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	<title>Data Matters - A blog about flash memory &#187; performance</title>
	<atom:link href="http://blog.datalight.com/tag/performance/feed" rel="self" type="application/rss+xml" />
	<link>http://blog.datalight.com</link>
	<description>Datalight's blog on flash memory, device data storage, data reliability and the embedded industry</description>
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		<title>Press Release: Latest Datalight Flash File System Brings 20 Millisecond Mount Times to Linux through Kernel Versions 2.6.33</title>
		<link>http://blog.datalight.com/20-millisecond-mount-times-to-linux</link>
		<comments>http://blog.datalight.com/20-millisecond-mount-times-to-linux#comments</comments>
		<pubDate>Thu, 06 May 2010 17:02:56 +0000</pubDate>
		<dc:creator>michele</dc:creator>
				<category><![CDATA[Flash File System]]></category>
		<category><![CDATA[Flash Memory Manager]]></category>
		<category><![CDATA[Performance]]></category>
		<category><![CDATA[file system performance]]></category>
		<category><![CDATA[flash file system]]></category>
		<category><![CDATA[linux]]></category>
		<category><![CDATA[performance]]></category>

		<guid isPermaLink="false">http://blog.datalight.com/?p=312</guid>
		<description><![CDATA[Bothell, WA, – May 5, 2010 – Today Datalight announced support for Linux kernel versions up to 2.6.33, the most recently released Linux versions available. FlashFX Tera, the file-system independent flash memory manager and Reliance Nitro, the highly-reliable, high-performance file system offer much faster mount times than UBIFS, YAFFS, or JFFS2. In addition, the Datalight [...]]]></description>
			<content:encoded><![CDATA[<p><strong>Bothell, WA, – May 5, 2010</strong> – Today Datalight announced support for Linux kernel versions up to 2.6.33, the most recently released Linux versions available. FlashFX Tera, the file-system independent flash memory manager and Reliance Nitro, the highly-reliable, high-performance file system offer much faster mount times than UBIFS, YAFFS, or JFFS2. In addition, the Datalight products boost write speed over the standard file systems and provide out-of-the-box support for over 300 different flash memory parts from all the leading suppliers. Linux is finding its way into more devices such as smart phones, automotive infotainment, and industrial equipment which require both responsiveness and 100% data reliability.</p>
<p>“With the growth in adoption of Linux for data-intensive embedded devices, OEMs need a flash file system that better supports their reliability and performance requirements.” said Roy Sherrill, Datalight CEO. “By supporting the most recent kernel versions of Linux we’re filling that gap in the market with a robust, commercial-grade solution backed by our reputation for responsive, high-quality support.”</p>
<p>FlashFX Tera supports the full range of flash technologies including NAND, NOR, and MLC NAND flash in a single driver. Its patented wear-leveling and bad block management extend the useful life of devices using flash. While FlashFX Tera can be used with virtually any file system, pairing it with Reliance Nitro provides an optimized data storage software stack to simplify system development.</p>
<p>FlashFX Tera 1.2 and Reliance Nitro 1.2 are available immediately from Datalight and the Datalight worldwide network of channel partners. Please visit us at <a href="http://www.datalight.com/partners/worldwide-sales-partners" >http://www.datalight.com/partners/worldwide-sales-partners</a> to find a reseller near you.</p>
<p>The Reliance family of <a href="http://www.datalight.com/products/reliance/" >file system</a>s and FlashFX family of <a href="http://www.datalight.com/products/flashfx/" >flash media manager</a>s comprise the Datalight <a href="http://www.datalight.com/products/" ><strong>flash file system</strong></a> solution. Reliance was designed from the ground up for <a href="http://www.datalight.com/products/reliance/" >high reliability</a> applications. Dynamic Transaction Point™ technology gives developers full control over performance and data protection characteristics, protecting users from file system corruption, even after unexpected system interruption. Embedded applications can benefit from faster boot times that remain consistent for the life of the product, regardless of disk size. FlashFX™ Tera features pre-written support for over 300 flash parts, works with virtually any NAND controller, and features <a href="http://www.datalight.com/products/flashfx/" >wear leveling</a>, <a href="http://www.datalight.com/products/flashfx/" >bad block management</a>, and background compaction for unrivaled performance.</p>
<p>For information,  contact:<br />
Kerri McConnell, Director of Marketing<br />
425.686.1069<br />
<a href="mailto:kerri.mcconnell@datalight.com">kerri.mcconnell@datalight.com</a></p>
<h5>About Datalight</h5>
