Articles by subject: Author: Edouard Haas

NOR vs NAND: So You Think You Know the Music?

In-depth comparison between NOR and NAND covering aspects of NOR and NAND flash technologies that, in our view, are too often ignored including the impact of the application requirements on the choice of Flash technology.

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Road leading to an SD Card shaped sunrise.

Managed vs Unmanaged: The Many Roads to Flash Storage

Let’s explore and compare two different paradigms of flash management commonly used throughout the industry: managed flash and unmanaged flash. Managed flash devices include SD cards, USB flash drives, eMMC and UFS modules — also SSDs, but those are less often seen in embedded systems. These are all NAND-based devices.

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Taming the Flash Beast

This article is the first of an introduction series about flash memory. A high-level introduction shall we say. Not the kind that takes you straight to the electron and drags you through the depths of quantum physics. No. The purpose of this series is to provide useful information from an operational perspective. Things that you

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Code example of implementing a firmware upgrade procedure using TSFS snapshot and revert features.

Firmware Update Implementation Using TSFS Snapshots

In the previous article of this series on TSFS snapshots, we have shown how snapshots can be used to design a simple yet robust firmware upgrade procedure. This time, we go from design to implementation, delving into the specifics of the TSFS snapshot management interface. More specifically, we show how we can meet our initial

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Firmware upgrade procedure block diagram using a snapshot to save the state of the file system prior to beginning the upgrade procedure.

Firmware Upgrade Design Using TSFS Snapshots

This article is the first part of a twofold series on one of the most unique TSFS feature: snapshotting. In this first article, we show how snapshots can ease application development, providing the application designer with an elegant way of handling concurrent read/write accesses. We also introduce a simple firmware update example, to help us

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Timing diagram of various high-level failures that could break the coherence of a data logging application.

Fail-Safe Design with the TREEspan File System Part 3: Enforcing Coherence Through Transactions

In this article, we show that TSFS transactions go beyond preserving file-level integrity, and can also be used to enforce coherence across multiple files and directories. To support the discussion, we present a real-life application example and demonstrate how a single additional call to tsfs_commit() is all that is needed to make the code immune to unexpected failures.

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Time diagram of the protection afforded by a transactional file system against various unexpected failure points during a file update.

Fail-Safe Design with the TREEspan File System Part 2: TSFS Transactions

In this second article in this series we see how an application can be designed to withstand such unforeseen events, using TSFS transactions. Doing so, we introduce the tsfs_commit() API. We also discuss the write transaction atomicity property, by which applications can be safely designed ignoring potential partial update issues.

Read More »
Time diagram of various file system unexpected failures and their impact on data and metadata corruption.

Fail-Safe Design with the TREEspan File System Part 1: Introduction

This is the first article of a three-part series on fail-safe, storage-related application design. The first part of the series lays out the fundamental problem of unexpected failures and briefly discusses partial solutions. The second part introduces the TREEspan File System(TSFS) transactions as a means to protect the application against such potentially disruptive events. Finally,

Read More »

Articles by subject: Author: Edouard Haas

NOR vs NAND: So You Think You Know the Music?

In-depth comparison between NOR and NAND covering aspects of NOR and NAND flash technologies that, in our view, are too often ignored including the impact of the application requirements on the choice of Flash technology.

Read More »
Road leading to an SD Card shaped sunrise.

Managed vs Unmanaged: The Many Roads to Flash Storage

Let’s explore and compare two different paradigms of flash management commonly used throughout the industry: managed flash and unmanaged flash. Managed flash devices include SD cards, USB flash drives, eMMC and UFS modules — also SSDs, but those are less often seen in embedded systems. These are all NAND-based devices.

Read More »

Taming the Flash Beast

This article is the first of an introduction series about flash memory. A high-level introduction shall we say. Not the kind that takes you straight to the electron and drags you through the depths of quantum physics. No. The purpose of this series is to provide useful information from an operational perspective. Things that you

Read More »
Code example of implementing a firmware upgrade procedure using TSFS snapshot and revert features.

Firmware Update Implementation Using TSFS Snapshots

In the previous article of this series on TSFS snapshots, we have shown how snapshots can be used to design a simple yet robust firmware upgrade procedure. This time, we go from design to implementation, delving into the specifics of the TSFS snapshot management interface. More specifically, we show how we can meet our initial

Read More »
Firmware upgrade procedure block diagram using a snapshot to save the state of the file system prior to beginning the upgrade procedure.

Firmware Upgrade Design Using TSFS Snapshots

This article is the first part of a twofold series on one of the most unique TSFS feature: snapshotting. In this first article, we show how snapshots can ease application development, providing the application designer with an elegant way of handling concurrent read/write accesses. We also introduce a simple firmware update example, to help us

Read More »
Timing diagram of various high-level failures that could break the coherence of a data logging application.

Fail-Safe Design with the TREEspan File System Part 3: Enforcing Coherence Through Transactions

In this article, we show that TSFS transactions go beyond preserving file-level integrity, and can also be used to enforce coherence across multiple files and directories. To support the discussion, we present a real-life application example and demonstrate how a single additional call to tsfs_commit() is all that is needed to make the code immune to unexpected failures.

Read More »
Time diagram of the protection afforded by a transactional file system against various unexpected failure points during a file update.

Fail-Safe Design with the TREEspan File System Part 2: TSFS Transactions

In this second article in this series we see how an application can be designed to withstand such unforeseen events, using TSFS transactions. Doing so, we introduce the tsfs_commit() API. We also discuss the write transaction atomicity property, by which applications can be safely designed ignoring potential partial update issues.

Read More »
Time diagram of various file system unexpected failures and their impact on data and metadata corruption.

Fail-Safe Design with the TREEspan File System Part 1: Introduction

This is the first article of a three-part series on fail-safe, storage-related application design. The first part of the series lays out the fundamental problem of unexpected failures and briefly discusses partial solutions. The second part introduces the TREEspan File System(TSFS) transactions as a means to protect the application against such potentially disruptive events. Finally,

Read More »