Workload selection and cache capacity planning for a virtual storage area network

A non-transitory computer-readable medium storing instructions, which when executed by a processing device, cause the processing device to perform a method comprising:

• receiving a first input/output (I/O) trace including storage addresses that were subject to a plurality of I/O requests from a first workload during a first period of time;
• using the first I/O trace as an input to a cache simulation using a plurality of simulated cache sizes;
• storing a first state of the cache simulation upon completing a simulation of the first I/O trace wherein the first state is a result of the cache simulation;
• deleting the first I/O trace in response to storing the first state of the cache simulation;
• receiving a second I/O trace including storage addresses that were subject to a plurality of I/O requests from the first workload during a second period of time;
• generating an cumulative miss ratio curve (MRC) for the first workload by loading the stored first state as a starting point for simulating the second I/O trace and running the second I/O trace through the cache simulation from the starting point;
• receiving a plurality of I/O traces including storage addresses that were subject to a plurality of I/O requests from a second workload;
• determining an cumulative MRC for the second workload by running the plurality of I/O traces from the second workload through the cache simulation;
• receiving user selection of a first target miss rate for the first workload and a second target miss rate for the second workload;
• generating a recommended cache size that corresponds to the first and second target miss rates based upon the target miss rates and corresponding MRCs;
• and
• allocating an amount of a cache of a virtual storage area network (VSAN) based on the recommended cache size.

An apparatus comprising:

• a processor;
• and
• a hardware memory coupled to the processor, the hardware memory storing instructions which, when executed by the processor, cause the apparatus to:
• receive a first input/output (I/O) trace including storage addresses that were subject to a plurality of I/O requests from a first workload during a first period of time;
• use the first I/O trace as an input to a cache simulation using a plurality of simulated cache sizes;
• store a first state of the cache simulation upon completing a simulation of the first I/O trace wherein the first state is a result of the cache simulation;
• delete the first I/O trace in response to storing the first state of the cache simulation;
• receive a second I/O trace including storage addresses that were subject to a plurality of I/O requests from the first workload during a second period of time;
• generate an cumulative miss ratio curve (MRC) for the first workload by loading the stored first state as a starting point for simulating the second I/O trace and running the second I/O trace through the cache simulation from the starting point;
• receive a plurality of I/O traces including storage addresses that were subject to a plurality of I/O requests from a second workload;
• determine an cumulative MRC for the second workload by running the plurality of I/O traces from the second workload through the cache simulation;
• receive user selection of a first target miss rate for the first workload and a second target miss rate for the second workload;
• generate a recommended cache size that corresponds to the first and second target miss rates based upon the target miss rates and corresponding MRCs;
• and
• allocate an amount of a cache of a virtual storage area network (VSAN) based on the recommended cache size.