SATA and Raid0 - The definitive guide to being ticked off...

[runningnak3d]

Silicon Image SATA -- you gotta love it.

I have an A7N8X-E with two Hitachi Deskstar 160GB drives in a raid0 setup. Since I have had this rig I have had perfomance issues with the disks. I (like many others) thought that getting fast drives and striping them would be the cats meow. Errrr -- WRONG!

Don't get me wrong ... for raw throughput the setup screams. One small problem however. I can't use my machine for anything else while that massive ammount of disk IO is happening.

Let me give you an example.

I have 50 50Meg rar files, 3 of them are damaged and need to have QuickPAR run on them, I start QuickPAR going and the machine gets sluggish. If I then start ANOTHER QuickPAR on another batch of files ... or if I start unraring a set of files, my machine grinds to a halt. Let me rephrase that -- the QuickPARs and the unraring are really fast (compared to other machines I have tried similar tests on) but I can't continue to use the machine for something as simple as browsing the web until the PARing / RARing is complete.

I have an old Abit KT7 with a 900Mhz Duron in it that I can bring to its knees CPU wise by running 3 or 4 quickpars (my Asus with the XP 3200+ never bumps above 10-15% CPU utilization) but it at least remains responsive -- not SUPER speedy -- but responsive, and not to mention the quickpars take hours to complete.

It almost seems like DMA is off on the Sil controller. I know this is not the case -- I checked with several utils -- but that is what it FEELS like.

After much research, I found some posts about people doing audio recording and getting drop outs when doing multi channel on their Sil raid0 setups. The discussions I read said to try changing the PCI latency ... so I was off to download Powerstrip (I found a much cooler util called simply PCI Latency Tool 2.0 after Powerstip ticked me off). I tried increasing, decreasing (not that you can go much below the default of 32) to no avail.

I only had 512Megs of RAM in my machine -- for these tests I ran the bare minimum of software required by XP. I disabled themes (don't get me started about the bug where you switch to classic and try to switch back with ZoneAlarm running and it just hangs -- THAT was a nightmare to diagnose) and I shutdown ALL services that I could (networking included) to try and have as much ram as I could. When that wasn't cutting it, I threw in another 512Megs. Things are better (wow, I can surf the net while running one instance of QuickPAR and unraring one archive) but I know there is something not right. HDtach, ATTO, HDTune, and SiSoft Sandra all say everything is just great. I will be glad to post some numbers if anyone wants to look.

One last thing, I have Diskkeeper set to defrag nightly and I have manually defragged several times in a row _just to be sure_. I have downloaded the drive test off of Hitachi's website, and it says the drives are fine. I have run memtest86, prime95, 3dmark01 and 03 overnight several times and the machine has never hickuped ... it is rock stable.

If ANYONE can give me some pointer ... some registry setting ... some bubble gum to stick in the corner I would be eternally grateful.

I have done a fresh install and only installed the basics to see if it was something I was installing -- err, not the case.

Here are the specs:

A7N8X-E Bios 1011
Athlon XP 3200+
2X 160GB SATA Hitachi Deskstar HDs
1024MB Micron PC3200 Cas 2-2-2 ram (2 256Meg and 1 512Meg)
Evga GeForce 5900 (driver 66.93)
nForce UDP 5.10 with audio driver 6.14.457
Sil driver 1.0.0.51
Sony DVD-RW on the PATA interface (the only device)
I am using the Marvel Gigabit lan interface (only becuause it was part of my diagnostics -- I thought maybe the nVida lan driver may be giving the Sil driver grief)
There are no other cards in the machine.

PS - I have run permon and watched the average disk queue length -- it hover between 3 and 4 when there is lots of disk IO. Once again the raw throughput is there.

I would really like to solve this insted of going out and getting an add-in SATA raid card ... but if that is my only option I will go that route. I mainly posted this not hoping to get an answer ... but to describe the issues I was having so that anyone else out there that has a similar setup with similar issues knows what has been tried.

--Brian

 

[KGB]

Nak3d,

Welcome to the Forums! :beer:

Okay... I think we all need hip-waders after that enema.
How about posting some HDTach data?

 

[runningnak3d]

Until I read the docs to find out how to post or link to an image this will have to do...


Burst Speed: 121.2MB/s
Random access: 11.2ms
CPU utilization: 3%
Average read: 99.5MB/s

at the end of the drive (array) the read speed is ~63MB/s looking at the graph.


Sorry for the long post ... but this whole ordeal has been kinda frustrating. My old KT7 Raid never gave me this kinda grief.

I'm interested to hear if there are people out there with similar setups that can manipulate multiple huge files and still have a usable machine.

Thanks,

--Brian

 

[mechBgon]

1) PowerStrip is adware. Run teh awAy! :Q Better run some anti-spyware scans with Spybot Search & Destroy, Lavasoft Ad-Aware SE Personal, and maybe that new Microsoft AntiSpyware Beta. If you don't have any antivirus software, or are running some old stuff, Kaspersky (see, I am even speeling it right now) has 30-day trials of their top-notch antivirus software too.

