900w表添加索引超过一天还没执行完,如何排查?

表结构:
CREATE TABLE summary (
id bigint(20) NOT NULL AUTO_INCREMENT,
empName varchar(100) DEFAULT NULL,
empUuid varchar(100) DEFAULT NULL,
deptUuid varchar(100) DEFAULT NULL,
deptName varchar(100) DEFAULT NULL,
positionUuid varchar(100) DEFAULT NULL,
positionName varchar(100) DEFAULT NULL,
empGroupUuid varchar(100) DEFAULT NULL,
empGroupName varchar(100) DEFAULT NULL,
versionUuid varchar(100) DEFAULT NULL,
companyUuid varchar(100) DEFAULT NULL,
companyName varchar(100) DEFAULT NULL’,
strokeScore decimal(19,2) DEFAULT NULL,
achieveScore decimal(19,2) DEFAULT NULL,
attendScore decimal(19,2) DEFAULT NULL,
customScore decimal(19,2) DEFAULT NULL,
noReachScore decimal(19,2) DEFAULT NULL,
totalScore decimal(19,2) DEFAULT NULL,
assessDateScore decimal(19,2) DEFAULT NULL,
assessWeekScore decimal(19,2) DEFAULT NULL,
assessMonthScore decimal(19,2) DEFAULT NULL,
cal_dt varchar(50) DEFAULT NULL,
approveScore decimal(19,2) DEFAULT NULL,
PRIMARY KEY (id) /*T![clustered_index] CLUSTERED */,
KEY idx_companyUuid (companyUuid),
KEY idx_empUuid (empUuid),
KEY idx_deptUuid (deptUuid),
KEY idx_positionUuid (positionUuid),
KEY idx_empGroupUuid (empGroupUuid),
KEY idx_versionUuid (versionUuid),
KEY idx_cal_dt (cal_dt)
) ENGINE=InnoDB DEFAULT CHARSET=utf8 COLLATE=utf8_bin;

添加索引语句:
ALTER TABLE summary ADD INDEX idx_cal_dt_companyuuid (cal_dt,companyUuid);

现在的表现是:row_count前350w左右跑的很快,然后涨到480w左右很长时间不动,然后涨到557w左右很长时间又不动了(此时已经过去2天了),感觉再花个几天也能加完