Best use of disk drives for data transfer

I have three different data "disk" drives on my system and I timed transferring 13 GB of data between. The drives are a standard 7500 RPM disk, a pair of 7500 RPM disks in RAID 0, and a solid state flash drive. The times in minutes and and seconds were as follows:
To:| Standard | RAID 0 | Flash
From: | | |
Standard | 6:39 | 2:43 | 3:22
RAID 0 | 2:46 | 4:41 | 3:33
Flash | 2:41 | 1:51 | 16:58
The first thing to notice is that if the source and destination drives are the same then times are much longer. The Flash drive was particularly bad.
The best time was from Flash to RAID 0, but in the reverse direction the time was poorer than a standard disk, suggesting that the flash has a fast read but a slow write.
Conclusion: for disk bound operations, such as transferring DV AVI files with little or no processing use different drives if practicable. In other words, set the scratch files drive to be other than the drive with the source files on it. If possible, put your source files on a flash drive and your scratch files on a RAID 0 drive.
Edit: Sorry for the poor table layout. Two or more consecutive spaces get converted into a single space for some reason.

You can use the error-cluster to detect the end of your queue. The erroroutput of the shared variable will return a -2220 Warning, if it reads a value it has read already before. I attached a modified example and saved it for 8.2 I hope you can open it.
Attachments:
readbuffered82.zip ‏51 KB

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Need to build communication redundancy using serial RS-232 for Data Transfer b/w Host and RT irrespective of TCP/IP Data Transfer

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I want to do data transfer b/w host and RT through RS232 VISA portal whenever TCP/IP ethernet cable has been unplugged from the controller continuosly , it should keep on checking for TCP/IP link re-establishing also , when ever the tcp/ip link established again that time the communication should be using in that link only. This is accomplished by deploying the RT vi as execuatbale file. I made some logic regards to the above said logic , bur it was not working as much I expected.
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Attachments:
TCP_Serial_Host.vi ‏33 KB
TCP_Serial_RT.vi ‏41 KB

even i am new to this topic and i am trying to get familiar with these protocols
refer to tcp server/client examples in labview examples

Advantages of using BAPI over LSMW for data transfer

Hellow,
Can anybody please give an input for advantages of using BAPIs in data transfer compare to LSMW. If we use BAPI for data transfer of master and transaction data how it is more usefull compare to LSMWs developed.
Thanks in advance
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Hi Raghavendra,
Refer the links..may help.....
[http://www.*******************/search?q=BAPIandLSMW+comparision]
[http://www.*******************/search?q=bapi]
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Using a flash drive for data storage - questions

I take video clips whenever I travel and when creating DVD videos, want to intermix the clips with still images. Over a long trip, so many videl clips are created that it is required to download these to free up space in the camcorder. For me, a flash drive (or pen drive) is an ideal medium. However, I have found that even with a "fast" drive having a spec of 20MB/sec read and 18MB/sec write, the data transfer slows significantly when the transfer is of either video (.AVI) or music (.mp3).
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When I look up transfer rates on the net, it gives one figure specifying this as "data transfer". I could find nothing to indicate the change, if any, in this rate if video or audio files are transferred.
Does anyone have experience with this? Basically, I am trying to find the fastest 2 GB minimum flash drive at a reasonable price, but will I lose all of the speed as a function of the type of file.
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Yes, if these are normal data files and the flash drive is formatted for Mac OS Extended (Journaled) or FAT32.

