System, method and computer readable medium for obtaining consistent read performance for a plurality of flash drives or raid groups using workload and capacity limits

A system comprising:

• a processor;
• and
• a memory comprising code stored thereon that, when executed, performs a method of obtaining consistent read performance comprising:
• receiving a plurality of measured read input/output (I/O) response times, each of the plurality of measured read I/O response times denoting a measured read I/O response time for a different one of a plurality of RAID groups, each of the plurality of RAID groups including flash storage devices of a same technology and a same capacity;
• determining, in accordance with a specified allowable variation, whether a first of the plurality of measured read I/O response times for a first of the plurality of RAID groups is inconsistent with respect to other ones of the plurality of measured read I/O response times;
• and
• responsive to determining the first measured read I/O response time is inconsistent with respect to other ones of the plurality of measured read I/O response times, performing first processing that corrects or alleviates the inconsistency of the first measured read I/O response time, the first processing including varying the first measured read I/O response time of the first RAID group by enforcing, for the first RAID group, a write I/O workload limit, a read I/O workload limit, and an idle capacity limit.

A non-transitory computer readable medium comprising code stored thereon that, when executed, performs a method of obtaining consistent read performance comprising:

• receiving a plurality of measured read input/output (I/O) response times, each of the plurality of measured read I/O response times denoting a measured read I/O response time for a different one of a plurality of flash storage devices;
• determining, in accordance with a specified allowable variation, whether a first of the plurality of measured read I/O response times for a first of the plurality of flash storage devices is inconsistent with respect to other ones of the plurality of measured read I/O response times;
• and
• responsive to determining the first measured read I/O response time is inconsistent with respect to other ones of the plurality of measured read I/O response times, performing first processing that corrects or alleviates the inconsistency of the first measured read I/O response time, the first processing including varying the first measured read I/O response time of the first flash storage device by enforcing, for the first flash storage device, a write I/O workload limit, a read I/O workload limit, and an idle capacity limit.