<p>Datalight, Inc. headquartered just north of Seattle, Wash., develops technologies to enable risk-free mobile data. Datalight file system and device driver software ensures reliability, performance and flexibility, and is used worldwide on many of today’s most well-known devices.  For more information, visit <a href="http://www.datalight.com/" >http://www.datalight.com/</a>, call 800.221.6630 or visit blog at <a href="../">http://blog.datalight.com</a><strong> </strong></p>
<p align="center">###</p>
<p align="center">DATALIGHT, Datalight, the Datalight Logo, FlashFX, FlashFX Pro, FlashFX Tera, Reliance, Reliance Nitro, ROM-DOS,  One-Boot, One-Boot+File, and Sockets  are trademarks or registered trademarks of Datalight, Inc. All other product names are trademarks of their respective holders. Specification and price change privileges reserved.<em> </em></p>
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		<title>Reliability on Windows CE 6.0</title>
		<link>http://blog.datalight.com/reliability-on-windows-ce-6-0</link>
		<comments>http://blog.datalight.com/reliability-on-windows-ce-6-0#comments</comments>
		<pubDate>Thu, 01 Oct 2009 21:48:23 +0000</pubDate>
		<dc:creator>michele</dc:creator>
				<category><![CDATA[Flash File System]]></category>
		<category><![CDATA[Performance]]></category>
		<category><![CDATA[Reliability]]></category>
		<category><![CDATA[Beagle Board]]></category>
		<category><![CDATA[file system reliability]]></category>
		<category><![CDATA[flash file system]]></category>
		<category><![CDATA[flash memory performance]]></category>
		<category><![CDATA[performance]]></category>

		<guid isPermaLink="false">http://blog.datalight.com/?p=264</guid>
		<description><![CDATA[Watch Rob Hart demonstrating the Datalight flash file system on the Beagle Board with Windows CE 6.0

 
]]></description>
			<content:encoded><![CDATA[<p>Watch Rob Hart demonstrating the Datalight flash file system on the Beagle Board with Windows CE 6.0</p>
<p><object classid="clsid:d27cdb6e-ae6d-11cf-96b8-444553540000" width="425" height="350" codebase="http://download.macromedia.com/pub/shockwave/cabs/flash/swflash.cab#version=6,0,40,0"><param name="src" value="http://www.youtube.com/v/zyDskPGzMMw" /><embed type="application/x-shockwave-flash" width="425" height="350" src="http://www.youtube.com/v/zyDskPGzMMw"></embed></object></p>
<p><span> </span></p>
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		<title>I HEART Reliance Nitro</title>
		<link>http://blog.datalight.com/i-heart-reliance-nitro</link>
		<comments>http://blog.datalight.com/i-heart-reliance-nitro#comments</comments>
		<pubDate>Mon, 22 Jun 2009 19:51:29 +0000</pubDate>
		<dc:creator>michele</dc:creator>
				<category><![CDATA[Datalight Products]]></category>
		<category><![CDATA[Flash File System]]></category>
		<category><![CDATA[Performance]]></category>
		<category><![CDATA[Reliability]]></category>
		<category><![CDATA[File Systems]]></category>
		<category><![CDATA[flash file system]]></category>
		<category><![CDATA[flash memory performance]]></category>
		<category><![CDATA[performance]]></category>
		<category><![CDATA[reliability]]></category>
		<category><![CDATA[Reliance Nitro]]></category>

		<guid isPermaLink="false">http://blog.datalight.com/i-heart-reliance-nitro</guid>
		<description><![CDATA[With the release of our new file system this week, Reliance Nitro, we asked our Account Managers what they liked most about our new product. Their answers of course included reliability and high performance. Wes Johns and Phillip Allison were so excited they decided to make a video…  watch the youtube video
]]></description>
			<content:encoded><![CDATA[<p>With the <a href="http://www.datalight.com/companyinfo/news.php?newsid=69&amp;newscat=1" >release</a> of our new <a href="http://www.datalight.com/products/reliancenitro/" >file system</a> this week, Reliance Nitro, we asked our Account Managers what they liked most about our new product. Their answers of course included reliability and high performance. Wes Johns and Phillip Allison were so excited they decided to make a video…  <a href="http://www.youtube.com/watch?v=1M60H6bDZJM" onclick="javascript:pageTracker._trackPageview('/www.youtube.com');" target="_blank">watch the youtube video</a></p>
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		<title>Reliance Nitro Demo Video</title>
		<link>http://blog.datalight.com/reliance-nitro-demo-video</link>
		<comments>http://blog.datalight.com/reliance-nitro-demo-video#comments</comments>
		<pubDate>Thu, 21 May 2009 18:04:36 +0000</pubDate>
		<dc:creator>michele</dc:creator>
				<category><![CDATA[Datalight Products]]></category>
		<category><![CDATA[Flash File System]]></category>
		<category><![CDATA[Flash Memory]]></category>
		<category><![CDATA[Performance]]></category>
		<category><![CDATA[Reliability]]></category>
		<category><![CDATA[flash file system]]></category>
		<category><![CDATA[flash memory performance]]></category>
