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bryank

join:2000-03-23
Plainfield, IL

PCI SATA Card Poor Transfer Rate

So I have a Western Digital Live that I use to stream .iso rips of my DVD's through my network to my TV. I am having some lag issues and not sure if it's network related or hard drive transfer rate related. I am to believe my issue is hard drive transfer rate because I just noticed that my PCI SATA Card (VIA VT6421) has a transfer rate of 150MB/s and my new 3TB Hard Drive has a transfer rate of 3Gbps.

Should I replace my old SATA card and get this?
»www.newegg.com/Product/Product.a···16124008


psafux
Premium,VIP
join:2005-11-10
kudos:2
The PCI card is likely your throughput bottleneck.

You could do some benchmarking to figure out for sure though.


bryank

join:2000-03-23
Plainfield, IL
reply to bryank
I actually just did and I think this is where the problem lies.


koitsu
Premium,MVM
join:2002-07-16
Mountain View, CA
kudos:23
Can we see the results of your benchmarking?

The card you linked is a standard 32-bit PCI card, which means at most it's going to be able to push 133MBytes/second and no more. That's a limitation of the 32-bit PCI bus itself. I'd rather not go into discussions about 64-bit PCI or PCI-X and so on.

Moving to PCIe (PCI Express) is the best choice.

However, most present-day mechanical hard disks aren't going to exceed ~180MBytes/second, no matter if they have a SATA150, SATA300, or SATA600 PHY. There are some older models of hard disks that had PATA-to-SATA bridges on their PCBs, but I'm talking about drives circa 2006 and no where near 3TB in capacity.

Furthermore, even if you're on a gigE network, chances are you're not going to be able to pull 133MBytes/second off your LAN (meaning your Ethernet speed is going to be less than the SATA I/O bottleneck). Even on my gigE network at home, using FTP (and only FTP; things like CIFS/SMB result in much slower I/O rates), I'm able to get 97MBytes/second when transferring a file from a ZFS mirror to a standard Windows XP workstation (NTFS filesystem, MHDD).

This topic very quickly delves into the realm of system administration and the number of variables to take into account is something like 20-25. No joke.

My guess is that your problem is probably elsewhere and not with your disk. Terms like "lag issues" are too vague/ambiguous to really mean anything conclusive. Of course, if the 3TB disk, for example, isn't formatted with proper alignment (since it almost certainly uses 4KByte sectors / is an "Advanced Format" drive), then that could explain periodic hiccups, but would be noticed more during writes than reads (though both are impacted).

The OS the source machine runs, NTFS cluster size of the filesystem which houses the .iso files, what kind of SATA controller you're already using (and what driver set/version), etc. all play a role here. Like I said: there's a good 20-25 variables to try and work out. It's a lot easier to do in person.
--
Making life hard for others since 1977.
I speak for myself and not my employer/affiliates of my employer.


bryank

join:2000-03-23
Plainfield, IL
reply to bryank
Well damn...that's alot of info. Here is the benchmark I did with my current PCI SATA card. This is an older machine 2.0ghz, 1 gig ram, running windows 7 32-bit, with the 3TB hard drive being a Western Digital Caviar Green. The motherboard does not support PCI-E and has no SATA connections; hence the PCI SATA Card.

With the benchmark, you can see my over all score is an 85. The C drive (which is IDE with specs of 150MB/s) on that same machine had a bench mark of 450. My other computer with much newer equipment, was a benchmark of 890. So I guess the first thing to try is the SATA card since it only costs $50.


aurgathor

join:2002-12-01
Lynnwood, WA
kudos:1
Reviews:
·Frontier Communi..
Hmmm, you got a Caviar Green. Not exactly the drive made for streaming. Some people don't have a very good opinion about that drive, to say the least, and not without a good reason.

Obviously, replacing the SATA card is the cheapest option, but I'd probably do some testing before. Can you stream files from your C: drive w/o any problems?
--
Wacky Races 2012!


koitsu
Premium,MVM
join:2002-07-16
Mountain View, CA
kudos:23
reply to bryank
Based purely on your benchmarking screenshot, I would say the issue is either with the drive or with the controller, yes. That performance is about 20-22x worse than what it should be.

Can you please use HD Tune Pro (trial is fine; please don't use the free version) and show me a screenshot of the "Health" tab? You may need to resize the window so all the SMART attributes are visible. This will help me try to rule out if it's the controller or the drive.

And what aurgathor See Profile says about the WD Green models of disks is correct. In general they should be avoided, if not just for this.
--
Making life hard for others since 1977.
I speak for myself and not my employer/affiliates of my employer.


bryank

join:2000-03-23
Plainfield, IL
reply to bryank
So using HD Tune Pro there is no Health entries for my WD hard drive, maybe there are no SMART features? My C drive has listings, but that dive is not being used for streaming. Here is a screenshot of my benchmark with HD Tune Pro.


koitsu
Premium,MVM
join:2002-07-16
Mountain View, CA
kudos:23

2 edits
Is this drive attached via USB or eSATA or in a RAID configuration of any sort?

If SATA, what SATA controller model is this hooked up to physically? Are you using Microsoft's drivers or drivers from a vendor? What OS is this exactly (version and bit (32-bit or 64-bit))?

The drive model string is being cut off -- "WD30" doesn't tell me much, but the drive absolutely has SMART (every drive manufactured since roughly 2001 has had this). Theories:

1. I have seen a problem very similar to this on a colleague of mine's workstation, where his SATA controller drivers were broken in some regard and his drive model was getting cut off (the submission CDB worked fine, but the response payload had data in it which was invalid). I forget what model of SATA controller he had, I believe it was nVidia but I can't remember for certain. It definitely wasn't Intel. I had him upgrade his drivers and everything began working correctly.

