Use of error correction-based metric for identifying poorly performing data storage devices

A method for identifying a poorly performing data storage device (DSD) from a plurality of affiliated DSDs constituent to a data storage system, the method comprising:

• periodically polling a set of error counters for the plurality of DSDs;
• based on the error counters, determining a value for a lifetime Quality of Service (QoS) metric for each respective DSD of a plurality of DSDs, wherein each lifetime QoS value is based on an average percentage of total bytes processed over a lifetime of each respective DSD without the respective DSD performing an autonomous error correction;
• and
• recording each lifetime QoS value for the polling period.

A data storage system comprising:

• a system controller circuitry comprising memory and one or more processors and embodying one or more sequences of instructions which, when executed by the one or more processors, cause performance of:
• retrieving a respective set of error log pages from each of a plurality of data storage devices (DSDs);
• based on each respective set of error log pages, determining a value for a Quality of Service (QoS) metric for each respective DSD of the plurality of DSDs, wherein each QoS value represents a percentage of total bytes processed without the respective DSD performing an autonomous error correction;
• determining whether each DSD QoS value reaches a predetermined QoS threshold value;
• and
• in response to a particular DSD QoS value reaching the predetermined QoS threshold value, determining whether to perform an in-situ repair for the particular DSD or to add the particular DSD to a list of candidate DSDs for further Full Recoveries Per Hour (FRPH) examination.

A data storage system comprising:

• a plurality of data storage devices (DSDs);
• means for retrieving a respective set of SCSI (Small Computer System Interface) log pages from each of the plurality of data storage devices (DSDs);
• means for determining, based on each respective set of SCSI log pages, a value for a Quality of Service (QoS) metric for each respective DSD of the plurality of DSDs, wherein each QoS value represents a percentage of total bytes processed without the respective DSD performing an autonomous error correction;
• means for determining whether each DSD QoS value reaches a predetermined QoS threshold value;
• and
• means for determining, in response to a particular DSD QoS value reaching the predetermined QoS threshold value, whether to perform an in-situ repair for the particular DSD or to add the particular DSD to a list of candidate DSDs for further Full Recoveries Per Hour (FRPH) examination.