MULTIPLE LOCALITY-BASED CACHING IN A DATA STORAGE SYSTEM
A data storage caching architecture supports using native local memory such as host-based RAM, and if available, Solid State Disk (SSD) memory for storing pre-cache delta-compression based delta, reference, and independent data by exploiting content locality, temporal locality, and spatial locality of data accesses to primary (e.g. disk-based) storage. The architecture makes excellent use of the physical properties of the different types of memory available (fast r/w RAM, low cost fast read SSD, etc) by applying algorithms to determine what types of data to store in each type of memory. Algorithms include similarity detection, delta compression, least popularly used cache management, conservative insertion and promotion cache replacement, and the like.
1 . A method of content locality-based caching, comprising:
receiving data that is associated with a data storage system with a processor;
processing the data with the processor to determine its content locality;
processing the data with the processor to determine its temporal locality; and
caching a portion of the processed data based on its determined content and temporal locality.
2 . The method of claim 1 wherein the data that is associated with the data storage system is the pre-cache data.
3 . The method of claim 1 wherein the caching includes caching the first portion of the processed data in an SSD memory.
4 . The method of claim 1 wherein the caching comprises caching a first portion of the processed data in a RAM memory.
5 . A method of content locality-based caching, comprising:
receiving data that is associated with a data storage system with a processor;
processing the data with the processor to determine its content locality;
processing the data with the processor to determine its spatial locality; and
caching a portion of the processed data based on its determined content and spatial locality.
6 . The method of claim 5 wherein the data that is associated with the data storage system is pre-cache data.
7 . The method of claim 5 wherein the caching comprises caching a first portion of the processed data in an SSD memory.
8 . The method of claim 5 wherein the caching comprises caching a first portion of the processed data in a RAM.
9 . A method of content locality-based caching, comprising:
receiving data that is associated with a data storage system with a processor;
processing the data with the processor to determine its content locality;
processing the data with the processor to determine its spatial locality;
processing the data with the processor to determine its temporal locality; and
caching a portion of the processed data based on its determined content, spatial, and temporal locality.
10 . The method of claim 9 wherein data that is associated with the data storage system is pre-cache data.
11 . The method of claim 9 wherein the caching comprises caching the first portion of the processed data in an SSD memory.
12 . The method of claim 11 wherein the first portion of the processed data comprises reference blocks.
13 . The method of claim 11 wherein the first portion of the processed data comprises delta blocks.
14 . The method of claim 11 wherein the first portion of the processed data comprises independent blocks.
15 . The method of claim 9 wherein the caching comprises caching a first portion of the processed data in a RAM memory.
16 . The method of claim 15 wherein the first portion of the processed data comprises delta blocks.
17 . The method of claim 15 wherein the first portion of the processed data comprises independent blocks.
18 . The method of claim 9 wherein the caching comprises caching a first portion of the processed data in an HDD memory.
19 . The method of claim 18 wherein the first portion of the processed data comprises delta blocks.
20 . The method of claim 18 wherein the first portion of the processed data comprises independent blocks.