The company at which I am working have finally decided that they need to log data from their equipment, which has an interface that is mechanically compatible with SATA, and could implement a 3Gb/s SATA 2 interface.
Reading the Seagate Barracuda 7200.11 datasheet at
formatting link
I note that the "Sustained Data Rate OD" is between 105MB/s and 120MB/s, depending on precise model. We need at least 90MB/s per data channel... Is that likely to be about the best acheivable for SATA 2? Or can you suggest a faster SATA 2 disk drive family?
Thanks in advance!
--------------------------------------- Posted through
Do you need "90MB/s" *continuously* (sustained indefinitely)?
Keep in mind that you still have to be able to *move* 90MB/s through your filesystem stack (i.e., make sure your OS-I/O can actually do what you need).
And, recall the drive will also do periodic thermal recalibrations which will reduce the drive's "availability", temporarily.
As others already mentioned, RAID systems can easily reach transfer rates of several hundred megabytes/sec using commercial level disks.
For a recent example, I just installed Solaris 11 on an HP Proliant Microserver. Simple tests using dd and files of 1Gb and 2Gb produced more than 200Mb/sec on an redundant (raidz2) disk pool, and close to
400 Mb/sec on a stripped disk pool. All this with an AMD low power processor (just above Intel's Atom,) and using "green" 5900 RPM disks. (5 drives)
You can buy external enclosures that would "strip" a group of disks. without the need to configure an external OS, drivers, etc. They came with eSATA, fiberchannel or iSCSI (ethernet) interfaces. (eSATA may require disk multiplexing support from your SATA interface)
If you have (or can add) a fast network interface, iSCSI may be a good approach..
For RAID based solutions, the bottleneck is more likely to be on how to transfer the data to the disk array system, not to the disks themselves.
Try asking in a file server or data base server forum. Those guys need to solve this type of problem every day.
-- Roberto Waltman
[ Please reply to the group. Return address is invalid ]
Yes, but (below) you mention "capture sessions" -- suggesting there are "non-capture sessions" as well. So, the question then becomes, how long (in terms of data) are these sessions?
OK. But you'll still need a mechanism to move bytes from the application layer down through to the I/O subsystem.
A/V drives don't run these calibration cycles (or at least not as *often*).
You may be able to "ride one out" if you have enough buffering in the host (plus the drive itself). You'd have to look at the specifics of each drive (I've never had to deal with that aspect).
ElectronDepot website is not affiliated with any of the manufacturers or service providers discussed here.
All logos and trade names are the property of their respective owners.