2. The disk may have some sort of HPA region failure or a mechanical/physical problem of some sort.

3. A very broken/busted SATA cable or SATA port on the motherboard.

Items #2 and #3 would explain crappy performance, as for #2 every single CDB submit to the drive would result in a payload response that was busted in some way, and #3 would manifest itself in a very horrible/very nasty way as well.

To rule out all of these issues, booting into an alternate OS is usually the best choice. I've historically recommended Knoppix, which is a Linux LiveCD-based operating system, to accomplish this task. However in recent days Knoppix has had a lot of compatibility problems with hardware. It would take me quite a while to write up a walk-through on how to do this with a bare-bones terminal-based Linux distribution.

If the problem doesn't happen within Linux (e.g. SMART statistics show up and drive I/O is fine), then the issue is with Windows and/or drivers. If the problem does happen in Linux, then it's either #2 or #3.

Edit: Finnix seems to be a good/legitimate alternate to Knoppix, although their latest build uses smartmontools 5.41 (fairly old). Finnix supports ntfs-3g so you could mount your C: drive and write the smartctl output to a file on that. I think you'd need to do something like this:

ntfs-3g /dev/sda1 /mnt
smartctl -a /dev/sdb > /mnt/drive_d.txt
umount /mnt
reboot
 

/dev/sda should be your C: drive, thus /dev/sdb should be your D: drive (which I assume is the WD30* drive); but it may be /dev/sdc or /dev/sdd if you have other drives in the way (such as CF/SD/MMC drives).

However given what Windows 7 (if it is Windows 7) does with some of its partitioning stuff, /dev/sda1 might not be the right partition to mount for your C: drive, it might be /dev/sda2 or /dev/sda3 or something like that. I really don't know. Stepping someone through this remotely is difficult -- it's one of those things I could do in 10 seconds if I was there in person.
--
Making life hard for others since 1977.
I speak for myself and not my employer/affiliates of my employer.


aurgathor

join:2002-12-01
Lynnwood, WA
kudos:1
Reviews:
·Frontier Communi..
reply to bryank
27.8 MB/s max and 6.9 MB/s average are way-way lower than they should be. Can you put the disk into a machine that has native SATA and test it there?

They have their own issues, but you may also try a SATA to PATA bridge adapter -- given your current transfer rates, it can't be much worse with such adapter.
--
Wacky Races 2012!


bryank

join:2000-03-23
Plainfield, IL
reply to bryank
So I got the new PCI SATA card today and installed it and yup so far so good. I still have not checked it with streaming the .iso's but I am sure it will be good. Also the health status shows entries for that drive, so I think we found the problem.


koitsu
Premium,MVM
join:2002-07-16
Mountain View, CA
kudos:23
That read performance is still absolutely horrible for the drive (unless you ran that benchmark while it was handling ISOs). You should be seeing around 100-110MBytes/second from that drive (it's a WD Caviar Green 3TB).

Please provide a screenshot of the Health tab.

One possibility is that the WD30EZRX has known problems relating to excessive head parking. You can read the details on my blog. The "Green" drives are drives to generally stay away from.
--
Making life hard for others since 1977.
I speak for myself and not my employer/affiliates of my employer.


bryank

join:2000-03-23
Plainfield, IL
reply to bryank
I guess I will try another SATA cable and see if that changes anything. On a side note, I streamed about 15 minutes of an .iso and it played perfectly. That same .iso on the old pci card lagged immediately.


koitsu
Premium,MVM
join:2002-07-16
Mountain View, CA
kudos:23

2 edits
I would hold off on replacing the SATA cable. Please hear me out first (below is how you narrow/troubleshoot an issue of this sort).

The attribute you're concerned with (UDMA CRC errors) see tracks the number of CRC errors during the drive's entire lifetime. As you already know, these are CRC errors accumulated between the SATA host controller (in a PC/system) and the drive. There is no way to clear/zero/reset the attribute so you're going to have to write down the number/remember it.

These may have been incrementing when the drive was being used on the other SATA controller, in which case that seems to imply the issue was with Item #3 in my aforementioned list.

Instead, I would recommend watching the attribute over the next 24 hours. Do some benchmarks, stream some ISOs, etc. and check on it tomorrow. Steps:

a) If the attribute has incremented, examine the SATA connectors on both the drive and the SATA controller. See if the pins look anomalous in some way (gold busted off, etc.). Look for excess dust as well. If there is dust, use some canned air (do not use an air compressor -- that is too rough) to clean them out.

b) If the attribute keeps incrementing after (a), keep the same SATA cable in use but use a different SATA port on your SATA controller.

c) If the attribute continues to increment after (b), replace the SATA cable.

d) If the attribute continues to increment after (c), then what you have is a drive with a faulty SATA interface connector faulty circuitry between the drive backplane and the SATA controller IC on the drive PCB itself -- in which case, RMA the drive.

e) If after a drive RMA you still continue to have the same problem, then you have electrical interference of some sort that is causing serious issues within your case. This type of issue I cannot troubleshoot; it requires a very skilled technician to analyse. Electrical interference may be caused by all sorts of electronic components nearby, it's very difficult to say which. Do not like someone tell you that "the problem is with your 5V or 12V lines coming from your PSU" -- that is nonsense. However, the PSU could be emitting electrical interference of some sort, but the issue is not "with your 5V/12V rails" or anything like that.

Your drive looks perfectly fine otherwise (for a WD Green), with no other anomalies.
--
Making life hard for others since 1977.
I speak for myself and not my employer/affiliates of my employer.