PC card reader

[Jouni]

Hi,

No answers in General Forum so I repeat here:

Is PC card reader practically same as USB interface? Or is it maybe faster with fast memory card?
Can it be used as additional RAM or disk storage for tablebases? Any experiences? Thanks in advance,

Jouni

[CRoberson]

Hi,

No answers in General Forum so I repeat here:

Is PC card reader practically same as USB interface? Or is it maybe faster with fast memory card?
Can it be used as additional RAM or disk storage for tablebases? Any experiences? Thanks in advance,

Jouni

I would not use a serial device for tablebases. Remember, internal RAM and hard drives have parallel access. So, USB thumb drives are not as fast as internal RAM,

[wgarvin]

Hi,

No answers in General Forum so I repeat here:

Is PC card reader practically same as USB interface? Or is it maybe faster with fast memory card?
Can it be used as additional RAM or disk storage for tablebases? Any experiences? Thanks in advance,

Jouni

I would not use a serial device for tablebases. Remember, internal RAM and hard drives have parallel access. So, USB thumb drives are not as fast as internal RAM,

That's not a good reason to not use them. USB 2.0 has a raw data rate of 480Mbps. The real reason not to use flash drives or memory cards over USB would be that the devices+drivers end up being slower than a traditional IDE or SATA spinning-platter hard drive.

See for example:
(from 2008) http://www.codinghorror.com/blog/2008/0 ... mance.html
(from 2007) http://www.xbitlabs.com/articles/memory ... undup.html

Also, I think memory cards are kind of expensive (I haven't really checked though). USB flash drives are cheap up to maybe 16GB sizes, but they are still slow compared to a regular hard drive.

On the other hand, good SSD drives are getting very fast now, but they are also still VERY expensive.

(from 2010) http://www.itproportal.com/storage/news ... stest-ssd/
(from 2009) http://anandtech.com/show/2899

[jwes]

Hi,

No answers in General Forum so I repeat here:

Is PC card reader practically same as USB interface? Or is it maybe faster with fast memory card?
Can it be used as additional RAM or disk storage for tablebases? Any experiences? Thanks in advance,

Jouni

I would not use a serial device for tablebases. Remember, internal RAM and hard drives have parallel access. So, USB thumb drives are not as fast as internal RAM,

That's not a good reason to not use them. USB 2.0 has a raw data rate of 480Mbps. The real reason not to use flash drives or memory cards over USB would be that the devices+drivers end up being slower than a traditional IDE or SATA spinning-platter hard drive.

See for example:
(from 2008) http://www.codinghorror.com/blog/2008/0 ... mance.html
(from 2007) http://www.xbitlabs.com/articles/memory ... undup.html

Also, I think memory cards are kind of expensive (I haven't really checked though). USB flash drives are cheap up to maybe 16GB sizes, but they are still slow compared to a regular hard drive.

On the other hand, good SSD drives are getting very fast now, but they are also still VERY expensive.

(from 2010) http://www.itproportal.com/storage/news ... stest-ssd/
(from 2009) http://anandtech.com/show/2899

For tablebase use, which are generally 8KB random reads, my usb flash drive is much faster than my hard drive. Access times completely dominate data transfer times in this application.

[wgarvin]

I wonder how much the Windows disk cache is affecting the performance? Most machines these days will have several GB of RAM being used for disk cache all the time, so if you play a match that uses a certain endgame TB and then an hour later you play another match that needs the same TB, there's a good chance that some of the pages being read will come straight from RAM.

It also may depend on your hard drive. There's average seek time, plus latency. I think most drives have a seek time in the 8 to 10 ms range, and more latency in the 3 to 5 ms range. At home I have a WD Velociraptor which supposedly has an average seek time of 4.6 ms and a latency of 3 ms. I haven't done any speed tests with it or anything. But subjectively, my current computer feels extremely fast compared to the previous one (when I boot the system or launch an application, for example, it loads noticably faster -- both systems using Windows XP with all unnecessary services etc. disabled.)

Now I could totally believe that USB flash drives manage to have lower latency, probably sub-millisecond latency? I could also believe much higher numbers of IO requests per second (IOPS) for small random accesses. I guess where they fall down is on bandwidth. But for IOPS, most hard drives can do 100-200, the Velociraptor can supposedly do about 270 of them, and expensive SSDs can do tens of thousands.

Anyway, it sounds like USB flash drives are a cheap and reasonable choice for putting tablebases on.

