Step 1 On the ISM, manually change the write policy from Write Through to Write Back.
Note: If other faults exist in the storage system, rectify those faults first. Otherwise, the write policy may fail to be changed.
Step 2 If the write policy is already Write Back, run the following command in debug mode to locate the slow disk.
iostat -d -x 2
Step 3 Send the displayed messages to Huawei engineers for further handling.