how to achieve the goal of data acquisition of some hundred MB throughput with PXIe system

[tangliang]

Now i have a system including 8 pxie-6368(the maximum sample rate is 2M, 16 channels, 16bit), pxie-8133, pxie-1082,pxi 8062, hdd 8265. when all 128 channels begin to data acquisition at maximum 2M sample rate . the throughput will be 128*2*2=512MB. i don't know how to achieve this goal with DAQmx.Hope to get your reply. thank u so much!

[Ben]

Divide and conquer!

Break them up into sepearte machine that use shared timing across all of the platforms. You can use SCRAMNet to transfer the data between nodes if required.

Ben

[tangliang]

the system i use has a large throughput up to 500MB or so.some say streaming is a good way. i tried. but now i can just acquire data at a relative low sample rate, 0.7M or so. how can i realise data acquisition at 1.5MS/s even more. thank you!

[DFGray]

You biggest obstacle to success is your storage system.  It takes a fairly beefy RAID system to handle 512MBytes/sec reliably, and the data buses need to support that data rate through the entire data path.  National Instruments has several solutions.  Start with this page, then pick what fits yours needs.  Trying to do this with a single disk will be an exercise in frustration.

Note that with a single disk, you should be able to get about 50MB/sec, more or less, depending on your disk and what else is going on.  You will want to use a producer/consumer architecture for streaming data from your devices to disk to efficiently thread your application.

I would recommend you read the LabVIEW help on dealing with large data sets.  It contains a lot of tips that will help you achieve the maximum speed your system can attain.

If you post your code, we can give you more concrete suggestions.

[LaThoS]

I think he already has a system, including a fairly beefy RAID array - a HDD-8265...

[DFGray]

You're right - I missed that.  His hardware is capable of doing it.  We need to see code before we can make suggestions.