Smart Response Technology

In computing, Smart Response Technology (SRT, also called SSD Caching before it was launched) is a proprietary caching mechanism introduced in 2011 by Intel for their Z68 chipset (for the Sandy Bridge–series processors), which allows a SATA solid-state drive (SSD) to function as cache for a (conventional, magnetic) hard disk drive (HDD).

SRT is managed by Intel Rapid Storage Technology software version 10.5 or later, and implemented both in its device driver and in the Z68 motherboard's firmware (option ROM). It is available only when the (integrated) disk controller is configured in RAID mode (but not AHCI or IDE modes) by implementing a style of RAID 0 striping. The user can select write-back (so-called maximized mode) or write-through (so-called enhanced mode) caching strategy. The maximum utilizable cache size on the SSD is 64 GB. Caching is done at the logical block addressing (LBA) level, not the file level.

Shortly before the announcement of the new chipset, Intel also introduced the Intel 311 (Larson Creek), a 20 GB single-level cell (SLC) solid-state drive, which it markets as suitable for caching. As of 2014^[update], TRIM garbage collection is not supported for SRT caching devices, so the SSD's performance is solely maintained by its own firmware.

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