2) Yeah, you have a PCI-based SATA solution. It's apparent in the 121MB/sec peak real-world throughput. It has to share that bandwidth with the rest of your PCI stuff (duh), what else do you have on the PCI bus and which slots are they in? Too bad the MCP-S southbridges are as rare as hens' teeth on the market, they'd move your SATA up to the very hefty Hypertransport link so they're free of the PCI bus. I guess a VIA-based board with native SATA is another option, if you're open to VIA.

 

[VirtualLarry]

PowerStrip is spyware now??? Wow, that's news to me, thanks mechBgon.

I think that the biggest problem is that QuickPAR's recovery option requires: 1) plenty of RAM, 2) lots of disk I/O.

Trying to run another instance of it at the same time (especially the recovery, not just a simple file-correctness scan), will make both of them slow way down. Add to that, if you don't have enough RAM for both of those operations and your normal apps (and 512MB likely IS NOT), then your apps will start paging. Now, if the pagefile, and the files being recovered, and their source files, are all on the same striped RAID array, well, there's your answer. Under a heavy number of I/Os, striping is actually slower than a mirrored RAID array, and both are slower than just ordinary independent disks. The key bottleneck here is seek times, not throughput. Striping is all about increasing throughput, without any serious consideration to the other aspects.

So now you know. RAID striping on the desktop is NOT always a win, and can often be a loss. My suggestion for a config, other than a mirror setup, is to put the OS/paging-file onto one drive, and then have another drive for downloads and doing the QuickPAR repairs, and *don't* try to do more than one repair at once. (At least not on the same physical drive.)

 

[runningnak3d]

mechBgon:

Powerstrip is NOT adware. If you discovered adware after installing it, then you had a corrupt install. Just throwing that out there becuase that is how bad rumors get started. What ticked me off about it was the fact that if you set the PCI latency of a device to 16 or 0 it locked that device out from further changes.

Now back to my issue ... considering the Sil SATA raid controller is on the PCI bus I don't expect anything higher than 121MB/sec peak. As a matter of fact when I first got this rig I was surprised it got that. As I stated in my first post I am not concerned with the throughput. I concerned with the overall lagginess of the machine while GETTING said throughput.

VirtualLarry:

After reading through the QuickPAR forums I realize that it needs lots of RAM. That is why I threw another 512Megs in the machine. But let's be real ... a gig of ram and an XP 3200+ should be able to handle at LEAST 3 or 4 "sessions" if an old KT7 can and still be responsive. Bottom line is the Sil drivers have issues.

I am not going to debate you concerning raid on the desktop, there are enough threads for that. I will say that (if you have a decent raid card and drivers) raid 0 will ALWAYS be faster than a single disk no matter WHAT the application. You have more spindles (hence lower latency), and you have more bandwidth (double for the most part). So, all things being equal ... which they never are, two SATA 150 drives now give you 300MB/sec of POTENTIAL data transfer. I say potential because we all know that even the fastest 10,000 RPM drives out right now can't do 150MB/sec. So what you do get is twice the REALISTIC data throughput.

Thank you both for your input ;-)

--Brian

 

[runningnak3d]

I guess a couple of polite emails to Silicon Image concerning their drivers wouldn't do the trick, huh? What I don't understand is why there isn't more info out there concerning this issue. I would have NEVER bought a MB with a Sil controller on it if I had known that -- "Yea, you get GREAT throughput, WONDERFUL transfer rates ... but ... somewhere we kind of ... uhh .... sorta ... forgot to put interupt support in our drivers. So you can't USE your machine while your getting that great disk IO. Oh, and by the way, the drivers also chew up wads of memory. So you better have a gig or two laying around."

On a more serious note, and I realize this may be straying from the tech support forum, but can anyone recommend a PCI SATA raid card? I heard 3ware were good but I would like to hear "first hand" because I have never touched one before. I know Adaptec's are good, expensive, but good -- actually that was their SCSI cards. Their SATA raid cards could be sh*t. I understand I will be limited to the 133MB/sec transfer limit of the PCI bus ... but:

A - the drives I have can't exceed that right now anyway
B - I want a solution that allows the machine to remain usable even under very heavy disk IO. I know it is out there if 5 year old technology can do it...

Once the PCI Express chipsets mature for AMD I will be hoping on that bandwagon ... and Hypertransport will make all this a moot point. In the mean time ... I am sure there are others out there that have systems that are slower than what they COULD be and don't even know it because of a piss poor choice by Asus (and most nforce2 MB manufacturers) to use the POS Sil controller for their raid chip. Highpoint is not much better I understand.....

Someone, ANYONE, tell me there is hope -- I am not quite ready to go Athlon 64 yet.

