how to format a drive in 64KB clusters

[garyellis]

I have an existing 250GB drive.. I wiped it clean and reformatted it to use with Sage recordings. But, I was not given an option to format it with a 64KB cluster size. So, it formatted with 4KB clusters.

I'm using XP sp2...How do I reformat this drive with 64KB clusters?

Also, once I have done that, I want to put this drive and another 250GB drive together in a "Stripped" raid config to make them act as one drive. Which RAID option do I use and how is the best way to do this without messing up my other drives that I want left as they are?

Thnaks,

Gary Ellis

[GKusnick]

Apparently the right-click Format command doesn't offer a 64K option; I'm not sure why. Use Disk Manager instead (Administrative Tool > Computer Management > Disk Management).

RAID is something you set up before you format the drive, not after. But what advantage are you hoping to gain from a striped RAID configuration as compared to simply adding both drives to Sage as separate recording drives? Striped RAID has no redundancy, so if one drive fails you lose everything on both drives.

There are a number of existing threads discussing the pros and cons of RAID, but the consensus seems to be that there's not much point to it for Sage unless you go to a full-blown hardware-based RAID5 setup with at least three drives. At least that's my impression; no doubt there are other opinions.

[garyellis]

Thank you...

I have read many of the threads and seen the different opinions...

My "little" mind believes that most of the "time" spent with Hard drives is the read/ write access time. If i have 2 separate drives then when I read/write to either, I have 1 access point. If I can combine the 2 drives and have them thought of as 1, then I have 2 read / write access points. So, I believe that the read/write access time is spread over 2 drives, instead of 1...thus, it should increase drive read/write time.

I'm certainly not an expert, but, I read this somewhere else and it made sense to me. So, since I have (2) 250GB drives, I can either use them as 2 separate drives or as (1) 500GB drive with double the access points...

Try this link http://www.hardwaresecrets.com/article/393

Makes sense to me..

Thanks for the input...

Gary Ellis

[GKusnick]

In principle you're correct; striping the drives can increase the throughput for disk-intensive tasks. However I think the point with respect to Sage is that recording a single program is not all that disk-intensive; the data rates, even for HD, aren't high enough to make drive throughput an issue. And for multiple simultaneous recordings, you don't need RAID to balance the load across multiple drives; just direct each tuner to a different drive in your .properties file. So while striping may sound good in theory, in a practical Sage system it doesn't actually buy you much except the chance to lose everything if one drive fails.

[garyellis]

That is definately an idea to try....

There are a few problems I am trying to solve...All seem to point to Hard Drive congestion...

Last week, I was recording 2 HD programs from my HDHR tuners and was also recording an SD program via a Hauppauge 150 tuner. At the same time I was watching a previously recorded HD program. All this was reading and writing from the same Hard Drive. The Recorded HD program started to stutter. It was a very rythmic stutter..about every 5 seconds.... The shows that were recording did just fine, no problem. When the programs stopped recording, the the HD recorded show played just fine.

The second problem...Any time I run comskip while recording an HD show, I get the 5 second rythmic stuttering, when both are reading and writing to the same Hard Drive.

I have a quad core processor, so I believe it has something to do with my Hard Drive read/write speed... (maybe could be the network, but I'm leaning toward Hard Drive congestion)

Any suggestions are welcome,

Thanks...

Gary Ellis

[null_pointer_us]

Most of the problem is related to scheduling of reads/writes, not throughput.

Reading/writing data to disk relies on the physical drive head (which does the reads/writes) moving to particular parts of the disk. This occurs while the internal disk platters (on which the data is stored) are moving at a fixed rate of speed. However, system calls don't expose all this timing data to running applications, so the reads/writes come in a fairly arbitrary and very suboptimal manner.

Operating system calls try to reorder the read/write requests from running applications (e.g. SageTV and comskip) to minimize delays due to the disk heads and platters.

However, applications do not normally expose details about their own timing and how future reads/writes might impact application performance. An archival program, for example, streams large amounts of data, but it can run in the background, so unexpected hiccups in I/O performance aren't significant. But a media program requires a small amount of I/O on a predictable schedule because it's displaying data at a constant rate. Algorithms can be written to detect such things, but it can never be perfect.

Finally, Windows isn't really designed for this sort of thing. Periodically, Windows does some weird I/O in the background for no apparent reason, i.e. the hard drive goes crazy for ten minutes at a time. Disk instensive stuff also gets scheduled for you: antivirus programs, Windows Defender, Windows Update, and the built-in Disk Defragmenter tend to run in the middle of the night. Make sure to disable that if you haven't already.

Your hardware is probably quite capable of doing all that stuff at once. To prevent Windows from mucking everything up, I highly recommend using a dedicated disk on a dedicated channel (PATA or SATA) for TV recordings. That way Windows attempts to access the application/system files and page file will not interfere in any way with your recordings. Also, if you can, configure comskip not to process any media files until the disk itself is idle (more specifically, when the disk is not getting write requests). I use DirMon2 (to schedule comskip as a Windows service), which has options for this.