Techniques involving flaky path detection

A non-transitory computer readable storage medium storing a set of instructions which, when carried out by computerized circuitry, causes the computerized circuitry to oversee a path between a multipathing driver of a host computer and a volume of a data storage array by performing a method comprising:

• while the multipathing driver of the host computer sends input/output requests (IOs) to the volume of the data storage array on the path, generating an IOs-Over-Period metric based on outcomes of the IOs, the IOs-Over-Period metric providing a measure of IOs per failure over a period of path operation;
• performing a comparison operation which compares the IOs-Over-Period metric to a predefined flaky path range having a predefined lower limit and a predefined upper limit;
• and
• after performing the comparison operation, outputting a detection signal indicating that the path is (i) flaky when the IOs-Over-Period metric falls within the predefined flaky path range and (ii) non-flaky when the IOs-Over-Period metric falls outside of the predefined flaky path rang;
• wherein the IOs sent from the multipathing driver to the volume on the path include a series of small computer system interface (SCSI) commands;
• and
• wherein generating the IOs-Over-Period metric based on the outcomes of the IOs includes assigning a series of monotonically increasing instance numbers to the series of SCSI commands to distinctively identify each SCSI command of the series of SCSI commands with an instance number.

A host apparatus, comprising:

• an interface constructed and arranged to communicate with a data storage array;
• memory constructed and arranged to store a predefined flaky path range having a predefined lower limit and a predefined upper limit;
• and
• a controller coupled to the interface and the memory, the controller being constructed and arranged to:
• while a multipathing driver sends input/output requests (IOs) to a volume of a data storage array on a path through the interface, generating an IOs-Over-Period metric based on outcomes of the IOs, the IOs-Over-Period metric providing a measure of IOs per failure over a period of path operation,
• performing a comparison operation which compares the IOs-Over-Period metric to the predefined flaky path range, and
• after performing the comparison operation, outputting a detection signal indicating that the path is (i) flaky when the IOs-Over-Period metric falls within the predefined flaky path range and (ii) non-flaky when the IOs-Over-Period metric falls outside of the predefined flaky path range;
• wherein the IOs sent from the multipathing driver to the volume on the path include a series of small computer system interface (SCSI) commands;
• and
• wherein the controller, when generating the IOs-Over-Period metric based on the outcomes of the IOs, is constructed and arranged to assign a series of monotonically increasing instance numbers to the series of SCSI commands to distinctively identify each SCSI command of the series of SCSI commands with an instance number.