write rate slows as large CF card fills?

Question. Has anyone observed a slowdown in the write rate
of images to a large compact flash card when the card gets
close to full with a large number of images? I have several
2 GB Lexar 40x and 2 GB Sandisk Ultra II cards and when writing
highest quality jpegs on a ID Mark II I see no problems
with write speed, even up to the last image.
But I also have a 4GB Lexar 40x card,
and as it fills, say starting around 900 images (~75% full),
the write speed slows way down. I haven't noticed that same
problem with Raws, but then I usually swap the card out at
about 75% full. Has anyone else seen this?

Roger

"Roger N. Clark (change username to rnclark)" wrote in
message ...
Question. Has anyone observed a slowdown in the write rate
of images to a large compact flash card when the card gets
close to full with a large number of images? I have several
2 GB Lexar 40x and 2 GB Sandisk Ultra II cards and when writing
highest quality jpegs on a ID Mark II I see no problems
with write speed, even up to the last image.
But I also have a 4GB Lexar 40x card,
and as it fills, say starting around 900 images (~75% full),
the write speed slows way down. I haven't noticed that same
problem with Raws, but then I usually swap the card out at
about 75% full. Has anyone else seen this?

Roger

I don't know, but I will say that I have noticed that **playback** of images
slows with a full card vs. a mostly empty card (microdrive).

Do you format the card each time, or just delete?
Are you deleting files here and there as you go?
These things could be causing fragmentation.
I know that you might not be using a hard drive (microdrive), but it is my
impression that even with solid state memory, the controller still has to
organize the space on it similarly to a hard drive. As the drive fills, it
may be jumping around looking for blocks to partially fill... I don't know
for sure, and someone more in-the-know may pounce on me with a nasty
correction...but this makes sense to me.

The part that does NOT make sense is that one image format over another
would be more problematic than another (assuming the storage space required
is similar).

"Roger N. Clark (change username to rnclark)" wrote in
message ...
Question. Has anyone observed a slowdown in the write rate
of images to a large compact flash card when the card gets
close to full with a large number of images? I have several
2 GB Lexar 40x and 2 GB Sandisk Ultra II cards and when writing
highest quality jpegs on a ID Mark II I see no problems
with write speed, even up to the last image.
But I also have a 4GB Lexar 40x card,
and as it fills, say starting around 900 images (~75% full),
the write speed slows way down. I haven't noticed that same
problem with Raws, but then I usually swap the card out at
about 75% full. Has anyone else seen this?

Roger

I don't know, but I will say that I have noticed that **playback** of images
slows with a full card vs. a mostly empty card (microdrive).

Do you format the card each time, or just delete?
Are you deleting files here and there as you go?
These things could be causing fragmentation.
I know that you might not be using a hard drive (microdrive), but it is my
impression that even with solid state memory, the controller still has to
organize the space on it similarly to a hard drive. As the drive fills, it
may be jumping around looking for blocks to partially fill... I don't know
for sure, and someone more in-the-know may pounce on me with a nasty
correction...but this makes sense to me.

The part that does NOT make sense is that one image format over another
would be more problematic than another (assuming the storage space required
is similar).

Roger N. Clark (change username to rnclark) wrote:
Question. Has anyone observed a slowdown in the write rate
of images to a large compact flash card when the card gets
close to full with a large number of images? I have several
2 GB Lexar 40x and 2 GB Sandisk Ultra II cards and when writing
highest quality jpegs on a ID Mark II I see no problems
with write speed, even up to the last image.
But I also have a 4GB Lexar 40x card,
and as it fills, say starting around 900 images (~75% full),
the write speed slows way down. I haven't noticed that same
problem with Raws, but then I usually swap the card out at
about 75% full. Has anyone else seen this?

Roger

Yes, I reported this many threads ago, based on using a Nikon Coolpix 990
with about 400+ images per 128MB card.

My conclusion was that the problem was most likely due the the number of
files in a directory, and using the FAT rather than the NTFS file system.
The newer Nikon cameras limit the number of files in a single directory to
200 (I think) and the slowdown is reduced or eliminated.

As you have a 4GB card, it could be a FAT32 versus FAT16 issue, with the
camera's firmware perhaps not supporting FAT32 quite as well as FAT16?

Cheers,
David

Roger N. Clark (change username to rnclark) wrote:
Question. Has anyone observed a slowdown in the write rate
of images to a large compact flash card when the card gets
close to full with a large number of images? I have several
2 GB Lexar 40x and 2 GB Sandisk Ultra II cards and when writing
highest quality jpegs on a ID Mark II I see no problems
with write speed, even up to the last image.
But I also have a 4GB Lexar 40x card,
and as it fills, say starting around 900 images (~75% full),
the write speed slows way down. I haven't noticed that same
problem with Raws, but then I usually swap the card out at
about 75% full. Has anyone else seen this?

Roger

Yes, I reported this many threads ago, based on using a Nikon Coolpix 990
with about 400+ images per 128MB card.

My conclusion was that the problem was most likely due the the number of
files in a directory, and using the FAT rather than the NTFS file system.
The newer Nikon cameras limit the number of files in a single directory to
200 (I think) and the slowdown is reduced or eliminated.

As you have a 4GB card, it could be a FAT32 versus FAT16 issue, with the
camera's firmware perhaps not supporting FAT32 quite as well as FAT16?

Cheers,
David

Mark² wrote:
"Roger N. Clark (change username to rnclark)" wrote in
message ...

Question. Has anyone observed a slowdown in the write rate
of images to a large compact flash card when the card gets
close to full with a large number of images? I have several
2 GB Lexar 40x and 2 GB Sandisk Ultra II cards and when writing
highest quality jpegs on a ID Mark II I see no problems
with write speed, even up to the last image.
But I also have a 4GB Lexar 40x card,
and as it fills, say starting around 900 images (~75% full),
the write speed slows way down. I haven't noticed that same
problem with Raws, but then I usually swap the card out at
about 75% full. Has anyone else seen this?

