permissions in state history unit-test.

[cc32d9]

as discussed in the chat:

1. namespace reservation must not be hardcoded. It needs a configurable way, if needed at all:

     // system account only can be created by newaccount
      EOS_ASSERT( name_str.find( "eosio." ) != 0, action_validate_exception,
                     "only newaccount action can create account with name start with 'eosio.'" );

2. Odd placement of create_slim_account() inside libraries/chain/webassembly/privileged.cpp. It belongs where newaccount() sits.

3. State history plugin needs to be able to read the data created by previous Leap versions.