公开(公告)号：US20170220284A1

公开(公告)日：2017-08-03

申请号：US15011155

申请日：2016-01-29

Applicant: NetApp, Inc.

Inventor： Sharad Jain ,  Sudhindra Prasad Tirupati Nagaraj ,  Vinay Hangud

IPC: G06F3/06 ,  G06F17/30

CPC classification number: G06F3/0631 ,  G06F3/0604 ,  G06F3/061 ,  G06F3/064 ,  G06F3/0644 ,  G06F3/0671 ,  G06F3/0673 ,  G06F3/0683 ,  G06F16/2282

Abstract: Exemplary embodiments address the problem of disk fragmentation by using the heuristics of write operations to assign block sizes. As write requests are received, a storage system may register a size of the write request. Using the registered sizes, the storage system may identify one or more clusters of sizes at which write requests are particularly prevalent. The storage system may calculate a distribution or variance for block sizes centered on each cluster. The distribution or variance may be used to distribute the block sizes such that the block sizes change by a small amount in the vicinity of the cluster, and by a larger amount as the blocks move away from the center of the cluster. When it comes time to allocate new blocks, the clusters and distribution may be consulted to determine what sizes of blocks to allocate, and how many blocks of each size.

公开(公告)号：US20170315928A1

公开(公告)日：2017-11-02

申请号：US15141423

申请日：2016-04-28

Applicant: NetApp, Inc.

Inventor： Vinay Hangud ,  Sharad Jain ,  Sudhindra Prasad Tirupati Nagaraj

IPC: G06F12/12 ,  G06F12/0891

CPC classification number: G06F12/126 ,  G06F12/023 ,  G06F2212/1016 ,  G06F2212/1044 ,  G06F2212/154

Abstract: Exemplary embodiments relate to cache replacement schemes. Incoming data may be sorted into buckets. When it comes time to replace information in the cache, an entire bucket may be eliminated or replaced at once. By sorting incoming data into the buckets and performing cache replacement on a bucket-by-bucket basis, cache fragmentation is reduced. Moreover, the buckets may be scored based on characteristics of the data in the buckets (e.g., whether a data item is cold archived, whether a customer has pinned the data item, or whether the customer has requested early eviction of the data item). By accounting for these metrics when the cache score is calculated, cache usage and hit rates may be improved. According to exemplary embodiments, scoring may be applied to entire buckets, or may be applied to individual cache items (e.g., for use as a cache replacement metric in a cache eviction scheme).

公开(公告)号：US20170315930A1

公开(公告)日：2017-11-02

申请号：US15141447

申请日：2016-04-28

Applicant: NetApp, Inc.

Inventor： Vinay Hangud ,  Sharad Jain ,  Sudhindra Prasad Tirupati Nagaraj

IPC: G06F12/121

CPC classification number: G06F12/121 ,  G06F12/0804 ,  G06F12/0868 ,  G06F2212/1021

Abstract: Exemplary embodiments relate to cache replacement schemes. Incoming data may be sorted into buckets. When it comes time to replace information in the cache, an entire bucket may be eliminated or replaced at once. By sorting incoming data into the buckets and performing cache replacement on a bucket-by-bucket basis, cache fragmentation is reduced. Moreover, the buckets may be scored based on characteristics of the data in the buckets (e.g., whether a data item is cold archived, whether a customer has pinned the data item, or whether the customer has requested early eviction of the data item). By accounting for these metrics when the cache score is calculated, cache usage and hit rates may be improved. According to exemplary embodiments, scoring may be applied to entire buckets, or may be applied to individual cache items (e.g., for use as a cache replacement metric in a cache eviction scheme).