		<category><![CDATA[performance]]></category>
		<category><![CDATA[reliability]]></category>
		<category><![CDATA[reliance]]></category>

		<guid isPermaLink="false">http://blog.datalight.com/reliance-nitro-demo-video</guid>
		<description><![CDATA[We’re totally psyched about Reliance Nitro, our newest file system (yes, we’re file geeks), and we’re always on the lookout for opportunities to show off the performance and reliability attributes it adds to Windows Mobile and Windows CE. When we discovered the relatively-new Beagle Board, it occurred to us that a small, low-cost platform might [...]]]></description>
			<content:encoded><![CDATA[<p>We’re totally psyched about Reliance Nitro, our newest file system (yes, we’re file geeks), and we’re always on the lookout for opportunities to show off the <a href="http://www.datalight.com/companyinfo/news.php?newsid=65" >performance</a> and reliability attributes it adds to Windows Mobile and Windows CE. When we discovered the relatively-new Beagle Board, it occurred to us that a small, low-cost platform might be just the thing to demonstrate Nitro’s amazing benefits. As you’ve probably heard, the Beagle is making waves with its low cost (around $150) and diminutive size. It uses an OMAP 3530 processor and 256MB of NAND. Though they are most commonly used with Linux, we lucked out in having a partner (MPC Data) who has already developed a Windows CE BSP for it. After a few phone calls, the wizards at MPC Data were able to develop a slick video playback demo app, and presto, the Reliance Nitro Beagle Demo was born! Amateur videographers that we are (ok, REALLY amateur), we recently videotaped John Burnham, who has been working on this project on the Datalight side (and who is a really good sport, btw) showing what happens when power is interrupted during a file write and the extra reliability factor of Reliance Nitro on Windows CE. Be sure to check it out <a href="http://www.youtube.com/watch?v=LGOBm3PsS1A" onclick="javascript:pageTracker._trackPageview('/www.youtube.com');">here</a>.</p>
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		<title>File System Tuning using Dynamic Transaction Point Technology</title>
		<link>http://blog.datalight.com/file-system-tuning-using-dynamic-transaction-point-technology</link>
		<comments>http://blog.datalight.com/file-system-tuning-using-dynamic-transaction-point-technology#comments</comments>
		<pubDate>Wed, 25 Mar 2009 20:27:45 +0000</pubDate>
		<dc:creator>michele</dc:creator>
				<category><![CDATA[Flash File System]]></category>
		<category><![CDATA[file system tuning]]></category>
		<category><![CDATA[flash file system]]></category>
		<category><![CDATA[flash memory performance]]></category>
		<category><![CDATA[performance]]></category>
		<category><![CDATA[reliance]]></category>

		<guid isPermaLink="false">http://blog.datalight.com/?p=85</guid>
		<description><![CDATA[Datalight Reliance includes unique technology called Dynamic Transaction Point ™ which provides the flexibility and control device manufacturers need to tune the performance of their device. It enables multiple configurations that can run simultaneously to provide scenario-specific performance optimization. To highlight this technology, we have added a section to Datalight&#8217;s website to describe some common [...]]]></description>
			<content:encoded><![CDATA[<p>Datalight Reliance includes unique technology called Dynamic Transaction Point ™ which provides the flexibility and control device manufacturers need to tune the performance of their device. It enables multiple configurations that can run simultaneously to provide scenario-specific performance optimization. To highlight this technology, we have added a section to Datalight&#8217;s website to describe some common embedded devices and the corresponding file system tuning attributes for each of them</p>
<p><a href="http://www.datalight.com/filesystemtuning" >www.datalight.com/filesystemtuning</a></p>
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		<title>Datalight Cuts Boot Time in Half for New LG Navigator</title>
		<link>http://blog.datalight.com/datalight-cuts-boot-time-in-half-for-new-lg-navigator</link>
		<comments>http://blog.datalight.com/datalight-cuts-boot-time-in-half-for-new-lg-navigator#comments</comments>
		<pubDate>Thu, 06 Nov 2008 21:36:05 +0000</pubDate>
		<dc:creator>RobHart</dc:creator>
				<category><![CDATA[Consumer Other]]></category>
		<category><![CDATA[Cost Savings]]></category>
		<category><![CDATA[Flash Memory Manager]]></category>
		<category><![CDATA[Performance]]></category>
		<category><![CDATA[bad block management]]></category>
		<category><![CDATA[flash manager]]></category>
		<category><![CDATA[GPS]]></category>
		<category><![CDATA[NAND]]></category>
		<category><![CDATA[performance]]></category>
		<category><![CDATA[Windows CE]]></category>

		<guid isPermaLink="false">http://blog.datalight.com/datalight-cuts-boot-time-in-half-for-new-lg-navigator</guid>
