New file system constrains Treo 650 storage capacity

The change to flash memory from DRAM (dynamic RAM) for PalmOne Inc.'s new Treo 650 smart phone appears to have had the unintended consequence of reducing the amount of memory that is actually available to users. As a result, PalmOne plans to offer a free 128M-byte expansion card to Treo 650 purchasers to get around the problem, the company said Monday.

Small files, such as contacts or tasks, must now be stored in chunks that are much larger than the actual files themselves. This means that the same files a user stored on a Treo 600 might not all fit on the Treo 650. The Treo 650 was released to the public last week through Sprint Corp. and PalmOne's Web site.

A PalmOne spokeswoman confirmed the memory issue in a statement last week. The capacity problem is a design tradeoff caused by the decision to use a new file system that allows users to quickly change batteries and protect their data when power runs out, she said. Treo enthusiast Web sites such as MyTreo.net were the first to highlight the problem.

As a general rule of thumb, users thinking about upgrading to the Treo 650 should understand that their old data will require 33 percent more storage capacity on the new smart phone, PalmOne warned users in an online support posting.

On the latest version of the popular Treo smart phone, PalmOne made two important changes to the system's design. The device now uses flash memory, rather than DRAM, to store data. Flash memory is nonvolatile, which means it can store data without a constant supply of electricity and protect that data in the event of a battery failure or unintended shutdown. PalmOne users have clamored for flash memory for years, and were finally accommodated with the release of the Tungsten T5 and Treo 650.

In order to use flash memory, PalmOne had to switch the file system technology that decides how files are stored. The Treo 650 now uses the NVFS (nonvolatile flash system) file system to store data in clusters. This file system is based on FAT (file allocation table) technology, which was the underlying file system technology for Microsoft Corp.'s DOS operating system as well as Windows 95 and Windows 98. The Windows NT and XP operating systems use a different technology.

In the Treo 650, NVFS technology stores data in 512-byte blocks. This means that even small 20-byte files, such as a contact's phone number, are stored in 512-byte blocks. Smaller files stored in DRAM on older smart phones and handhelds took up only as much space as the size of the file.

This is inefficient, but FAT-based file systems were designed for PCs that work with larger file sizes and have disk drives in the gigabyte range.

However, the Treo 650 only comes with 23M bytes of user accessible flash memory. This is actually slightly less capacity than the Treo 600, which used 24M bytes of volatile DRAM to store information. Users are further constrained by the 5M bytes of storage required for the Documents To Go application, which allows Palm OS users to view and edit Microsoft Corp.'s Office files.

Therefore, a user who wishes to transfer files from an older Palm device to the new Treo 650 might not be able to fit all of their application or data onto the new system, the PalmOne spokeswoman said. A typical address book would take up an additional 800K bytes of storage space on the Treo 650, the company said in an online support forum.

Third-party applications should not be affected in the same manner as contacts and calendar data, but users should check with their application provider to be sure, according to PalmOne's online support page. That Web page can be found at http://kb.palmone.com/SRVS/CGI-BIN/WEBCGI.EXE/,/?St=762,E=0000000000098961520,K=2985,Sxi=7,useTemplate=Case.tem,CASE=35222.

PalmOne believes that the issue will affect only a small percentage of users who have filled their Treo 600 units with data, the spokeswoman said. However, the company will offer a free 128M-byte SD (Secure Digital) expansion card to any purchaser of a Treo 650 who requests the card, she said. Users should check PalmOne's support pages starting in early December for details about the free offer. A 128M-byte SD card costs around US$15 at retail.

If a user of a Palm OS device has filled 16M bytes or more of storage, they should consider offloading some data to the expansion card if upgrading to a Treo 650, according to PalmOne's support pages.

The company plans to release a ROM upgrade that will improve the efficiency of its flash memory, the spokeswoman said. It will also post information on its support site about the issue.

While the NVFS memory problem will not affect most Treo 650 users, it's somewhat embarrassing for PalmOne's flagship product to ship with this type of issue, said Sam Bhavnani, an analyst with Current Analysis Inc. in La Jolla, California.

"It's surprising this wasn't uncovered internally before. It might be one of those things where they needed to hit a launch date" in order to have the product out in time for holiday shoppers, he said.

PalmOne's decision to use the NVFS file system could signal that it plans to eventually incorporate an iPod-like hard disk drive into the Treo product, said Will Strauss, principal analyst with Forward Concepts Co. in Tempe, Arizona.

The Treo 650 has a more powerful processor than its predecessor that allows the smart phone to handle more complex video encoding and decoding. The new XScale chip from Intel Corp., coupled with a higher resolution screen, could mean that PalmOne is preparing to launch a video-enabled Treo in the near future, Strauss said. Any video handheld would require enough storage as to make a flash memory storage design impractical, he said.

PalmOne declined to comment about future plans for the Treo family.

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