[bookport] Re: Sluggishness with too many books in a folder
- From: "ptorpey" <ptorpey@xxxxxxxxxxxxxxxx>
- To: <bookport@xxxxxxxxxxxxx>
- Date: Sat, 30 Apr 2005 14:10:16 -0400
Rob,
Thanks for the clear explanation of what is going on when a folder contains
too many files and one experiences sluggishness in reading/navigation. This
certainly seems to explain most of what is going on.
However, there still seems to be something unexplained in the behavior I am
seeing with my Bookport.
I already performed the test you describe in item 4 (below. Here is what I
did in detail:
1. I had a folder, lets call it folder "A", with about 32 books in it.
They were all DAISY formatted books downloaded from Bookshare.
2. The last 3 books in folder "A" exhibited the sluggish performance
you describe.
3. I deleted all but 8 books in folder "A", including one of the last 3
books which exhibited the sluggish performance. This book was a book about
Enron, so, lets call it the Enron book.
4. I re-downloaded the Enron book from Bookshare and used the Bookport
Transfer program to put it into folder "A" again. Now, folder "A" contains
9 books, with the Enron book being number 9.
5. I noted that the Enron book in folder "A" still exhibited the
sluggish performance (and was surprised).
6. Thinking that the Enron book itself might be the problem, I created
a new folder, call it folder "B", at the same level (root) as folder "A". I
used the Bookport Transfer program to put the newly downloaded copy of the
Enron book into folder "B". Thus, folder "B" now contains only the Enron
book.
7. The Enron book in folder "B" does not exhibit the sluggish
performance when reading/navigating. Thus, the Enron book itself does not
appear to be the cause of the sluggish performance.
8. Now I am checking to see what files are actually in folder "A". I
mis-spoke - One of the books is actually a one volume BRF file from NLS -
the rest are DAISY from Bookshare.
9. Using Windows Explorer to see what is in folder "A", I see 28 files
for the 9 books I have in the folder (including the *.aa files you described
below).
Summary: With only 9 books in the folder, I am still experiencing
sluggishness with the Enron book. When the Enron book is in a folder by
itself, there is no sluggishness.
Now you and Larry indicated that when one gets on the order of 30 books in a
particular folder the user will experience sluggishness. Is this like
falling off a cliff or does the sluggishness slowly get worse with the
number of books in a particular folder? Thus, would you expect the
sluggishness with 9 books in a folder to be about 1/3 as much as when there
are 27 books in a folder? Maybe the sluggishness I'm still experiencing
with 9 books in the folder is actually less than what I remember when there
were 30 books in the folder. My next experiment will be to delete all but
the Enron book from this folder and test the versions in folders "a" and
"b", but I still need some of the books in folder "a".
I would use Windows Explorer to copy the extra books from folder "A" to
another folder, but the way that Bookshare DAISY books get transferred to
the Bookport places books in a folder with names that are not representative
of the titles of the books. Thus, I can't tell from Windows Explorer (or
the Bookport Transfer program) which book is the Enron book. For example,
when I use Bookport Transfer to copy a book to the Bookport entitled
"Enron", it shows up in the Transfer program as "bookshare_1234..." or
something strange. It would be nice if the name which appeared in the list
of books to be transferred showed up as the name in the folder when it is
viewed using the transfer software.
Well, sorry for the long note. I hope this explains the situation.
-- Pete
Date: Fri, 29 Apr 2005 08:51:29 -0400
From: "ROB MEREDITH" <rmeredith@xxxxxxx>
Subject: [bookport] Re: bookport Digest V2 #116
Pete:
Most everything you have said so far does not surprise me. Flash card
speed plays a big roll in this, and speed ratings seem to be pretty
useless at best. Let me clear some things up:
1. Book Port Transfer cannot effect this issue. So, Beta 432 would be
the same as 1.6.0.0.
2. It is doubtful, but not impossible, that firmware 27 or 28 has
anything to do with this.
3. When you put a lot of books in a folder and begin reading them, the
third file created for each book, the ._aa file, will be created last in
the folder. For example, if you load 50 books into a folder, you will
have 100 logical files. But as you read each book, another file is
created for each. Let's say you read books 1 through 5, and the card
becomes sluggish with book 5. Deleting books in the folder will not
help, because book 5 has a file which is way down in the directory
listing; it is at position 105. This file is accessed when
starting/stopping that book, so sluggishness will occur.
4. The only thing that surprises me is that deleting a bunch of books,
including the problem book, then resending the problem book does not
clear up the problem.
I think at this point I would delete the folder, and resend some of the
books. If the problem book is always a problem no matter where it is
placed, let us know.
Rob Meredith
>>> ptorpey@xxxxxxxxxxxxxxxx 04/28/05 07:53PM >>>
Well, I don't understand this behavior either for a CF card. Maybe I
can
never use this folder again and must eventually delete it? This would
mean
that you can't keep on putting books in a particular directory, wiping
them
out, putting more, etc. without leading to degraded responsiveness.
In either case, this is very strange performance. Maybe the folks at
APH
can enlighten us.
-- Pete
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