Performing the following (note the range of 10,000):

`importmulti '[{"desc": "sh(wpkh([aeee1e6a/49h/1h/0h]tpubDC5bVdaveQYxGFztMShFAjU637kKjrs9FD8ne1oHR7z8tLeQJExsaxWRVeSpcCcYMdp5ecf2LQhuVaeYFZ7YEpvWTJr4nDGUJrmuvLuTSsp/1/*))", "keypool": true, "timestamp": "now", "watchonly": true, "internal": true, "range": {"end": 1000}}]' '{"rescan": false}'`

takes many minutes. @achow101 reports a similar import taking 6 minutes on his machine.
throw std::runtime_error(strprintf("BerkeleyBatch: Failed to configure for no temp file backing for database %s", strFilename));
                }
            }
            ret = pdb_temp->open(nullptr,                             
                            fMockDb ? nullptr : strFilename.c_str(),  
                            fMockDb ? strFilename.c_str() : "main",   
                            DB_BTREE,                                 
                            nFlags,                                   
                            0);
            if (ret != 0) {
                throw std::runtime_error(strprintf("BerkeleyBatch: Error %d, can't open database %s", ret, strFilename));
            }
            
            
            
            
            
            
            
            
            
            
            
            
            
            
            
            for (const auto& env : g_dbenvs) {
                CheckUniqueFileid(*env.second.lock().get(), strFilename, *pdb_temp, this->env->m_fileids[strFilename]);
            }