 

[imported_Phil]

Interestingly enough, it's not "ALWAYS" faster. Sure, there's not a huge difference, but the conclusion is quite clear on this matter:

http://www.anandtech.com/storage/showdoc.aspx?i=2101&p=7
http://www.anandtech.com/storage/showdoc.aspx?i=2101&p=10

By the by, I would say that your problem is more likely to be CPU-bound, as the older platform will have a weaker CPU than your 3200+. Thus, QuickPAR is able to rag the drives as much as it likes because the processor isn't slowing things down.

This equals an increase in I/O throughput for the drives to handle, and (possibly) equals your slowdown.

Just an idea.

 

[mechBgon]

Powerstrip is NOT adware.

Then how come the antispyware apps--- well never mind, sounds like you made your mind up already

 

[rbV5]

Originally posted by: mechBgon

Powerstrip is NOT adware.

Then how come the antispyware apps--- well never mind, sounds like you made your mind up already

You guys are talking about 2 different things I believe.

PowerStrip

PowerStrip

are not the same thing. (Yikes)

PowerStrip is an awesome hardware utility from Entech , and apparently now " PowerStrip silently sets the afffiliate ID, so as to steal commission fees from your web shopping" <from the link> an exploit?

 

[runningnak3d]

By the by, I would say that your problem is more likely to be CPU-bound, as the older platform will have a weaker CPU than your 3200+. Thus, QuickPAR is able to rag the drives as much as it likes because the processor isn't slowing things down.

Whoa ... very good point. You are absolutely right even running one instance of QuickPAR on that old Duron pretty much does the CPU in. I guess bottom line then is that I would definitely like some recomendations on some SATA raid cards that have onboard processors or cache ram or WHATEVER it takes to drop in this machine and have nice disk throughput but remain usable. I have upped the ram to 2 gigs and that still hasn't solved the problem. I haven't gone out and actually read the SATA spec, but I am guessing that when they came up with it they envisioned people being able to multi-task even with massive disk IO. If I was hitting 100% cpu utilization this would be a non issue. But I only barely bump 10-20% ... that just isn't right.

Right now my "solution" to this issue is an old Dell 2450 server laying in the corner that I access with terminal services to do all my heavy disk work. The problem is, it has the same issue as the KT7 / Duron macihine ... it only has two 733Mhz PIIIs in it. So it runs out of steam LONG before the disk subsytem becomes an issue. It is LOUD though ... I hadn't turned it on in a few years and I had forgotten how loud that thing was ;-).

 

[runningnak3d]

rbV5:

Thanks for the heads up on the spyware by the same name.

mechBgone:

Sorry I doubted you dude.

 

[imported_Phil]

Originally posted by: runningnak3d

By the by, I would say that your problem is more likely to be CPU-bound, as the older platform will have a weaker CPU than your 3200+. Thus, QuickPAR is able to rag the drives as much as it likes because the processor isn't slowing things down.

Whoa ... very good point. You are absolutely right even running one instance of QuickPAR on that old Duron pretty much does the CPU in. I guess bottom line then is that I would definitely like some recomendations on some SATA raid cards that have onboard processors or cache ram or WHATEVER it takes to drop in this machine and have nice disk throughput but remain usable. I have upped the ram to 2 gigs and that still hasn't solved the problem. I haven't gone out and actually read the SATA spec, but I am guessing that when they came up with it they envisioned people being able to multi-task even with massive disk IO. If I was hitting 100% cpu utilization this would be a non issue. But I only barely bump 10-20% ... that just isn't right.

Right now my "solution" to this issue is an old Dell 2450 server laying in the corner that I access with terminal services to do all my heavy disk work. The problem is, it has the same issue as the KT7 / Duron macihine ... it only has two 733Mhz PIIIs in it. So it runs out of steam LONG before the disk subsytem becomes an issue. It is LOUD though ... I hadn't turned it on in a few years and I had forgotten how loud that thing was ;-).

Hmm. Personally, I don't think you're going to get the kind of disk I/O performance you're after unless you look at 10krpm+ SCSI RAID, with a few drives. 15krpm would be even better, to get the seek times down as much as possible.

I know that running more than one copy of QuickPAR on my machine (2600+ @ 2Ghz, 1Gb RAM, Seagate 200Gb 8Mb cache) slows things to a crawl, way way less than half the performance of one session because the disk is having to thrash so much.

I would think that the only real way around that would be to get the seek times down- this is going to cost you a fair bit, though.
Some nice Seagate Cheetah drives will be pricey, as will the controller card (LSI MegaRAID 320-1 should be okay, it's about £200 from our supplier here in the UK, IIRC).

You could get away with using, say, four or five 36Gb (maybe 74Gb) Fujitsu MAP 10krpm drives, they're nice and fast (although not as fast as those blistering Cheetah 15.3krpm drives), and I think they're on the "affordable" side.

Lastly, RAID-10 might work better for you, and also means that you don't need an all-powerful RAID card to make the array. We had a server a year or so ago (that I'm not allowed to talk about - NDA legal stuff), but I can say that it had 12 x 200Gb drives in RAID-10, and was pretty damned fast. I think they were SATA drives, I don't know if anyone makes a 12-port PATA RAID card.

Hope this helps