You are an expert in writing code in many different languages. Your goal is to perform code completion for the following code, keeping in mind the rest of the code and the file meta data.
    Metadata details:
    filename: rocksdb.rs
    path of file: ./repos/namada/crates/apps/src/lib/node/ledger/storage
    
    the code of the file until where you have to start completion: //! The persistent storage in RocksDB.
//!
//! The current storage tree is:
//! - `state`: the latest ledger state
//!   - `ethereum_height`: the height of the last eth block processed by the
//!     oracle
//!   - `eth_events_queue`: a queue of confirmed ethereum events to be processed
//!     in order
//!   - `height`: the last committed block height
//!   - `tx_queue`: txs to be decrypted in the next
    
    fn increase_nofile_limit() -> std::io::Result<Rlim> {
        let (soft, hard) = Resource::NOFILE.get()?;
        tracing::debug!("Current NOFILE limit, soft={}, hard={}", soft, hard);

        let target = std::cmp::min(DEFAULT_NOFILE_LIMIT, hard);
        if soft >= target {
            tracing::debug!(
                "NOFILE limit already large enough, not attempting to increase"
            );
            Ok(soft)
        } else {
            tracing::debug!("Try to increase to {}", target);
            Resource::NOFILE.set(target, target)?;

            let (soft, hard) = Resource::NOFILE.get()?;
            tracing::debug!(
                "Increased NOFILE limit, soft={}, hard={}",
                soft,
                hard
            );
            Ok(soft)
        }
    }