		<description><![CDATA[The Challenge
Recently, LG Electronics, a well-known Korean-based manufacturer of consumer electronics, created a multimedia-enabled portable navigator for the North American market. The LN790 features a 4.3” LCD screen, Bluetooth hands-free functionality, and video-enabled playback. Ruggedness and fast access to data are important to consumers in this market, so the device was designed to boot directly [...]]]></description>
			<content:encoded><![CDATA[<p><strong>The Challenge</strong><br />
Recently, LG Electronics, a well-known Korean-based manufacturer of consumer electronics, created a multimedia-enabled portable navigator for the North American market. The LN790 features a 4.3” LCD screen, Bluetooth hands-free functionality, and video-enabled playback. Ruggedness and fast access to data are important to consumers in this market, so the device was designed to boot directly from a NAND mass storage environment using Windows CE. Unfortunately, LG product engineers had a difficult time getting the device to boot fast enough using CE’s FAL/FMD flash drivers.  At just over two minutes, the startup time did not match LG’s reputation for high-performance consumer devices.</p>
<p><strong>The Datalight Solution</strong><br />
As LG engineers went searching for solutions to the boot speed problem, they discovered that Datalight FlashFX® Pro uses a more efficient approach to managing bad blocks than CE’s standard FMD/FAL drivers, which can speed boot time significantly.  This difference is especially apparent when the device is using a large NAND disk, because boot time is somewhat proportional to the size of the flash.<br />
Why is FlashFX Pro more efficient? Startup with FAL requires the driver to read more data as part of its mount sequence, a lengthy process particularly if the disk is large. In contrast, FlashFX Pro requires a much simpler check of the media to complete the initial mount.</p>
<p><strong>The Customer Payoff</strong><br />
After implementation of FlashFX Pro, LG engineers were delighted to discover that the device’s boot time was cut by more than half. By using FlashFX Pro instead of the native Windows CE drivers, LG designers were able to achieve the performance their customers expect from a premium-quality personal navigator.  There was also an additional benefit they hadn’t counted on – FlashFX Pro support for over 200 flash parts means that the LN790 will be future-proof from flash parts going on allocation, unexpected price fluctuations, and end-of-life issues.</p>
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		<title>Datalight Flash File System Boosts Performance for Devices Built with MontaVista Linux</title>
		<link>http://blog.datalight.com/datalight-flash-file-system-boosts-performance-for-devices-built-with-montavista-linux</link>
		<comments>http://blog.datalight.com/datalight-flash-file-system-boosts-performance-for-devices-built-with-montavista-linux#comments</comments>
		<pubDate>Tue, 12 Aug 2008 04:35:16 +0000</pubDate>
		<dc:creator>michele</dc:creator>
				<category><![CDATA[Datalight Products]]></category>
		<category><![CDATA[Flash Industry Info]]></category>
		<category><![CDATA[Add new tag]]></category>
		<category><![CDATA[flash file system]]></category>
		<category><![CDATA[flash memory performance]]></category>
		<category><![CDATA[linux]]></category>
		<category><![CDATA[performance]]></category>

		<guid isPermaLink="false">http://blog.datalight.com/datalight-flash-file-system-boosts-performance-for-devices-built-with-montavista-linux</guid>
		<description><![CDATA[Bothell, Wash., – August 12, 2008 – Datalight announced today that it has released new versions of Reliance™ and FlashFX® Pro, with pre-configured support for  MontaVista® Linux®. The new install experience includes simplified integration within MontaVista DevRocket, an Eclipse-based IDE that streamlines common embedded  development tasks. Dropped into DevRocket, Datalight products build as kernel loadable [...]]]></description>
			<content:encoded><![CDATA[<p>Bothell, Wash., – August 12, 2008 – Datalight announced today that it has released new versions of Reliance™ and FlashFX® Pro, with pre-configured support for  MontaVista® Linux®. The new install experience includes simplified integration within MontaVista DevRocket, an Eclipse-based IDE that streamlines common embedded  <strong>development</strong> tasks. Dropped into <strong>DevRocket</strong>, Datalight products build as kernel loadable modules that work with a project’s OS image. Sample bootstrap code is also  supplied for developers who need to integrate the products into a boot loader.</p>
<p>&#8220;Developers choose MontaVista Linux for faster time-to-market, integration, and stable, fully tested code. We are pleased that Datalight has extended these benefits at  the flash memory file system level, and to provide embedded Linux developers with added performance and reliability,” said Dan Cauchy, Senior Director of Market Development, MontaVista Software.</p>