[CRoberson]

Hi,

No answers in General Forum so I repeat here:

Is PC card reader practically same as USB interface? Or is it maybe faster with fast memory card?
Can it be used as additional RAM or disk storage for tablebases? Any experiences? Thanks in advance,

Jouni

I would not use a serial device for tablebases. Remember, internal RAM and hard drives have parallel access. So, USB thumb drives are not as fast as internal RAM,

That's not a good reason to not use them. USB 2.0 has a raw data rate of 480Mbps. The real reason not to use flash drives or memory cards over USB would be that the devices+drivers end up being slower than a traditional IDE or SATA spinning-platter hard drive.

See for example:
(from 2008) http://www.codinghorror.com/blog/2008/0 ... mance.html
(from 2007) http://www.xbitlabs.com/articles/memory ... undup.html

Also, I think memory cards are kind of expensive (I haven't really checked though). USB flash drives are cheap up to maybe 16GB sizes, but they are still slow compared to a regular hard drive.

On the other hand, good SSD drives are getting very fast now, but they are also still VERY expensive.

(from 2010) http://www.itproportal.com/storage/news ... stest-ssd/
(from 2009) http://anandtech.com/show/2899

I ran several tests using a laptop. The USB 2.0 Thumbdrive was slower than both a ramdisk (internal ram) and the hard drive.

My recommendation for fast tablebase access is to buy and extra 8GB of RAM and use a RAM disk. Of course, you may have an old 32 bit system and can put another 8GB in.

The 60 GB SATA II SSD can be obtained for 140 USD to 200 USD. That will be much faster than a HD or a thumbdrive.

[F. Bluemers]

Hi,

No answers in General Forum so I repeat here:

Is PC card reader practically same as USB interface? Or is it maybe faster with fast memory card?
Can it be used as additional RAM or disk storage for tablebases? Any experiences? Thanks in advance,

Jouni

I would not use a serial device for tablebases. Remember, internal RAM and hard drives have parallel access. So, USB thumb drives are not as fast as internal RAM,

That's not a good reason to not use them. USB 2.0 has a raw data rate of 480Mbps. The real reason not to use flash drives or memory cards over USB would be that the devices+drivers end up being slower than a traditional IDE or SATA spinning-platter hard drive.

See for example:
(from 2008) http://www.codinghorror.com/blog/2008/0 ... mance.html
(from 2007) http://www.xbitlabs.com/articles/memory ... undup.html

Also, I think memory cards are kind of expensive (I haven't really checked though). USB flash drives are cheap up to maybe 16GB sizes, but they are still slow compared to a regular hard drive.

On the other hand, good SSD drives are getting very fast now, but they are also still VERY expensive.

(from 2010) http://www.itproportal.com/storage/news ... stest-ssd/
(from 2009) http://anandtech.com/show/2899

I ran several tests using a laptop. The USB 2.0 Thumbdrive was slower than both a ramdisk (internal ram) and the hard drive.

My recommendation for fast tablebase access is to buy and extra 8GB of RAM and use a RAM disk. Of course, you may have an old 32 bit system and can put another 8GB in.

The 60 GB SATA II SSD can be obtained for 140 USD to 200 USD. That will be much faster than a HD or a thumbdrive.

I use an Emtec 8 Gb. Its faster than the computer's hd for tablebase access.
http://www.open-aurec.com/wbforum/viewt ... 05#p187005
for some usb stick benxchmarks see bottom of this page:http://www.jens.tauchclub-krems.at/dive ... marks.html

[Jouni]

I was curious and did yesterday some testing in my entry level PC (dual with 64b Windows7). The transfer speed form hard disk is as average 30 MB/s (up to 90 MB/s only occasionally) and from card reader 18-20 MB/s. I transferred 5 piece tablebases (Nalimov) to SD card and did some comparison with different endgamesuites like EET. You must be very careful in testing e.g. by rebooting and starting exatly same way always.
Result: access from card reader is slightly FASTER. What's the explanation - different kind of caching?

Jouni

[F. Bluemers]

I was curious and did yesterday some testing in my entry level PC (dual with 64b Windows7). The transfer speed form hard disk is as average 30 MB/s (up to 90 MB/s only occasionally) and from card reader 18-20 MB/s. I transferred 5 piece tablebases (Nalimov) to SD card and did some comparison with different endgamesuites like EET. You must be very careful in testing e.g. by rebooting and starting exatly same way always.
Result: access from card reader is slightly FASTER. What's the explanation - different kind of caching?

Jouni

For the use of endgame tables the transfer speed does not matter,it's the low access time that matters.