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4GB Flash Voyager CMFUSB2.0-4GB slow to write : solution!


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Based on a stopwatch and a 625 MB avi file,


Drive formated FAT32


Time to read from flash disk to HDD : 45 seconds (transfer speed 14 MB/s)

Time to write to flash disk from HDD : 7 minutes (transfer speed 1.5 MB/s)


I kid you not. No security software installed, either. Windows optimised the drive for performance. (I'm using Vista Beta 2)


Drive formatted NTFS (default allocation size)


Time to read from flash disk to HDD : 40 seconds (transfer speed 16 MB/s)

Time to write to flash disk from HDD : 70 seconds (transfer speed 9 MB/s)


So Im guessing that the spate of posts on this board about slow write times are people who formatted FAT32. (T/F Comments?)




The specs of the drive do not imply that the transfer speeds require NTFS. Further, Vista still claims the drive isnt fast enough to use ReadyBoost, which was the main reason I got the thing in the first place.


I will see how it performs on a couple of other PCs tomorrow.

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The ReadyBOOST feature of Vista uses performance at a 4K block read/write. It requires 4 MB's at that specific block size. The Flash Voyager does not meet that requirement. It is interesting that NTFS is that much faster than FAT32 the Flash Voyager. Thanks for the info.
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Same test as before, straight transfer of a large file, this time in FAT32 only:




625 MB .avi file (6.56E+08 bytes)


*format flash disk FAT32*

read: Copy file to computer from flash disk

*reformat flash disk FAT32*

write: copy file from computer back to flash disk.


measured transfer times:


Pentium M notebook (XP pro SP2) FAT32

read: 43s (15MB/s)

write: 70s (9MB/s)


Sempron s754 desktop (w2k SP4) FAT32

read: 35s (18MB/s)

write: 68s (9MB/s)


The drive is hitting the specified read/write performance without issue in both XP and W2k, even formatted FAT32.


The problem is related to either the hardware of my home system (Athlon 64 / nForce 3 150) or the Vista beta 2 operating system.


The very slow access time of the Voyager (20ms I read somewhere, 10-20x higher than other drives) may be a contributing factor, though... if Vista is trying to copy the file through a series of small, random blocks rather than sequencially for some reason.


To test this I will try my other fast USB memory (Elecom 256MB, 18MB write/25Mb read) and see if is slow or not.


P.S. Readyboost performance requirements: 2.5MB/sec throughput for 4K random reads and 1.75MB/sec throughput for 512K random writes. Pity the Voyager doesnt cut it. Any particular reason why not or is the drive just based on an older technology?

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My Elecom flash drive has the same problem.


On a Pentium 630 system running XP, the time to move 3x33MB files was


Elecom: read 4s (25 MB/s), write 8s (13 MB/s)

Corsair: read 5.5s (18 MB/s), write 10s (10 MB/s)


Meanwhile in my Athlon64/nForce3 150 running Vista


Elecom: read 6s (17 MB/s), write 20s (5 MB/s)

Corsair: read 7.5s (13 MB/s), write 25s (4 MB/s)


The drop in speed isn't as drastic as it was with the 625 MB avi since the first 100 MB is relatively fast. Larger files or groups of files experience a more severe write bottleneck.


So Im guessing the Vista drivers for nForce3 are giving me this problem.

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We have a similar problem, booting from the 4gb voyager, either FAT or FAT32, no security partition, ghosting to a workstation with a 1.7gb ghost file. Takes 68 minutes !!!!! Even tried booting from floppy then using the voyager same result.


This is a HP 7600 has latest business bios which support USB 2.0 natively. Tried numerous switches in ghost, same again. Takes 59 minutes to write an image back.

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If you boot from the voyager or a floppy disk its slow at reading and writing. Also when you in DOS and you DIR, the usb drive hangs for a couple of minutes and is flashing away then returns the command prompt then on after will do a DIR with no problems until you reboot.


If you are in XP or 2000 the drive seems to be alot quicker, so I dunno if windows is emulating something im not sure. I have even tried the panasonic usb2 drivers in dos to try and speed it up.


I think to get this much trouble from the device, there must be design problems, which seem to be reluctantly addressed. Or addressed in a way that steers blame from the manufacturer. I guess we will be seeing a revised product.

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The whole point of the public beta release is to find these sorts of issues. So, no, testing on Vista is not useless, far from it.


Its not exactly the best platform for confirming if a flash drive is working or not, on that we can agree. Since I've already confirmed my drive is working, this is no longer an issue. I want to get to the bottom of why it doesn work on my home PC...


I think it has something to do with certain USB flash memory having a fast sequential write time but a very slow random write time. This isnt a problem normally, except that with either the Vista USB driver and/or my hardware large files are not written in sequencial blocks as the should be but get spilt up into smaller bits and written randomly. (Thought: I wonder if Vista implements its own wear levelling algorithm automatically on flash memory?)


As an aside to zircom, the Voyager will also perform poorly when writing a large number of very small files regardless of OS. If the ghost image was being written in small steps, this would be the explanation for your slow write times under DOS.


