CacheVault Flash Cache

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This article describes the function of the LSI CacheVault Technology. It is a similar technology to Adaptec Zero Maintenance Cache Protection (ZMCP).

How it works

In this photo we see an SAS 9260CV-8i controller which is connected with a cable to the power module (above). The power module ensures the necessary power with the help of capacitors for writing the cache data into the flash storage.
In traditional RAID controllers a BBU (Battery Backup Unit) protects the contents of the cache. The cache contents are retained, because the cache modules are supplied with power from the extra battery in case of a power outage. When the battery is empty, (usually within 72 hours), the contents of the cache will be lost.

No battery is used with CacheVault technology. The cache content is protected by the following systems:

  • A double-layer capacitor is connected to the RAID controller.
  • This will be fully loaded automatically during server startup.
  • In case of power failure the RAID controller uses the power of the capacitor to write the Flash-Memory to maintain all contents of the cache non-volatile (almost like a USB stick).
  • The next time the server is started the RAID controller writes the data from the Flash-Memory to the RAID Array.

Some advantages compared to a BBU:

  • A traditional BBU loses cached data after 72 hours without restored power. CacheVault technology stores the contents of DRAM on NAND flash for up to three years.
  • No BBU/battery replacement necessary
  • 3 years of guaranty instead of 1 year for BBUs

Controller with CacheVault

Controller with optional CacheVault Module

CacheVault Module LSICVM01 (LSI00297).
Am CacheVault Module LSICVM01 connected capacitor.

The following controllers are available as options CacheVault Module LSICVM01 (LSI00297).

Video Showing CacheVault

Additional Information

Related articles

LSI RAID Monitoring Plugin
Smartmontools with MegaRAID Controller