Write Spike Performance Enhancement In Hybrid Storage Systems

摘要

In an embodiment, a hybrid storage array one uses two or more storage device tiers provided by solid state drives (SSDs) and hard disk drives (HDDs). Random writes are collected and written to a write cache extension, such as a portion of the SSD storage tier. The write cache extension absorbs such accesses that would otherwise be written to HDD storage directly. Data structures are created in a cache memory local to an array controller representing the location on the write cache extension to which the writes were committed and a location in the storage system where they were originally intended to go. The write cache extension can be enabled all of the time, or only when the array controller write cache experiences certain operating conditions, such as when its utilization exceeds a predetermined amount. The approach improves the overall performance of the hybrid array.

主权项

1. An information handling apparatus comprising:
a tier-0 storage portion; a tier-1 storage portion having a device access time that is slower than a device access time of the tier-0 storage portion; a write cache extension portion having a device access time that is faster than a device access time of the tier-1 storage portion; a storage cache main portion; and a storage array controller that:
receives a storage command for access to a page of data;detects if the storage command is one of a series of random writes to the tier-1 storage portion, and if so, sequentially write the series of random writes to a block of the write cache extension portion, and subsequently write the block to the tier-1 storage portion when the block has reached a particular size.