The Voyager in particular (and my Elecom to a lesser extent) has rather appalling performance compared to the competition when the file size drops below 64kB. At >=64kB, however, they are both excellent.


Sandra 2007 removable storage benchmark for my Voyager 4GB on IBM x31 laptop:


512B Files Test

Read Performance : 28294 operation(s)/min (1886 kB/sec, 12x)

Write Performance : 335 operation(s)/min (22 kB/sec, 0x)


*** edit: would someone please explain why I can write 970 32kB files per minute but only 335 0.5kB files? ***


32kB Files Test

Read Performance : 14061 operation(s)/min (7499 kB/sec, 49x)

Write Performance : 970 operation(s)/min (517 kB/sec, 3x)


256kB Files Test

Read Performance : 3456 operation(s)/min (14746 kB/sec, 98x)

Write Performance : 740 operation(s)/min (3157 kB/sec, 21x)


2MB Files Test

Read Performance : 489 operation(s)/min (16691 kB/sec, 111x)

Write Performance : 119 operation(s)/min (4062 kB/sec, 27x)


64MB Files Test

Read Performance : 15 operation(s)/min (16384 kB/sec, 109x)

Write Performance : 8 operation(s)/min (8738 kB/sec, 58x)


Running the ATTO benchmark gives the full rated transfer speeds on any file size above 128kB, but its qualitatively otherwise the same story.


Since I dont have any other machine running Vista, can someone please test their Voyager on Vista and report the time for writing a large file?

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  • 2 weeks later...

Dual boot XP and Vista on a P4 3.4GHz Notebook with SATA drive and Promise 378 controller (both XP and Vista using the exact same 32bit Promise controller driver):


Flash Voyager USB2.0 1GB formatted as indicated:


XP sp2 Home, 930MB avi file:

Flash FAT32 format write: 107sec, read: 52sec

Vista Beta 2 updated, same file:

Flash FAT format write: 13.5min, read: 62sec

Flash FAT32 format write: 15min, read: 46sec

Flash NTFS format write: 102sec, read: 47sec


Vista is obviously having problems with FAT filesystems.


Sandra benchmarks for the flash drive in XP listed here for reference:


Note the same discrepency at the 512B file size.


Personally I think the reason Readyboost rejects the Flash Voyager drive is the extraordinarily high random access time. Haven't been able to benchmark random transfer rates though, so can't say for sure.

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Thanks for confirming the slow write times on Vista/FAT. Its nice to learn its not just me.


I concur that a drive with faster random access times, preferably sub-millisecond, is going to be needed for FAT file writes under Vista and getting Readyboost to work


The performance specified by Microsoft is:


2.5MB/sec throughput for 4K random reads

1.75MB/sec throughput for 512K random writes


(I assume thats a typo and it was meant to read 4kB and 512Bytes)


If you believe Sandra, the Corsair's write performance at 512B is 22kB/s. Off by... ooh.. a factor of 100...


Judging by the THG review (a little dated now) there is a clear distintion when it comes to random access times over different models and brands. Either its in the range of 20-50 ms, or 0.5-1 ms. My guess is that Vista will only play nice with the latter. The Corsair unfortunately sits squarely in the former category.




Note this review incorrectly shows the write speed of the 2GB Corsair as 13MB/s rather than 9MB/s. At best they copied the 1GB results. At worst they made everything up. Take with a grain of salt.


I would like to get my hands on some ReadyBoost capable flash, but I dont want to buy any more USB drives before I have some guarentee they will work.

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Judging by the THG review (a little dated now) there is a clear distintion when it comes to random access times over different models and brands. Either its in the range of 20-50 ms, or 0.5-1 ms.


And sometimes both within a singal device? I just ran an HD Tune benchmark on my 1GB Flash Voyager. The graphic that the results were plotted on shows that the majority of access attempts were made at 37ms. However, there were a significant number of accesses that were made at 1ms! The overall average reported was 27ms, but all of the values were either 1ms or 37ms.

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  • 3 weeks later...

Heh, that's strange, though I have heard that certain "parts" of the flash memory can be more quickly accessed than others. Just having a few fast blocks wont satisfy Vista though.


Meanwhile I got a Sandisk Ultra II Plus SD card, the one with the flip up USB connector built in. I discovered this can be enabled to use ReadyBoost through the USB connector, even if my multi-card reader isnt fast enough use it directly through the SD interface.


The Ultra II (at least the genuine ones) show a clean 10MB/s read 10MB/s write, with a gentle falloff as the file size decreases. Although the Voyager still out-reads it by almost 2x on large files, the Ultra II must be credited for having a solid all-round performance.


As a final word on my 4GB Voyager: Its great to use, fast and convenient with more than enough capacity. I can live with not being able to use it with Readyboost. My main concern I would like to telegraph to Corsair is the issue of the Vista USB drivers. It does look like Microsoft has built in a wear-levelling algorithm into the driver that absolutely kills FAT write performance for flash drives with high access times... you guys should have a chat with them about some sort of conditional line "if access time > 20 ms then wear_levelling=0 (disabled)" getting added to the driver code before Vista goes retail if you still plan on selling the Voyager after 2006.

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