2015-10-28 07:25 AM
Is there any way to allow Flash pool to use all of its capacity, at least for read caching?
This system is running ontap 8.3.1
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2015-11-17 11:55 AM
The maximum size of the Flash Pool cache per system is a function of the controller model and the Data ONTAP release in use. In addition, when both Flash Pool and Flash Cache are used on the same system, the maximum cache size for each caching solution applies, as does the total maximum cache value for the combined use. For details refer section 3.3 Maximum Cache Capacities of the TR-4070. You can refer Hardware Universe to get the specifications for the controller model that you are currently using.
For eg: I have pasted a copy of the limits for the FAS 8060 controller running cDOT 8.3.1.
So even if your system has more cache, only the allowed maximum will be used. Hope this helps.
2015-12-07 04:21 AM
Did you try to set the read and write caching for flashpool as per the caching policies defined in the section 2.4 of the same TR-4070?
Note: NetApp recommends using the default Flash Pool read cache policy. The Flash Pool cache dynamically allocates caching capacity based on the I/O demands put upon the volumes in the aggregate. With the exception of excluding one or more volumes from using the cache, the default "random-read" cache policy should suffice for the vast majority of workloads.