PVF execution currently has a memory limit of 128MB, which is the same as Cumulus uses for its block import pipeline. While collators execute state transitions by reading parachain data from disk locally, parachain validators must load state proofs into memory. Therefore, they should have a higher memory limit than collators. Otherwise a parachain block that made full use of memory when executed by the collator could fail to be executed by validators. To fix this, we propose increasing the memory limit for PVF execution to 512MB.


```
set_config_with_executor_params {}: set_executor_params(RawOrigin::Root, 
ExecutorParams::from(&[ExecutorParam::MaxMemoryPages(8192)][..]))
```

- hash: `0x1c356149b664ec3f7d89eeb56a3469bd5f468ae7fafa2b13f2423618db6c922e`

- calldata: `0x332e040100200000`

- Submit the preimage for the Fellowship referendum:
[https://polkadot.js.org/apps/?rpc=wss%3A%2F%2Fkusama-rpc.polkadot.io#/extrinsics/decode/0x2000882c001c356149b664ec3f7d89eeb56a3469bd5f468ae7fafa2b13f2423618db6c922e](https://polkadot.js.org/apps/?rpc=wss%3A%2F%2Fkusama-rpc.polkadot.io#/extrinsics/decode/0x2000882c001c356149b664ec3f7d89eeb56a3469bd5f468ae7fafa2b13f2423618db6c922e)

- Open a Fellowship referendum to whitelist the call:
[https://polkadot.js.org/apps/?rpc=wss%3A%2F%2Fkusama-rpc.polkadot.io#/extrinsics/decode/0x17002b0f024076336ce5c2429a0c9ebdc17667391af846008847a8dbc6164ebfc076f172d322000000010a000000](https://polkadot.js.org/apps/?rpc=wss%3A%2F%2Fkusama-rpc.polkadot.io#/extrinsics/decode/0x17002b0f024076336ce5c2429a0c9ebdc17667391af846008847a8dbc6164ebfc076f172d322000000010a000000)

- Submit the preimage for the public referendum:
[https://polkadot.js.org/apps/?rpc=wss%3A%2F%2Fkusama-rpc.polkadot.io#/extrinsics/decode/0x2000282c03332e040100200000](https://polkadot.js.org/apps/?rpc=wss%3A%2F%2Fkusama-rpc.polkadot.io#/extrinsics/decode/0x2000282c03332e040100200000)

- Open a public referendum to dispatch the call:
[https://polkadot.js.org/apps/?rpc=wss%3A%2F%2Fkusama-rpc.polkadot.io#/extrinsics/decode/0x15002b0d020ebe5ce9abcaf0e08e88086b99882b0f63862ee2c48f15f84c9c6658526a12d20a000000010a000000](https://polkadot.js.org/apps/?rpc=wss%3A%2F%2Fkusama-rpc.polkadot.io#/extrinsics/decode/0x15002b0d020ebe5ce9abcaf0e08e88086b99882b0f63862ee2c48f15f84c9c6658526a12d20a000000010a000000)


- PVF execution currently has a memory limit of 128MB, same as Cumulus uses for its block import pipeline. 
- Parachain validators must load state proofs into memory, so should have a higher memory limit than collators. 
- This encourages full use of memory when executed by collators, to prevent failing to be executed by validators.
- It is proposed to increase the memory limit for PVF execution to 512MB. 
- To do this, there are two referendums: Fellowship to whitelist the call, and Public to dispatch it.

#233 Increase MaxMemoryPages to 512MB