<p>Other upgrades include a read-only version of Reliance inside the Datalight Loader. This small footprint version permits a bootloader to load an OS image directly from a reliance partition. Devices benefit from risk-free “in-place OS upgrades” enabled by the application-controlled transaction point feature of Reliance. The new versions also feature enhancements in reliability, as well as support for a wide range of new flash parts. FlashFX Pro now supports Spansion NS-P, Samsung FlexOneNAND, Micron 55nm flash parts, and all CFI-compliant NOR parts. The Datalight flash file system solution is comprised of the Reliance file system and FlashFX Pro intelligent flash media manager. Reliance was designed from the ground up for high reliability applications. Dynamic Transaction Point™ technology provides 100% immunity from file corruption, even after unexpected system interruption. Embedded applications can benefit from faster boot times that remain consistent for the life of the product, regardless of disk size.</p>
<p>FlashFX Pro features pre-written support for over 200 flash parts, works with virtually any NAND controller, and features wear leveling, bad block management, and garbage compaction for unrivaled performance. Datalight flash file system products are also available on other operating systems and integrated development environments.</p>
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		<title>Choosing NAND or NOR Flash Memory: Tradeoffs and Strategies</title>
		<link>http://blog.datalight.com/choosing-nand-or-nor-flash-memory-tradeoffs-and-strategies</link>
		<comments>http://blog.datalight.com/choosing-nand-or-nor-flash-memory-tradeoffs-and-strategies#comments</comments>
		<pubDate>Tue, 08 Jul 2008 20:53:09 +0000</pubDate>
		<dc:creator>michele</dc:creator>
				<category><![CDATA[Cost Savings]]></category>
		<category><![CDATA[Extended Flash Life]]></category>
		<category><![CDATA[Flash Memory]]></category>
		<category><![CDATA[Flash Memory Manager]]></category>
		<category><![CDATA[Performance]]></category>
		<category><![CDATA[Reliability]]></category>
		<category><![CDATA[bad block management]]></category>
		<category><![CDATA[flash manager]]></category>
		<category><![CDATA[NAND]]></category>
		<category><![CDATA[performance]]></category>
		<category><![CDATA[reliability]]></category>

		<guid isPermaLink="false">http://blog.datalight.com/?p=30</guid>
		<description><![CDATA[Consumer electronics and embedded software devices are using larger amounts of flash memory for nonvolatile storage than ever before. So what kind of flash memory should you use? The choice between using NAND and NOR Flash may not be a simple one for the complex embedded devices being developed today. While ever-larger media files are [...]]]></description>
			<content:encoded><![CDATA[<p>Consumer electronics and embedded software devices are using larger amounts of flash memory for nonvolatile storage than ever before. So what kind of flash memory should you use? The choice between using NAND and NOR Flash may not be a simple one for the complex <a class="zem_slink" title="Embedded system" rel="wikipedia" href="http://en.wikipedia.org/wiki/Embedded_system" onclick="javascript:pageTracker._trackPageview('/en.wikipedia.org');">embedded devices</a> being developed today. While ever-larger media files are driving increased demand for inexpensive NAND, powerful new operating systems and intricate applications running on fast processors ask for the fast-executing code NOR can support.</p>
<p>Read Datalight whitepaper <em>Choosing NAND or NOR <a class="zem_slink" title="Flash memory" rel="wikipedia" href="http://en.wikipedia.org/wiki/Flash_memory" onclick="javascript:pageTracker._trackPageview('/en.wikipedia.org');">Flash Memory</a>: Tradeoffs and Strategies to Learn More</em></p>
<p>Consumer electronics and embedded software devices are using larger amounts of flash memory for nonvolatile storage than ever before. One important decision in designing such devices is what kind of flash memory to use: NAND or NOR?</p>
<p>NOR flash memory has traditionally been used to store relatively small amounts of executable code for embedded computing devices such as PDAs and cell phones. NOR is well suited to use for code storage because of its reliability, fast read operations, and random access capabilities. Because code can be directly executed in place, NOR is ideal for storing firmware, boot code, operating systems, and other data that changes infrequently.</p>
<p>NAND flash memory has become the preferred format for storing larger quantities of data on devices such as USB Flash drives, digital cameras and MP3 players. Higher density, lower cost, and faster write and erase times, and a longer re-write life expectancy make NAND especially well suited for consumer media applications in which large files of sequential data need to be loaded into memory quickly and replaced with new files repeatedly.</p>