Creating multiple libraries and using an external drive for data

I'm a recent switcher and new to iphoto. On the windows platform, I used adobe album. I have a around 10k of images that I put on an external drive which is attached to my new imac. I deleted the iphoto folder and redirected it to my images on my external. All is working great. I'm looking for some advise on work flow of file/iphoto management. i.e. I'm assuming the more images I accumulate, the slower I photo is going to run? I hear you can create multiple iphoto libraries. Will that only load the photos that are associated with the library and I'm assuming optimize iphoto's performance versus always loading every photo you have taken every time you work in iphoto? If adding libraries is the way to go, can someone direct me to instruction on how to do this?
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Joe:
I'm assuming the more images I accumulate, the slower I photo is going to run?
You'll have to get quite a lot of photos into iPhoto before you start to see a real slowdown in performance. Users have reported libraries of 40K files and they perform just fine. However, do not keep all of rolls open as that will really do a job on the performance. Just open the rolls you need and close them all before quitting.
Yes, you can use multiple libraries and only load what's in each. I use iPhoto Library Manager to manage and move quickly between 10 libraries. With the paid version of iPLM you can move albums and/or rolls between libraries as needed and keep the keywords, ratings, and comments intact.
Using an external HD in order to maintain sufficient free space (10G minimum is what I recommend) on the boot drive to help optimize performance is a very good idea.
As far as any negative aspects, it would be a good idea to have a second external HD as a backup to the working external HD. You can't be too careful with those image files (and other important files) that can't be replaced.
Do you Twango?
TIP: For insurance against the iPhoto database corruption that many users have experienced I recommend making a backup copy of the Library6.iPhoto database file and keep it current. If problems crop up where iPhoto suddenly can't see any photos or thinks there are no photos in the library, replacing the working Library6.iPhoto file with the backup will often get the library back. By keeping it current I mean backup after each import and/or any serious editing or work on books, slideshows, calendars, cards, etc. That insures that if a problem pops up and you do need to replace the database file, you'll retain all those efforts. It doesn't take long to make the backup and it's good insurance.
I've written an Automator workflow application (requires Tiger), iPhoto dB File Backup, that will copy the selected Library6.iPhoto file from your iPhoto Library folder to the Pictures folder, replacing any previous version of it. You can download it at Toad's Cellar. Be sure to read the Read Me pdf file.

Use of Shared Variables for data transfer from a RT traget to a desktop application

Hi,
I want to adopt the shared variables to share data in an existing distributed application comparable with the T3 Benchmark configuration in this document:
[1] http://zone.ni.com/devzone/conceptd.nsf/webmain/5B4C3CC1B2AD10BA862570F2007569EF
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Regards Till

You can use the error-cluster to detect the end of your queue. The erroroutput of the shared variable will return a -2220 Warning, if it reads a value it has read already before. I attached a modified example and saved it for 8.2 I hope you can open it.
Attachments:
readbuffered82.zip ‏51 KB

The i pod module for data transfer

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Hi,
Retrieve data file from presentation server(Upload from PC)
DATA: i_file like rlgrap-filename value '/usr/sap/tmp/file.txt'.
DATA: begin of it_datatab occurs 0,
row(500) type c,
end of it_datatab.
CALL FUNCTION <b>'GUI_UPLOAD'</b>
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Pls reward points.
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HT5287 If DVD Movies, Audio CD's and even burning CD and DVD's are not supported, what is the point of DVD & CD Sharing then? Wouldn't it just be better to remote in or use a thumb drive if it's only able to be used for data transfer?

If DVD Movies, Audio CD's and even burning CD and DVD's are not supported, what is the point of DVD & CD Sharing then? Wouldn't it just be better to remote in or use a thumb drive if it's only able to be used for data transfer?
Or am I missing the bigger picture?

As long as you have a Superdrive or an external burner/drive, burning, watching, installing, etc. from CD or DVD will work just fine. And so will sharing.

Using Nokia 1200 CA45 connection for data transfer

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About my problem above, i followed the process below which is written in the user guide :
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Connect the cable of data USB on the basis of the apparatus. To
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HT3275 I am using an external drive for backup. I am now getting a message that the drive needs a disk repair, but when I run disk repair it just seems to freeze.

I am using an external drive for back up. Yesterday the backup failed and I received a message that the external drive( a passport drive) needed a 'disk repair", when I ran disk repair nothing happened it seemed to freeze. Suggestions? should i simply erase the external drive and start over-my computer is fine.

Get a different drive for backup.
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JPA - Best Practice For Data Transfer?

