Intel Corp. today released a Linux version of the solid-state caching software it acquired from startup Nevex last...
year, rebranding the application as Intel Cache Acceleration Software. The software is a companion to Intel solid-state drives and PCI Express cards.
Cache Acceleration Software (CAS) for Linux 2.0 is the first new caching application released by Intel since it acquired Nevex last October. At the time of the acquisition, Nevex had a CacheWorks application for Windows, but the Linux version was still in beta. Intel released CacheWorks 2.0 -- already in the works when the acquisition closed -- last December. That product is now called CAS for Windows 2.0.
With the Linux version, Intel added the ability to set policy-based application priority to data and support for VMware vMotion.
Like other SSD caching software applications, CAS caches frequently used, or "hot," data in an application server's solid-state storage devices. Applications on the server can quickly access the hot data on the devices and avoid the network hop to shared storage.
Intel calls CAS a "multi-level cache" because it uses dynamic RAM (DRAM) and solid-state drives (SSDs) to hold data. According to Andrew Flint, Intel's CAS product manager, CAS places the most frequently accessed data in the server's DRAM. Data accessed less frequently -- but still considered hot -- goes on the solid-state storage.
CAS caches data in chunks as small as 512 KB. As a file cache, it sees data as files, but promotes and evicts the data in blocks so it can cache smaller blocks of larger files.
The policy-based prioritization feature enables administrators to indicate which applications, files, database tables or virtual machines (VMs) have access to the solid-state storage cache. Applications that require high-performance caching can have exclusive access to those solid-state resources.
"We came at the I/O problem from the application side," Flint said. "Our entire intent on everything we did is to make applications go faster. We do that by caching back-end storage and effectively making back-end storage faster. The intent was always to make the cache highly efficient and provide added application performance, but keep that performance constant because irregular response times really annoy users and get in the way of productivity," he added.
CAS also supports VMware vMotion, which allows the cached data to follow applications migrated between physical hosts if CAS is installed on flash devices accessible to both hosts. CAS can also be installed on a master image, and it will install on each VM that uses that image.
Intel CAS for Linux 2.0 will be generally available by the end of February, and priced on a subscription basis. The Linux enterprise support version is available only for an 800 GB cache, and costs $1,200 per year. The Windows subscription costs $2,000 for a 400 GB cache, and $4,000 for an 800 GB cache.
Intel has qualified CAS on its SSD DC 3700 series of drives and its 910 PCI Express (PCIe) flash cards. The enterprise subscription guarantees support only on the Intel flash devices, but Flint said support for running CAS on non-Intel flash would be considered on a customer-by-customer basis.
Many of Intel's SSD and PCIe competitors have their own caching software, including Fusion-io, STEC, Micron, Sandisk, OCZ and LSI. Like Intel, Fusion-io (ioTurbine), Sandisk (FlashSoft), and OCZ (Sanrad) acquired startups for their SSD caching software.
Mark Peters, a senior analyst at Enterprise Strategy Group, said it is interesting to see Intel become so deeply involved in selling storage devices and software under its brand. "What makes it different, besides the new features and specific functionalities, is that it's not coming from an external software or storage-systems company. It's coming from Intel. Intel has typically stayed behind the curtain as the component manufacturer."