Roger


I don't know, but I will say that I have noticed that **playback** of images
slows with a full card vs. a mostly empty card (microdrive).

Do you format the card each time, or just delete?

I format opften, but occasionally delete all. On the 4GB card, I have
only formatted, as it is much faster.

Are you deleting files here and there as you go?
Never.

These things could be causing fragmentation.
I know that you might not be using a hard drive (microdrive), but it is my
impression that even with solid state memory, the controller still has to
organize the space on it similarly to a hard drive. As the drive fills, it
may be jumping around looking for blocks to partially fill... I don't know
for sure, and someone more in-the-know may pounce on me with a nasty
correction...but this makes sense to me.

The part that does NOT make sense is that one image format over another
would be more problematic than another (assuming the storage space required
is similar).

Mark² wrote:
"Roger N. Clark (change username to rnclark)" wrote in
message ...

Question. Has anyone observed a slowdown in the write rate
of images to a large compact flash card when the card gets
close to full with a large number of images? I have several
2 GB Lexar 40x and 2 GB Sandisk Ultra II cards and when writing
highest quality jpegs on a ID Mark II I see no problems
with write speed, even up to the last image.
But I also have a 4GB Lexar 40x card,
and as it fills, say starting around 900 images (~75% full),
the write speed slows way down. I haven't noticed that same
problem with Raws, but then I usually swap the card out at
about 75% full. Has anyone else seen this?

Roger


I don't know, but I will say that I have noticed that **playback** of images
slows with a full card vs. a mostly empty card (microdrive).

Do you format the card each time, or just delete?

I format opften, but occasionally delete all. On the 4GB card, I have
only formatted, as it is much faster.

Are you deleting files here and there as you go?
Never.

These things could be causing fragmentation.
I know that you might not be using a hard drive (microdrive), but it is my
impression that even with solid state memory, the controller still has to
organize the space on it similarly to a hard drive. As the drive fills, it
may be jumping around looking for blocks to partially fill... I don't know
for sure, and someone more in-the-know may pounce on me with a nasty
correction...but this makes sense to me.

The part that does NOT make sense is that one image format over another
would be more problematic than another (assuming the storage space required
is similar).

David J Taylor wrote:

Roger N. Clark (change username to rnclark) wrote:

Question. Has anyone observed a slowdown in the write rate
of images to a large compact flash card when the card gets
close to full with a large number of images? I have several
2 GB Lexar 40x and 2 GB Sandisk Ultra II cards and when writing
highest quality jpegs on a ID Mark II I see no problems
with write speed, even up to the last image.
But I also have a 4GB Lexar 40x card,
and as it fills, say starting around 900 images (~75% full),
the write speed slows way down. I haven't noticed that same
problem with Raws, but then I usually swap the card out at
about 75% full. Has anyone else seen this?

Roger


Yes, I reported this many threads ago, based on using a Nikon Coolpix 990
with about 400+ images per 128MB card.

My conclusion was that the problem was most likely due the the number of
files in a directory, and using the FAT rather than the NTFS file system.
The newer Nikon cameras limit the number of files in a single directory to
200 (I think) and the slowdown is reduced or eliminated.

This could be the problem. My 10D puts a maximum of 100 files
in a directory, the 1DII puts all the files in one directory,
so potentially over a thousand.

As you have a 4GB card, it could be a FAT32 versus FAT16 issue, with the
camera's firmware perhaps not supporting FAT32 quite as well as FAT16?

I believe the 4GB card auto formats to FAT32.

Roger

David J Taylor wrote:

Roger N. Clark (change username to rnclark) wrote:

Question. Has anyone observed a slowdown in the write rate
of images to a large compact flash card when the card gets
close to full with a large number of images? I have several
2 GB Lexar 40x and 2 GB Sandisk Ultra II cards and when writing
highest quality jpegs on a ID Mark II I see no problems
with write speed, even up to the last image.
But I also have a 4GB Lexar 40x card,
and as it fills, say starting around 900 images (~75% full),
the write speed slows way down. I haven't noticed that same
problem with Raws, but then I usually swap the card out at
about 75% full. Has anyone else seen this?

Roger


Yes, I reported this many threads ago, based on using a Nikon Coolpix 990
with about 400+ images per 128MB card.

My conclusion was that the problem was most likely due the the number of
files in a directory, and using the FAT rather than the NTFS file system.
The newer Nikon cameras limit the number of files in a single directory to
200 (I think) and the slowdown is reduced or eliminated.

This could be the problem. My 10D puts a maximum of 100 files
in a directory, the 1DII puts all the files in one directory,
so potentially over a thousand.

As you have a 4GB card, it could be a FAT32 versus FAT16 issue, with the
camera's firmware perhaps not supporting FAT32 quite as well as FAT16?

I believe the 4GB card auto formats to FAT32.

Roger

Roger N. Clark (change username to rnclark) wrote:
[]
My conclusion was that the problem was most likely due the the
number of files in a directory, and using the FAT rather than the
NTFS file system. The newer Nikon cameras limit the number of files
in a single directory to 200 (I think) and the slowdown is reduced
or eliminated.

This could be the problem. My 10D puts a maximum of 100 files
in a directory, the 1DII puts all the files in one directory,
so potentially over a thousand.

The FAT file system simply is not designed for such a large number of
files (directory entries) - NTFS is. No choice on a camera, of course.
Another issue (although not relevant here) is the use of long file names.
As each long file name uses more than one directory entry, the capacity of
FAT is even more limited that you might expect.

Cheers,
David