#Cache Benchmarks
34 messages in this thread
I would be interested in providing those of you who are interested with
specific benchmark data on our CD-ROM caching product. It provides
specific benchmarks on the following titles: MAMMALS, WORLD ATLAS, US
ATLAS, and US HISTORY. I would be happy to send them to anyone who is
interested in quantitative results. Overall, we've found that an average
of between 500% – 700% should be seen. However, we have seen specific read
access times drop an incredible 8000%. Let me know if you are interested.
Does this forum have a policy _against_ uploading such things into the
libraries?? If not, why don't you do that…then we can all get them if we
want. If so, why the policy??
I'm not sure, so if there is a consensus among users and there's no
problem, I would be happy to do it. Reese
Reese – picked up your .BIN file from Mail this evening. Now my question is,
what is the file – .ZIP, .EXE or …? I suppose I could look at it with a
sector editor and figure it out, but its getting late and I'm in Recon, so
this message looks quicker.
Thanks for the file; look forward to testing it on my CD-ROM when I know what
it is.
Regds Ric
Ric, Sorry for the confusion. It is a .TXT file You can download it using
CDBENCH.TXT as the file name. Someone here has been playing with my
protocals, and I don't like it! I hope to have the info. posted on the
board for CD Speedway by tommorrow…once again, my apologies. Reese
Reese – appreciate the quick reply; will read it just as soon as I get out
of Recon (have been off CIS for over 4 months while moving my family from
Hong Kong to Canada, so am doing some _major_ catch-up forum
reading/scanning!
Regds Ric
No problem Ric, hope to hear from you soon. Reese.
I'm interested,
RK
Yes, I would be interested — how do I apply?
I'm interested in your product. Something more than guesses.
Kieth, I'm not quite sure what you mean by guesses? so I'll be happy to
send you whatever infor. you would like. Let me know what data you need,
and I'll get it to you.
Reese, right now I'm just guessing at what your product is or isn't.
Please E-mail some literature of what the product is and what it is
supposed to achieve. I am interested in any trick that can make a 7205
faster in data transfer. TIA, Keith.
Keith, There's really no need to guess at what CD Speedway does. Simple,
yet highly effective, CD Speedway uses "caching" technology to take full
advantage of the "basic" fact that different parts of your computer work at
different speeds. Your RAM is much faster than your hard disk. You hard
disk is much faster than your CD Reader. For example, a CD Reader can move
a piece of data in about 350 milliseconds, which is slower than 1/3 of a
second. A hard disk can move data in about 17 milliseconds, which is 17
thousandths of a second. RAM can move data in about 70 nanoseconds, which
is 70 billionths of a second. In other works, a hard disk is about 20
times faster than a CD reader, and RAM is @ 240,000 tims faster than a hard
disk. Caching with a CD reader means that when data is read from a CD, it
is also copied to another, faster location and stored in a "cache". The
cache could be a file on a hard disk (if you don't have enough RAM to make
a RAM disk). Then, if that same data is needed again (which happens a lot),
it is read from the faster location. When the needed data is already in
the cache, the slow CD reader doesn't have to retrieve it a second time.
And you end up with a noticeably faster application. (Sorry for the
dissertation, but this should help you understand better what CD Speedway
does). Reese.
How does this differ from the buffers allocated by MSCDEX? Using expanded
memory I allocate 1MB of buffers to MSCDEX and yes it does speed up
operations quite a bit. How does CD Speedway do it's caching that makes it
so much different?
Craig
Craig,
Buffers are more like a traditional cache, (a la FAST!, Smartdrv), where
MSCDEX gets the data at a device driver level (intercepting INT calls)
grabbing this traffic. CD Speedway, on the other hand, is a pure file
cache working at the DOS level to cache files (*.exe, *.*, etc.).
The two would work well in conjunction with one another, by 1) cutting your
buffers to 256K-512K to grab directory and FAT info, and 2) by adding CD
Speedway to grab files.
Reese.
Sounds interesting.. I ordered a copy of CD Speedway last week so hopefully
I'll get a chance to try it out in the next couple of days.
Craig
Thanks for the reply Reese. I am aware of the nuances of caches and
buffers. I use the system cache in the 486 chip, a 2 Meg disk cache for
the hard drive and expanded memory buffers for MSCSDEX. My question is how
do you get a disk cache to work with what DOS and Windows consider a
network drive? If are accessing a CDROM database, then your explanation of
cache hits makes sense. But, on the other hand, if you are running MM
video and audio passages, which are primarily linear and non-repeating, how
can your product speed up a basic problem of data transfer rate? Thanks
for reply. Keith.
Keith,
Good question. CD Speedway is not a BIOS based product. It does not cache
the INT's so common to BIOS based products such as FAST! or Super PC Kwik.
