// ------------------------------------

      // STEP 1. Try to acquire as many locks as we can, and ensure

      // we acquire at least one.

      // ----------------------------------

      // ------------------------------------

      // STEP 2. Update any LATEST_TIMESTAMP timestamps

      // ----------------------------------

      // ------------------------------------

      // STEP 3. Build WAL edit

      // ----------------------------------

      // -------------------------

      // STEP 4. Append the final edit to WAL. Do not sync wal.

      // -------------------------

      // ------------------------------------

      // STEP 5. Write back to memstore

      // Write to memstore. It is ok to write to memstore

      // first without syncing the WAL because we do not roll

      // forward the memstore MVCC. The MVCC will be moved up when

      // the complete operation is done. These changes are not yet

      // visible to scanners till we update the MVCC. The MVCC is

      // moved only when the sync is complete.

      // ----------------------------------

      // -------------------------------

      // STEP 6. Release row locks, etc.

      // -------------------------------

      // -------------------------

      // STEP 7. Sync wal.

      // -------------------------

      // ------------------------------------------------------------------

      // STEP 8. Advance mvcc. This will make this put visible to scanners and getters.

      // ------------------------------------------------------------------

      // ------------------------------------

      // STEP 9. Run coprocessor post hooks. This should be done after the wal is

      // synced so that the coprocessor contract is adhered to.

      // ------------------------------------

      // if the wal sync was unsuccessful, remove keys from memstore