Feeds

Explained: How LSI and Oracle cooked up magical flash-embiggening sauce

It’s all about compression, baby

7 Elements of Radically Simple OS Migration

Oracle and LSI have magicked up a way for LSI’s Nytro server flash cards to hold more data than they’re seemingly physically capable of holding and called it Dynamic Logical Capacity (DLC). How does it work?

We thought it might be a paging mechanism – but we were dead wrong. The card compresses the data it is sent and can reach a 2:1 compression ratio, depending on the data. With 50 per cent compression of the data, a 1TB Nytro card can hold 2TB of raw data.

This increases cache-hit rates and thereby increases server application performance. It reduces the cost/GB of the Nytro PCIe flash card storage and also the GB/watt measure. LSI says the compression is used for write amplification reduction as well as capacity extension.

The Nytro card reports its free space via an API, enabling the host system to send data up to the point its free capacity is used up. With the reporting OEMs can utilise DLC technology:

  • APIs are used by host software to monitor usable Virtual Capacity
  • It needs close coordination between the Nytro PCIe flash card and the application
  • The application must monitor free flash space to maintain optimal performance and to guard against free flash space exhaustion.

LSI points out that the card’s logical space varies over time as the cached data’s compressibility changes.

El Reg’s storage desk was hit by a severe case of rear view recognition: Of course! Shouldn’t all flash cards be doing this? We expect they will. ®

Best practices for enterprise data

More from The Register

next story
Microsoft's Euro cloud darkens: US FEDS can dig into foreign servers
They're not emails, they're business records, says court
Sysadmin Day 2014: Quick, there's still time to get the beers in
He walked over the broken glass, killed the thugs... and er... reconnected the cables*
VMware builds product executables on 50 Mac Minis
And goes to the Genius Bar for support
Multipath TCP speeds up the internet so much that security breaks
Black Hat research says proposed protocol will bork network probes, flummox firewalls
Auntie remains MYSTIFIED by that weekend BBC iPlayer and website outage
Still doing 'forensics' on the caching layer – Beeb digi wonk
Microsoft says 'weird things' can happen during Windows Server 2003 migrations
Fix coming for bug that makes Kerberos croak when you run two domain controllers
Cisco says network virtualisation won't pay off everywhere
Another sign of strain in the Borg/VMware relationship?
prev story

Whitepapers

7 Elements of Radically Simple OS Migration
Avoid the typical headaches of OS migration during your next project by learning about 7 elements of radically simple OS migration.
Implementing global e-invoicing with guaranteed legal certainty
Explaining the role local tax compliance plays in successful supply chain management and e-business and how leading global brands are addressing this.
Consolidation: The Foundation for IT Business Transformation
In this whitepaper learn how effective consolidation of IT and business resources can enable multiple, meaningful business benefits.
Solving today's distributed Big Data backup challenges
Enable IT efficiency and allow a firm to access and reuse corporate information for competitive advantage, ultimately changing business outcomes.
A new approach to endpoint data protection
What is the best way to ensure comprehensive visibility, management, and control of information on both company-owned and employee-owned devices?