<p>The choice between using NAND and NOR Flash may not be a simple one for the complex embedded devices being developed today. While ever-larger media files are driving increased demand for inexpensive NAND, powerful new operating systems and intricate applications running on fast processors call for the kind of fast-executing code NOR can support. An important example is a smart phone or PDA that combines a tremendous need for storage with a demanding set of application performance requirements. In some cases an optimal design might call for both types of flash memory in the same device.</p>
<p>Whichever type of flash is used in a device, there are certain negative performance characteristics that need to be mitigated. NOR is fast to read current data but markedly slower to erase it and write new data. NAND is fast to erase and write, but slow to read non-sequential data through its serial interface. NAND is also prone to single-bit errors, requiring rigorous algorithms for <a class="zem_slink" title="Error detection and correction" rel="wikipedia" href="http://en.wikipedia.org/wiki/Error_detection_and_correction" onclick="javascript:pageTracker._trackPageview('/en.wikipedia.org');">error detection and correction</a>.</p>
<p>Well-designed software strategies can be very effective in increasing the performance and reliability of Flash hardware. The goals of flash memory management software include:</p>
<p><strong>Avoid loss of data. </strong>Perhaps the most important goal in managing flash memory is to assure that no data is ever lost as a result of an interrupted operation or the failure of a memory block. <strong> </strong>There are several ways that flash management software can achieve this goal. Rewrite operations, for example, can be managed in such a way that new data is written and verified before the old data is deleted, so that no power loss or other interruption can result in the loss of both old and new data. Bad block management is another important safeguard to prevent data being written to memory blocks that have failed. Software can check for bad blocks shipped from the factory, as is typical with NAND, and avoid writing to those blocks from the beginning. When blocks go bad over time they can be identified and managed so that they are no longer used. Finally, as the end of media life nears, good memory management software can implement a graceful strategy such as placing the entire flash unit in a read-only state, thereby avoiding data loss when the number of block errors exceeds a predefined number.</p>
<p><strong> </strong></p>
<p><strong>Improve effective performance. </strong>Two ways media management software can improve performance are background compaction and multithreading. Compaction reclaims space by identifying blocks that have obsolete data that can be erased, copying any valid data to a new location, then erasing the blocks to make them available for reuse. Such compaction increases the amount of usable space on the media and improves write performance. Compaction may also help to defragment noncontiguous data for improved performance on read operations. The space recovery is particularly valuable for the more costly NOR memory and the defragmentation benefits the slower-reading NAND. Compaction is best performed in the background during idle time, however, or it can interfere with critical operations and degrade performance. This is where a multithreading system becomes important. By allowing high-priority read requests to interrupt low-priority maintenance operations, a multithreading system can reduce read latency by orders of magnitude compared to a single-thread solution.</p>
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<p><strong>Maximize media lifespan. </strong>When some blocks of memory contain fixed content, such as binary code, the remaining blocks will experience increased demand for erase and write operations, leading to earlier failure. Wear-leveling algorithms can prevent overuse of memory blocks and prevent a “stalemate” scenario in which a small region of memory becomes locked in a pattern of repeated writing and compaction. Wear leveling software can monitor block usage to identify high-use areas and low-use areas containing static data, then swap the static data into the high use areas. It can also balance write operations across all available blocks by choosing the optimal location for each write operation.</p>
<p>The decision between NAND and NOR memory will ultimately depend on both technical and pricing requirements of the device being built. Whatever type or combination of flash is used, it is prudent to include memory management software to prevent data loss while improving the performance and maximizing the lifespan of the memory.</p>
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