I've been considering an alternative method for data transfer between applications, by using Serialized or Encoded to File JPA Entities. (either Binary or XML)
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ICE

jschell wrote:
In summary you are moving data from one database to another. True
You only discussed flow one way. Well the process is meant to be bi-directional. Basically what I envision would to have something like:
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then on the destination pc
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Flow both ways is significantly more complicated in general.Well if well done it shouldn't be
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Does this make the problem clearer?
ICE

How many disk groups for +DATA?

Hi All,
Does oracle recommends having one big/shared asm disk group for all of the databases?
In our case we going to have 11.2 and 10g rac running against 11.2 ask...
Am I correct in saying that I have to set asm’s compatibility parameter to 10 in order to be able to use the same disk?
Is this is a good idea? Or should i create another disk group for the 10g db’s?
I’m assuming there are feature that will not be available when the compatibility is reduced to 10g...

Oviwan wrote:
what kind of storage system do you have? nas? what is your protocol between server and storage? tcp/ip (=>nfs)? fc?....
if you have a storage with serveral disks then you create mostly more than one lun (raid 0, 1, 5 or whatever). if the requirement is, that you need a 1 TB diskgroup, then I would not create 1 1TB lun, I would create 5x200GB lun's for example, just for the case that you have to extend the diskgroup with a same lun size. if its 1 TB then you have to add another 1TB lun, if there are 5x200GB luns then you can simply add 200GB.
I have nowhere found a document that says: if you have exactly 16 lun's for a diskgroup it's best. it depends on os, storage, etc...
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•Ensure that all Oracle ASM disks in a disk group have similar storage performance and availability characteristics. In storage configurations with mixed speed drives, such as 10K and 15K RPM, I/O performance is constrained by the slowest speed drive.
•Oracle ASM data distribution policy is capacity-based. Ensure that Oracle ASM disks in a disk group have the same capacity to maintain balance.
•Maximize the number of disks in a disk group for maximum data distribution and higher I/O bandwidth.
•Create LUNs using the outside half of disk drives for higher performance. If possible, use small disks with the highest RPM.
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•Choose a hardware RAID stripe size that is a power of 2 and less than or equal to the size of the ASM allocation unit.
•Avoid using a Logical Volume Manager (LVM) because an LVM would be redundant. However, there are situations where certain multipathing or third party cluster solutions require an LVM. In these situations, use the LVM to represent a single LUN without striping or mirroring to minimize the performance impact.
•For Linux, when possible, use the Oracle ASMLIB feature to address device naming and permission persistency.
ASMLIB provides an alternative interface for the ASM-enabled kernel to discover and access block devices. ASMLIB provides storage and operating system vendors the opportunity to supply extended storage-related features. These features provide benefits such as improved performance and greater data integrity.
one more question about fdisk partitioning. is it correct that we should only create one partition per luns (5x200Gb luns in my case) is it because this way i will have more consistent set of luns( in term of performance)?

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I was thinking of replacing the 500gb in my 2 year old t430s with a solid state. Prices have come down.
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Thanks.

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My external hard drive is 'seen' by my iMac and I can go into the Finder and open files and folders. I am using the hard drive for Time Machine back up. However Time Machine says it can't find the drive. Same thing has happened with Final Cut Express.

My new LaCie external hard drive is 'seen' by my iMac and I can go into the Finder and open files and folders. I am using the hard drive for Time Machine back up. However Time Machine says it can't find the drive.
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I've run out of ideas. Help would be very much appreciated. Thanks.

have you done some searches on FCPx and time machine? Is there a known issue with using a TM drive with FCPx? dunno but ...wait...I'll take 60 sec for you cause I'm just that kind of guy.... google...." fcpx time machine problem" Frist page link
http://www.premiumbeat.com/blog/fcpx-bug-best-practices-for-using-external-hard- drives-and-final-cut-pro-x/
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booya!

Going from xp to windows 7 64 bit using an external drive for music storage

Greetings Techies!
I hope you all are well.
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Best use of disk drives for data transfer

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