As a matter of fact, our network cache should start shipping for Novel
shortly. Sorry, a little off the subject.
Speedway is a pure file cache. It works at the DOS level capturing
significant "file" information. You may set the product up to cache, for
example, all *.exe files. It's read ahead algorythm means that even first
accesses are speeded most of the time. We don't do much for your Data
Transfer Rate. This, in a lot of cases is locked in by the format of the
CD ROM. (For example the Philips XA format.) What we do help, though, is
initial access time. Imagine if your hits are grabbing not only
information accessed again, but first time info. In this way you are
bypassing the extremely slow access time and DTR of the Reader, and gain
the advantage of high speed RAM.
Because we improve your accesses as much as 8000%, Your overall performance
is improved by folds! Using the MSCDEX buffers parameter in conjunction
with CD Speedway should give you excellent results. I have recommended
using between 256K and 512K of buffers to grab directory and FAT info. and
give CD Speedway the rest. Reese.
How would you anticipate CD Speedway working in this configuration:
I have 6 CD-ROM drives connected to a 386sx machine. This machine runs a
BBS in which there can be up to 6 people accessing the CD-ROMs. The CD-ROMs
are used exclusively for callers to download files (mostly
ZIP files).
In effect the callers are "copying" files in their entirety from the
CD-ROMs thru the modem. These files are "copied" in 1K chunks. Most files
are in the 250K to 500K range in regards to size.
If you could elaborate on "file caching" it would be appreciated.
Craig
Craig,
I would anticipate an improvement in overall throughput but would think
that your bottleneck is probably the modem???…In effect the cache would
"hurry up and wait". Since you did not say what speed your modem is
running, I believe this scenario is a try it and see. Run with a 1.5 Meg
to 2 Meg. cache with 6 concurrent users. This way ll files will be cached
properly. Reese.
I received my CD Speedway today. I have to admit so far I'm not impressed.
I ran some benchmarks on the following discs: TigerDemos, Front Page News,
ROMWARE Magazine and disc/in/DISC. My average increase was 4% with CD
Speedway. The maximum increase was 25%. With one demo on the TigerDemos
disc CD Speedway was 400% SLOWER!!
I am using a Chinon CDS-431 drive with a 2MB Ramdisk for CD Speedway.
Is there anything special I need to do to get the large increases shown in
your benchmarks?
Craig
Craig,
David Kessler will be responding to you on this issue. You probobly need
to tweek the software. He'll help you out.
Reese.
Thanks for the reply Reese. I guess I will wait until I get the next BLOC
or Tiger catalog to read up on the product. Keith.
I hope I didn't sound too winded in my reply(s) to you Keith. I sometimes
forget to keep things short and simple. BLOC is sending Speedway demos to
all dealers of NEC and Philips drives as we speak, so contact your local
dealer as well.
Reese.
No, I wasn't affronted Reese. Besides, sometimes, unnecessary explanations
are beneficial for all the 'lurkers'and you can't really tell about the
technical expertise of an online persona unless you've conversed before or
read a lot of their threads. Thanks for the tip on the Speedway demo. Now
I have another reason to pester my local NEC dealer. Maybe if he sees me
enough times he will get the messsage across to his purchasing agents to
step up the heat on NEC to get more of the 73M and 83M's into the
distribution channel. Cheers, Keith.
Keith,
I personally think the 73M is hotter looking as an external unit.
Reese.
Reese,
I would be very interested in hearing more about this product.
Please reply via Email.
Pete
Peter, Info. on Speedway should be in your box by the time you read this.
As the product sells to more and more people, I'm sure you will be hearing
much more about it!. I hope you become one of our users soon. Thanks,
Reese.
Reese,
Very interested in your product.
robin
Thanks Robin, as you may have heard, BLOC Publishing is doing a great job
for us bringing this product to market in a timely manner. You can
download the benchmarks from the library, or if you prefer, contact me via
my box, and I'll be happy to send you more info. (Whatever you need.)
Reese.
Gosh, Reese, I haven't heard a thing–and I get stuff from BLOC all the time.
Tell me how to get the program. If you want to fax stuff, our # is
503/624-7778
robin
Robin,
The product is in the pipe. BLOC Publishing has done a heck of a job
providing packaging and marketing colateral in a timely manner. Check out
Tiger Software's new catalog, as well as advertising in a number of PC
Periodicals. TIGER's number is 800-88-TIGER.
If you can't wait, give me a call. I'll be happy to ship it to you.
Reese,
Hey, I was never good at waiting, either for a product or for my CD-ROM!
What's the deal?
robin
robin,
No need to fear. CD Speedway is here! Give BLOC a call, you shouldn't
have to wait more than FEDEX shipping takes to get to you.
Reese.